pcb
Home > Blog

Archive for the ‘Design Guide’ Category

High Frequency PCB Communication Circuits
Friday, October 4th, 2024

Best is mainly engaged in the production of High frequency pcb communication circuits, high-speed, microwave and radio frequency printed circuit boards, mainly in sample making and small and medium batches. The main products are: microwave radio frequency high-frequency boards, Rogers high-frequency boards, Rogers multi-layer high-frequency mixed-pressure boards, Rogers radio frequency boards, Taconic microwave boards, Taconic multi-layer circuit boards, Arlon microstrip antenna boards, ARLON high-frequency boards, F4BM antenna boards, F4BM multi-layer mixed-pressure boards, radio frequency amplifier PCB boards, HDI precision multi-layer boards, serving domestic and foreign high-tech enterprises and scientific research institutions.

‌What is a high frequency pcb communication circuits

High frequency pcb communication circuits to a circuit board with an operating frequency in the high frequency band (usually greater than 300MHz or a wavelength less than 1 meter), which is mainly used to transmit high-frequency signals and data. ‌ This type of circuit board is widely used in radio frequency (RF) and microwave fields, such as communication equipment, radar systems, satellite communications, and high-speed data transmission systems.

high frequency pcb communication circuits

What is a high frequency pcb communication circuits

The characteristics of high-frequency circuits include challenges such as transmission line effects, signal integrity issues, and electromagnetic interference (EMI). Due to the short wavelength of high-frequency signals, traditional low-frequency circuit design methods are no longer applicable, and special design and processing methods are required to ensure the performance and stability of the circuit.

High-frequency circuit boards are produced on microwave substrate copper-clad boards using ordinary rigid circuit board manufacturing methods or special processing methods. They need to have high-quality electrical properties and chemical stability to meet the requirements of high-frequency signal transmission.

Definition of high frequency pcb communication circuits

High-frequency circuit board, as a special circuit board, is mainly suitable for occasions with high electromagnetic frequency, especially in the fields of high frequency (frequency greater than 300MHz or wavelength less than 1 meter) and microwave (frequency greater than 3GHz or wavelength less than 0.1 meter).

It is a circuit board made on a microwave substrate copper-clad board by adopting some manufacturing processes or special processing methods of ordinary rigid circuit boards. Generally speaking, when the frequency of the circuit board reaches above 1GHz, it can be defined as a high-frequency board.

With the rapid development of science and technology, more and more equipment designs have begun to involve microwave frequency bands (>1GHz) and even expanded to the millimeter wave field (such as 77GHz), especially in popular applications such as 77GHz millimeter wave antennas on vehicles.

This trend not only promotes the continuous increase in frequency, but also puts higher requirements on the substrate of the circuit board.

For example, the substrate material needs to have excellent electrical properties, stable chemical properties, and as the frequency of the power signal increases, the loss on the substrate must be extremely small. Therefore, the importance of high-frequency boards is becoming more and more prominent.

Advantages of high frequency pcb communication circuits

The main advantages of high frequency pcb communication circuits include efficient data transmission, strong anti-interference ability, high-frequency bandwidth and high reliability. ‌

  1. high frequency pcb communication circuits can achieve efficient data transmission. High-frequency signals have a short cycle and can transmit more information per unit time, so they have the advantage of large-capacity transmission. In addition, high-frequency signals can achieve fast signal processing and are suitable for application scenarios that require high-speed data transmission and high real-time requirements.
  2. high frequency pcb communication circuits have strong anti-interference capabilities. Due to the short wavelength of high-frequency signals, they can better avoid external interference and attenuation and have strong anti-interference capabilities. This makes high-frequency signals have advantages in fields such as wireless communications and radar systems, and can achieve stable signal transmission and reception. ‌
  3. high frequency pcb communication circuits also have the advantage of high-frequency bandwidth. High-frequency signals correspond to a larger frequency range and can provide higher bandwidth than low-frequency signals. This means that more data can be transmitted, thereby supporting higher data rates and richer media content. ‌
  4. High reliability of high frequency pcb communication circuits is also one of its advantages. The use of high-quality materials and manufacturing processes can effectively resist external interference and oxidation corrosion, ensure stable performance in high temperature environments, and thus extend the service life of the circuit board.

Classification of high frequency pcb communication circuits

Classification by material:

  1. Organic materials: including phenolic resin, glass fiber/epoxy resin, Polyimide, BT/Epoxy (bismaleimide triazine/epoxy resin), etc.
  2. Inorganic materials: mainly including aluminum, copper-invar-copper, ceramic, etc. These materials are mainly selected for their excellent heat dissipation function.

Classification by the hardness of the finished product:

  1. Rigid PCB: has a solid structure and stable performance.
  2. Flexible PCB: has flexibility and bendability, suitable for occasions requiring flexible wiring.
  3. Rigid-Flex PCB: It combines the characteristics of rigid and flexible boards, and has higher design flexibility and wide application.

Classification by structure:

  1. Single-sided board: A circuit board with a conductive layer on only one side.
  2. Double-sided board: Both sides are coated with conductive layers, separated by insulating materials in the middle.
  3. Multilayer board: It is composed of multiple conductive layers and insulating layers, and has higher circuit integration and reliability.

Classification by use:

  1. Communication board: It is used in various communication equipment and systems.
  2. Consumable electronic board: It is commonly found in consumer electronic products.
  3. Military board: A circuit board that meets special requirements in the military field.
  4. Computer board: A circuit board used in computer hardware.
  5. Semiconductor board: A circuit board used in the manufacturing and testing process of semiconductors.
  6. Electrical test board: A circuit board used in electronic testing and measurement equipment.

How to choose high-frequency circuit board high-speed board

When choosing PCB board, you must find a balance between meeting design requirements, mass production and cost. In short, the design requirements cover two aspects: electrical performance and structural reliability. Especially when designing ultra-high-speed PCB (frequency greater than GHz), the choice of board is particularly important. For example, the commonly used FR-4 material will have a significantly increased dielectric loss (Df, i.e., Dielectric Loss) at a frequency of several GHz, and may no longer be applicable.

Taking the 10Gb/S high-speed digital signal as an example, this signal can be regarded as the superposition of multiple sinusoidal wave signals of different frequencies. Therefore, the 10Gb/S signal contains multiple components of different frequencies: such as a 5GHz fundamental signal, a 3rd-order 15GHz signal, a 5th-order 25GHz signal, and a 7th-order 35GHz signal. In order to ensure the integrity of digital signals, maintain the steepness of the upper and lower edges of the signals, and be compatible with the low-loss, low-distortion transmission of RF microwaves (the high-frequency harmonic part of the digital signal reaches the microwave frequency band), the selection of materials for high-speed digital circuit PCBs has many similarities with the needs of RF microwave circuits.

In actual engineering operations, the selection of high-frequency boards seems simple, but the factors that need to be considered are quite complex. Through the introduction of this article, PCB design engineers or high-speed project leaders can have a deeper understanding of the characteristics and selection of boards. Understand the electrical properties, thermal properties, reliability and other characteristics of the board, and use the stacking design reasonably to create products with high reliability and excellent processability, and achieve the best balance of various factors.

Composition and key components of high frequency pcb communication circuits

High frequency pcb communication circuits are basically composed of passive components, active devices and passive networks. Passive components include resistors, capacitors and inductors, which mainly exhibit resistance characteristics at low frequencies, but also exhibit reactance characteristics at high frequencies. Active devices such as high-frequency triodes have the characteristics of high gain, high frequency response and low noise, and are widely used in television, radio communication, radar and other fields.

Application of high frequency pcb communication circuits

High frequency pcb communication circuits are widely used in long-distance communication systems, with a communication distance of up to thousands of kilometers, and are often used to maintain communication between aircraft and bases. It occupies a high-frequency band of 2~30MHz, uses skywave propagation, and can propagate over long distances. Modern airborne high-frequency communication systems usually use single-sideband communication systems, which can greatly compress the occupied frequency band and save transmission power. However, high-frequency communication is also susceptible to electrical interference such as ionospheric disturbances and lightning, generating radio background noise, and there is fading, and the signal is sometimes strong and sometimes weak.

Design Guidelines for High Frequency PCB Communication Circuits

Design Guidelines

High Frequency PCB Communication Circuits

  1. How to avoid high-frequency interference?

The basic idea of ​​avoiding high-frequency interference is to minimize the interference of the electromagnetic field of high-frequency signals, which is the so-called crosstalk. You can increase the distance between high-speed signals and analog signals, or add ground guard/shunt traces next to analog signals. Also pay attention to the noise interference of digital ground to analog ground.

  1. How to solve the signal integrity problem in high-frequency communication PCB design?

Signal integrity is basically an impedance matching problem. The factors that affect impedance matching include the architecture and output impedance of the signal source, the characteristic impedance of the trace, the characteristics of the load end, and the topology of the trace. The solution is to rely on termination and adjust the topology of the trace.

  1. How is the differential wiring method implemented?

There are two points to note when wiring differential pairs. One is that the length of the two lines should be as equal as possible, and the other is that the spacing between the two lines (this spacing is determined by the differential impedance) should remain unchanged, that is, they should be kept parallel. There are two parallel methods, one is that two lines run on the same routing layer (side-by-side), and the other is that two lines run on two adjacent layers (over-under). Generally, the former side-by-side (side by side, shoulder to shoulder) is more commonly used.

  1. How to implement differential routing for clock signal lines with only one output end?

To use differential routing, it must be meaningful if both the signal source and the receiving end are differential signals. Therefore, differential routing cannot be used for clock signals with only one output end.

  1. Can a matching resistor be added between the differential line pairs at the receiving end?

The matching resistor between the differential line pairs at the receiving end is usually added, and its value should be equal to the value of the differential impedance. This will improve the signal quality.

  1. Why should the routing of differential pairs be close and parallel?

The routing method of differential pairs should be appropriately close and parallel. The so-called appropriate proximity is because this spacing will affect the value of differential impedance, which is an important parameter for designing differential pairs. Parallelism is also required because the consistency of differential impedance must be maintained. If the two lines are sometimes far away and sometimes close, the differential impedance will be inconsistent, which will affect the signal integrity and timing delay.

  1. How to deal with some theoretical conflicts in actual wiring?

Basically, it is right to separate the analog/digital ground. It should be noted that the signal routing should try not to cross the split place (moat), and the return current path of the power supply and signal should not be too large.

The crystal oscillator is an analog positive feedback oscillation circuit. To have a stable oscillation signal, the loop gain and phase specifications must be met. The oscillation specification of this analog signal is easily interfered. Even if ground guard traces are added, it may not be possible to completely isolate the interference. Moreover, if it is too far away, the noise on the ground plane will also affect the positive feedback oscillation circuit. Therefore, the distance between the crystal oscillator and the chip must be as close as possible.

It is true that there are many conflicts between high-speed wiring and EMI requirements. But the basic principle is that the resistors, capacitors or ferrite beads added due to EMI cannot cause some electrical characteristics of the signal to not meet the specifications. Therefore, first use the techniques of arranging routing and PCB stacking to solve or reduce EMI problems, such as routing high-speed signals on the inner layer. Only then use resistors, capacitors or ferrite beads to reduce damage to the signal.

  1. How to solve the contradiction between manual routing and automatic routing of high-speed signals?

Most of the current powerful routing software’s automatic routing tools have set constraints to control the winding method and the number of vias. The winding engine capabilities and constraint setting items of various EDA companies are sometimes very different. For example, whether there are enough constraints to control the winding method of the serpentine, whether the routing spacing of the differential pair can be controlled, etc. This will affect whether the routing method generated by automatic routing can meet the designer’s ideas. In addition, the difficulty of manually adjusting the routing is also related to the ability of the winding engine. For example, the pushing ability of the routing, the pushing ability of the via, and even the pushing ability of the routing to the copper plating, etc. Therefore, choosing a routing tool with a strong winding engine capability is the solution.

  1. About test coupon.

The test coupon is used to measure the characteristic impedance of the produced PCB board with TDR (Time Domain Reflectometer) to see if it meets the design requirements. Generally, the impedance to be controlled is single line and differential pair. Therefore, the trace width and line spacing (when there is a differential pair) on the test coupon should be the same as the line to be controlled. The location of the ground point during measurement is important. In order to reduce the inductance of the ground lead, the grounding point of the TDR probe is usually very close to the probe tip, so the distance and method between the point where the signal is measured on the test coupon and the ground point should be consistent with the probe used.

  1. In high-speed PCB design, the blank area of ​​the signal layer can be copper-plated, and how should the copper of multiple signal layers be distributed in grounding and power supply?

Generally, the copper plating in the blank area is mostly grounded. However, when plating copper next to high-speed signal lines, pay attention to the distance between the copper plating and the signal line, because the copper plating will reduce the characteristic impedance of the trace a little. Also be careful not to affect the characteristic impedance of other layers, such as in the dual strip line structure.

  1. Can the signal line on the power plane be calculated using the microstrip line model? Can the signal between the power and ground planes be calculated using the stripline model?

Yes, both the power plane and the ground plane must be considered as reference planes when calculating the characteristic impedance. For example, a four-layer board: top layer-power layer-ground layer-bottom layer. At this time, the model of the characteristic impedance of the top layer routing is a microstrip line model with the power plane as the reference plane.

  1. Can the automatic generation of test points on high-density printed circuit boards by software generally meet the test requirements of mass production?

Whether the test points automatically generated by general software meet the test requirements depends on whether the specifications for adding test points meet the requirements of the test equipment. In addition, if the routing is too dense and the specifications for adding test points are strict, it may not be possible to automatically add test points to each line. Of course, the places to be tested need to be filled manually.

  1. Will adding test points affect the quality of high-speed signals?

As for whether it will affect the signal quality, it depends on the way of adding test points and how fast the signal is. Basically, the additional test point (without using the existing via or DIP pin as the test point) may be added to the line or a short line may be pulled out from the line. The former is equivalent to adding a very small capacitor to the line, and the latter is an additional branch. Both situations will have some impact on the high-speed signal, and the degree of impact is related to the frequency speed of the signal and the edge rate of the signal. The magnitude of the impact can be known through simulation. In principle, the smaller the test point, the better (of course, it must meet the requirements of the test equipment) and the shorter the branch, the better.

  1. How should the ground wires between the boards of a system be connected when several PCBs are connected to each other?

When the signals or power supplies between the PCB boards are in operation, for example, when the power supply or signal from board A is sent to board B, there will be an equal amount of current flowing back from the ground layer to board A (this is Kirchoff current law). The current on the ground layer will flow back to the impedance. Therefore, at each interface where the power supply or signal is connected to each other, the number of pins allocated to the ground layer should not be too small to reduce the impedance, so as to reduce the noise on the ground layer. In addition, the entire current loop can be analyzed, especially the part with larger current, and the connection method of the ground layer or ground wire can be adjusted to control the flow of current (for example, create low impedance at a certain place to let most of the current flow through this place) to reduce the impact on other more sensitive signals.

You may also like

PCB Quote Packaging is What Type of Engineering?
Tuesday, September 10th, 2024

PCB Full Form

PCB stands for Printed Circuit Board, a key component in almost all electronic devices. It connects and supports electronic components using conductive tracks, pads, and other features. The design and production of PCBs require precise engineering, as they are crucial for the functionality of the final product.

What is PCB Quote Packaging?

PCB quote packaging refers to the process of gathering and organizing all the details needed to estimate the cost of producing a PCB. This includes not only the design specifications but also the materials, manufacturing processes, and other engineering considerations. It’s not just a financial calculation but a complete engineering analysis that ensures the quote is accurate, feasible, and optimized for production.

The quote must consider every detail that affects production—like material types, size, complexity, and production volume. The aim is to package all these details into a clear, comprehensive quote, ensuring the client understands what they are paying for and why.

Why is Engineering Important in PCB Quote Packaging?

Engineering plays a vital role in the PCB quoting process because it’s not just about estimating costs. It’s about understanding the technical requirements and ensuring that every aspect of the design and production is accounted for. Engineers analyze the design, materials, and manufacturing methods to ensure the quote reflects the real cost of production.

Without engineering insight, a quote could be inaccurate, leading to cost overruns or production delays. Engineers make sure that all technical details, such as layer count, trace width, and component placement, are properly considered.

What Are the Key Factors in a PCB Quote?

Several factors come into play when preparing a PCB quote:

PCB Quote Packaging is What Type of Engineering?

1. Type of manufacturing process

The technical type of PCB determines its complexity and cost. For example, simple single panels cost much less than multi-layer panels, while flexible circuits (FPC) or rigid and flexible panels require more complex manufacturing processes and naturally cost more. In addition, whether advanced technologies such as microvias, laser drilling, blind holes or buried holes are required can also have a significant impact on the quotation.

2. Material type

Materials are an important part of PCB costs. Common materials include FR4, ceramics, metal substrates, etc. FR4 is the most common base material and is suitable for most conventional applications, but for high-frequency, high-temperature environments, ceramic or metal-based materials may be more suitable, but their price is relatively high. Choosing the right material not only affects the performance, but also directly affects the cost.

3. IPC level

IPC grades reflect the quality standards of PCB manufacturing, commonly used are IPC-A-600 grades 1, 2 and 3. The higher the grade, the more stringent the manufacturing requirements, and the corresponding increase in cost. For example, grade 3 PCBS are usually used in high-demand fields such as aerospace and medical equipment, which require higher accuracy and quality control, so the price is higher.

4. Circuit design

PCB circuit design complexity directly affects manufacturing costs. Including wire width, spacing, hole size and so on, the production process has put forward different requirements. High density interconnect (HDI) boards typically require more elaborate wiring techniques and may involve the use of microvias, which will increase the difficulty and cost of manufacturing.

5. PCB size and yield

The size of the PCB directly affects the amount of material used, and the larger the board, the more material is needed. In addition, the yield is also an important factor affecting the quotation. PCB manufacturing with complex design or high density lines is prone to defects, resulting in decreased yield. That means manufacturers may need to produce more boards to meet orders, increasing costs.

6. Material thickness

Different applications require different thicknesses of PCB materials. The standard FR4 thickness is usually 1.6mm, but thinner or thicker boards are sometimes used. Changes in material thickness can affect the overall cost, especially if thicker sheets require special processing or higher strength, and manufacturing expenses will increase accordingly.

7. Copper thickness

The copper thickness in the PCB usually has a standard choice, such as 1oz, 2oz or even thicker copper layers. The higher the copper thickness, the better the conductivity of the PCB, suitable for high-current applications, but the increase in copper thickness will significantly increase the manufacturing cost, especially in the plating and etching process requires additional materials and processes.

8. Stack-up method

The stacking mode determines the number of layers and the interlayer structure of the PCB. Complex multilayer boards or HDI boards require more complex lamination processes. For example, the lamination method may involve multiple pressing, the use of prepregs or special insulation materials. Each additional layer requires more manufacturing steps, resulting in increased costs.

9. Quantity

The quantity of the order has a direct impact on the PCB quotation. High-volume production can reduce unit prices by spreading tooling and setup costs, while small-batch orders are typically more expensive due to relatively high production preparation and start-up costs.

10. Delivery date

The shorter the delivery time, the higher the quotation. Rush orders require prioritizing production, which can disrupt the plant’s production schedule and require additional resource deployment. To meet urgent delivery deadlines, manufacturers may need to work overtime or speed up production, increasing overall production costs.

These are just a few examples, but they show how engineering considerations are woven into every part of the quoting process.

PCB Manufacturing Process

How Do Engineers Calculate PCB Manufacturing Costs?

Engineers calculate PCB manufacturing costs by considering the design specifications and the production methods needed to meet those requirements. They start by analyzing the PCB’s layout and design, which determines factors like layer count, trace width, and hole size. Each of these elements has a direct impact on the materials used and the manufacturing process.

They also consider the assembly process—whether it’s surface-mount or through-hole—and what testing will be required. After evaluating these details, they calculate the costs associated with each step of the manufacturing process. This ensures the final quote is both accurate and comprehensive.

What Type of Engineer Designs PCBs?

Engineers who design PCBs typically have a bachelor’s degree or above in electrical engineering, automation, computer science, or a related field ‌ and understand the basics of electronic design, printed circuit board (PCB), and electronics manufacturing in the PCB industry. These engineers need to master PCB design software such as Altium Designer, Eagle PCB, PADS, or CAD, etc., as well as the use of related manufacturing and testing tools. At the same time, they need to have a knowledge of the PCB industry, a certain circuit design and electronic components knowledge, including digital and analog circuits, signal processing, power electronics, embedded systems, communication technology, etc. In addition, holding certificates such as IPC-2221/2222, IPC-A-600/610, and CID (Certified Interconnect Designer) can prove that they have relevant professional knowledge and skills, which can help improve their career competitiveness.

These engineers also need to have a strong sense of responsibility and team spirit, have good communication and coordination skills, and be able to work effectively with customers, manufacturers, and other team members. For junior engineers, it is recommended to study in a single point of depth, such as PCB design, SI simulation, thermal design, EMC design, product testing, etc., and then start from this advantage point to expand the scope of knowledge

What Materials Are Considered During PCB Quote Packaging?

The type of material used for a PCB is a major cost driver. Common materials include:

  • FR4

This is the most common material used in PCBs due to its balance of cost and performance. It’s versatile and reliable for most standard applications.

PCB Quote Packaging is What Type of Engineering?
  • Metal Core

Metal core PCBs are used in applications where heat dissipation is a concern, such as LED lighting. These boards are more expensive due to the metal layer.

PCB Quote Packaging is What Type of Engineering?
  • Ceramic

Ceramic materials are used for high-frequency or high-temperature applications. They are more costly but offer better performance in extreme conditions.

PCB Quote Packaging is What Type of Engineering?

Each material has its own manufacturing process, which also affects the cost. For instance, metal core boards may require different drilling techniques compared to standard FR4 boards. Engineers must consider these details when preparing a quote.

How Does the Choice of PCB Manufacturing Methods Impact the Quote?

The method used to manufacture the PCB can greatly impact the final cost. Common methods include:

  • Surface-Mount Technology (SMT): This is the most common method for modern PCB assembly. It’s efficient and cost-effective for most applications.
  • Through-Hole Technology (THT): This method is used for components that require a stronger mechanical bond. It’s more labor-intensive and, therefore, more expensive.
  • Flexible and Rigid-Flex Manufacturing: These types of PCBs require specialized processes and materials, which can increase the cost.

Additionally, advanced techniques like laser drilling for microvias or selective soldering for complex assemblies may be necessary for high-precision designs. Each of these methods requires careful consideration, and engineers must choose the best process for both the design and the budget.

Who Designs PCB?

Since 2006, Best Technology has been the leading PCB quick turn manufacturer specializing in both PCB prototype and production quantities, initially produced single-sided and double-sided printed circuit boards for the consumer electronics market. Now, we provide not only FR4 PCB, but also some special PCB like flex circuit, metal core PCB, ceramic PCB, extra thin PCB, HDI PCB, IC substrate, busbar PCB, heavy copper PCB and so on. We can make 50 layers PCB, and it is not our limit.

Nowadays, Best Technology has grown to become a major PCB manufacturer in Asia to serve in diverse customers base such as electronics appliance, communication, educational electronics, power supplies, automations.

For more information about PCB, or to learn more about the online quote and ordering process, please visit www.bestpcbs.com

You may also like

PCB Stack-up and Impedance Control Guidelines
Friday, August 23rd, 2024

When designing a PCB board, careful attention to stack-up and impedance control is essential for achieving optimal signal integrity and performance. The PCB stack-up refers to the arrangement of copper and insulating layers that make up the board. Impedance control, on the other hand, involves maintaining consistent electrical characteristics within signal traces, especially in high-speed circuits. This post provide a detailed guideline of PCB stack-up and impedance control for designers.

PCB Stack-up Parameter

Internal Copper Thickness After Processing

Base FoilMin. After Processing
18um (1/2oz)11.4um
35um (1oz)24.9um
70um (2oz)55.7um
105um (3oz)86.6um
140um (4oz)117.5um

External Copper Thickness After Plating

Base FoilMin. Class 2Min. Class 3
12um (3/8oz)29.3um34.3um
18um (1/2oz)33.4um38.4um
35um (1oz)47.9um52.9um
70um (2oz)78.7um83.7um
105um (3oz)108.6um113.6um
140um (4oz)139.5um144.5um

Common Prepreg (PP) Properties

TypeThickness (mm)Resin (%)
1060.0565
10800.07565
21160.1255
76280.246

Common Material List

Medium TgShengyi S1000-H
ITEQ IT-158
Elite EMC-825
High TgShengyi S1000-2M
ITEQ IT-180A
Elite EMS-827

Common Core Thickness

PCB Stack-up and Impedance Control Guidelines

Design Tips – Stack-up

1. Ensure the stack-up remains symmetric.

2. Typically, a foil build is recommended. Special core builds, like those with Rogers, are possible but less common.

3. For boards thicker than 1mm, the standard thickness tolerance is +/-10%. For 1mm boards, the standard tolerance is +/-0.1mm. Any board with a thickness ≤1mm requires approval from Best Tech.

4. The minimum dielectric thickness will be 90µm, according to IPC standards, unless otherwise specified by the FAB drawing and there are no micro vias.

5. Use a maximum of three sheets of prepreg to bond the layers.

6. While the stack-up used in production may differ slightly from the specified one, an Engineering Query (EQ) will be sent for confirmation.

7. Variations can occur due to factors like copper distribution and available materials.

8. Thicker copper foils require thicker dielectrics between layers, and the foil thickness after processing differs from the base foil thickness.

9. Additionally, variations in resin percentage for the same prepreg type can impact the final prepreg thickness.

10. When incorporating micro vias, consider the aspect ratio—recommended at 0.8:1 and advanced at 1:1—when selecting prepreg.

If you need special materials, thickness tolerances, or stack-ups, contact Best Technology for guidance. Below are some suggested stack-ups for different layers PCB.

PCB Stack-up and Impedance Control Guidelines
PCB Stack-up and Impedance Control Guidelines

Impedance Parameters Needed for Calculation

PCB Stack-up and Impedance Control Guidelines
SymbolFeature
H1, H2, H3..Dielectric thickness between copper layers after pressing
Er1Dielectric constant of prepreg or core used between copper layers.
W1The bottom width od impedance lines, which is the customer required impedance trace width.
W2The top width of impedance lines.
S1The space between two differential impedance traces.
T1Finished copper thickness, which is different with our normal definition.
C1Solder mask thickness on material.
C2Solder mask thickness on copper.
C3Solder mask thickness on material between traces (C1 = C3).
CErDielectric constant of solder mask. Normally use 3.4 to calculate.

Tolerance of Impedance Control

Type of ImpedanceCommon Requested ValueTolerance of Impedance Control
GeneralModerateAdvanced
Single/Single Coplanar        40Ω/510Ω/75Ω+/-10%+/-8%+/-5%
Differential/Differential Coplanar90Ω/100Ω/120Ω+/-10%+/-8%+/-5%

Relationship between Parameters and Impedance Value

Parameters ModificationEffect on Impedance Value
ParametersIncrease/ReduceImpacts on impedanceImpedance value increase/reduced
H (dielectric thickness)IncreaseBigIncrease
W (trace width)IncreaseBigReduced
S (trace space)IncreaseBigIncrease
T (copper thickness)IncreaseLowReduced
C (solder mask thickness)IncreaseLowReduced

Design tips – Impedance

When signal speeds exceed 2 GHz and timing is critical, consider using better materials such as medium, high, or ultra-high-speed options, along with flat glass styles. To ensure a reliable lamination process and prevent resin starvation, allow the factory to select the number of prepregs, prepreg styles, and resin content in the stack-up.

Key factors influencing impedance signal losses include:

1. Line Length: Signal losses are directly proportional to the line length—shorter lines result in fewer losses, while longer lines lead to greater losses.

2. Dielectric Loss: These losses can be minimized by selecting appropriate materials.

3. Copper Loss: This includes losses from the cross-sectional area (affected by stack-up design) and surface roughness, which can be reduced through material selection and proper stack-up configuration.

If you require impedance tolerances tighter than +/-10%, discuss your design possibilities with the Best Technology team.

When designing rigid-flex boards, note that separate calculations are necessary for both the rigid and flex sections of the same signal. Manufacturers will adjust the thickness and dielectric constant of the solder mask based on their solder mask properties and printing method. Variations in resin content for the same prepreg type can also affect impedance. For assistance with impedance calculations, contact Best Technology for support.

PCB Stack-up and Impedance Control Guidelines

Checklist of Necessary Information for Impedance Calculations

1. Specify the type, value, and tolerance of impedance control.

2. Ensure you define the width and space of impedance traces, as well as the layers where these traces will be present, along with the layers to be considered as reference points.

3. Identify the type of material and final board thickness, and provide a reference stack-up for the design.

4. Confirm the finished copper thickness on external and internal layers, and note if any special type of solder mask is required.

5. Always request Best Technology’s stack-up before starting the routing design.

You may also like

Power Supply Circuit Design Guide – An Overview
Wednesday, August 21st, 2024

A power supply circuit is at the heart of every electronic device, transforming available energy into usable power. Whether you’re developing a new product or repairing an existing one, a firm grasp of power supply circuit design helps in improving efficiency, and performance. The main objective of this blog is to share know-how about power supply circuit, from the definition, types, power supply circuit board and more. Here we go!

Power Supply Circuit – An Overview

What Are the Three Types of Power Supply?

There are three subsets of regulated power supplies: linear, switched, and uninterruptible battery based. Of the three basic regulated power supply designs, linear is the least complicated system, but switched and battery power have their advantages.

Linear power supply

This is one of the simplest forms. It uses a transformer to reduce the input voltage to the desired level, then relies on a regulator to maintain stable voltage. Linear power supplies are known for their low noise output and reliability. However, they can be inefficient because they dissipate excess energy as heat.

Power Supply Circuit – An Overview

Switching power supply

This type is much more efficient than linear power supplies. It rapidly switches the power on and off to control the output voltage. By doing so, switching power supplies can achieve higher efficiencies, making them ideal for modern electronics where energy conservation is crucial. They are compact and offer better energy savings but can introduce noise into the circuit.

Power Supply Circuit – An Overview

Uninterruptible power supply (UPS)

A UPS provides emergency power when the main source fails. It’s widely used in environments where power interruptions could cause data loss or equipment damage, such as in data centers or hospitals. It combines elements of both linear and switching power supplies, offering reliability and backup in case of failure.

What Are the Problems with Power Supply Circuits?

Power supply circuits are not without challenges, but understanding these issues can help mitigate them.

  • Heat generation

Some power supplies, especially linear ones, generate significant heat during operation. This can affect the longevity of components and the overall performance of the device. Adding heat sinks or better cooling can help manage this issue.

  • Voltage fluctuations

Inconsistent power supply can lead to voltage drops or spikes. Sensitive electronics might malfunction or get damaged under such conditions. Proper filtering and regulation can address these fluctuations.

  • Electrical noise

Switch-mode power supplies are efficient but can introduce electrical noise into the circuit. This noise can interfere with the performance of other components, especially in sensitive applications. Careful circuit design, shielding, and grounding can reduce the impact.

Common Power Supply Circuit Diagram

A diagram representing circuit connections with circuit component symbols is called a circuit diagram. Circuit diagram is a kind of schematic layout diagram that represents the composition and relationship of components and devices drawn by the symbols of physical and electrical standardization for the needs of research and engineering planning, which can know the working principle of components and provide planning schemes for the analysis of performance and installation of electronic and electrical products.

Circuit diagram is one of the basic skills that electronic engineers must learn, here we listing four common power supply circuit diagrams, which is super full super detailed. Hope it is useful for you!

Regulated Power Supply Circuit Diagram

This type uses voltage regulators to maintain a constant output voltage regardless of input fluctuations. Let’s take an example of an 3~25V adjustable voltage regulator circuit. This regulated power supply can be adjusted within a range of 3.5V to 25V. It provides a large output current and uses an adjustable voltage regulator circuit. You can see its circuit diagram as below:

Power Supply Circuit – An Overview

Its working principle is: after rectification and filtering, the DC voltage is supplied to the base of the adjustment transistor through R1, which makes the transistor conduct. When V1 conducts, the voltage passes through RP and R2 to make V2 conduct, and then V3 also conducts. At this point, the emitter and collector voltages of V1, V2, and V3 no longer change (their function is completely similar to that of a zener diode). By adjusting RP, a stable output voltage can be obtained. The ratio of R1, RP, R2, and R3 determines the output voltage of this circuit.

Component Selection

Transformer T: Choose an 80W to 100W transformer, with an input of AC220V and a dual winding output of AC28V.

FU1: Use a 1A fuse.

FU2: Use a 3A to 5A fuse.

VD1, VD2: Use 6A02 diodes.

RP: Use an ordinary potentiometer rated at around 1W, with a resistance value between 250K and 330K.

C1: Use a 3300µF/35V electrolytic capacitor.

C2, C3: Use 0.1µF monolithic capacitors.

C4: Use a 470µF/35V electrolytic capacitor.

R1: Use a resistor with a value between 180Ω and 220Ω, rated at 0.1W to 1W.

R2, R4, R5: Use 10KΩ resistors, rated at 1/8W.

V1: Use a 2N3055 transistor.

V2: Use a 3DG180 or 2SC3953 transistor.

V3: Use a 3CG12 or 3CG80 transistor.

Switched-Mode Power Supply (SMPS) Circuit

This circuit is used in many modern electronics because of its high efficiency. It includes a switching regulator that controls the energy flow, converting the input voltage to the required output through rapid switching. Below is a power supply circuit diagram of a 12V, 20W SMPS system with TOP224P.

Power Supply Circuit – An Overview

From the above, VDz1 and VD1 clamp the spike voltage generated by leakage inductance to a safe level and attenuate ringing voltage. VDz1 uses a P6KE200 transient voltage suppressor with a reverse breakdown voltage of 200V, while VD1 is a UF4005 ultra-fast recovery diode rated at 1A/600V. The secondary winding voltage is rectified and filtered through VD1, C2, L1, and C3, producing a 12V output voltage (Uo). The value of Uo is determined by the sum of the stable voltage of VDz2, the forward voltage drop across the LED in the optocoupler, and the voltage drop across R1.

By adjusting the turns ratio of the high-frequency transformer and the stabilization value of VDz2, other output voltages can also be obtained. R2 and VDz2 provide a dummy load for the 12V output, improving load regulation during light load conditions. The feedback winding voltage is rectified and filtered by VD3 and C4 to supply the necessary bias to the TOP224P. Common mode choke L2 reduces common-mode leakage current caused by the high-voltage switching waveform on the primary winding’s D-terminal. C7 filters interference from the coupling capacitance between the primary and secondary windings, while C6 minimizes differential-mode leakage currents from the primary winding. Additionally, C5 filters peak current on the control terminal and, together with R1 and R3, compensates the control loop and determines the self-starting frequency.

Transformer-Based Power Supply Circuit

This is the most basic power supply circuit, often used in low-power applications. It involves a transformer to reduce the input AC voltage, followed by rectification and filtering to produce a steady DC output.

Battery-Powered Circuit

For portable devices, battery-powered circuits offer a reliable power source. These circuits are designed to manage the charging and discharging of batteries while providing stable power to the device.

Which kind of PCB used for power supply circuit?

1. Heavy copper PCB

Heavy copper PCBs are designed with significantly thicker copper layers compared to standard PCBs. Typically, they feature copper weights greater than 3 ounces per square foot. These PCBs excel in handling higher currents and distributing power across the circuit more effectively, making them ideal for power distribution systems, power converters, and other demanding applications. Bus bar PCBs are a subtype of heavy copper boards, specifically designed for applications requiring high current capacity and low impedance.

Heavy copper PCBs are used when standard copper traces cannot carry the required current without excessive heat buildup. By increasing the thickness of the copper layers, these PCBs can manage higher currents, dissipate heat better, and enhance the board’s durability. They are crucial in industries like automotive, solar power, and industrial control, where reliable power management is key.

2. Metal Core PCB

Metal core PCBs also call led pcb board, are built with a metal substrate, typically aluminum or copper, to efficiently dissipate heat generated by high-power circuits. These boards are widely used in LED lighting, power supplies, and automotive electronics where heat management is essential. For extra high power supply applications, copper core PCB is a good choice.

3. Ceramic PCB

Ceramic PCBs are highly favored in environments where high thermal conductivity and electrical insulation are needed. They can be used under -80C ~ 2200C. They perform well in high-frequency applications and can operate in harsh conditions, making them suitable for aerospace, military, and industrial power electronics.

How to Build a 12V Power Supply Circuit?

Building a 12V power supply circuit can be a rewarding project, whether you’re creating it for a specific device or learning about electronics. Below is a detailed guide to help you design and build a reliable 12V power supply.

Components Needed

Before you begin, gather the essential components:

  • Transformer: A step-down transformer will reduce the AC mains voltage (usually 110V or 220V) to a lower AC voltage that can be rectified and regulated to 12V DC. A common choice is a transformer that outputs 15V AC.
  • Bridge Rectifier: This consists of four diodes arranged to convert AC to DC. The diodes ensure that the output is always in the same polarity, transforming the alternating current into a pulsating direct current.
  • Capacitors: Capacitors act as filters to smooth out the pulsating DC output from the rectifier, reducing ripple and providing a more stable DC voltage.
  • 12V Voltage Regulator: A voltage regulator like the LM7812 ensures that the output remains at a steady 12V DC. This is crucial to prevent voltage fluctuations, which could damage sensitive electronic components.
  • Heat Sink: A heat sink is necessary to dissipate heat from the voltage regulator, especially when there’s a significant voltage drop between the input and the 12V output.
  • Fuse: To protect your circuit from overcurrent situations, a fuse should be added at the input or output stage.
  • Optional Components: You might include an LED indicator and resistor to show when the power supply is active.

Step-by-Step Process

Here’s how to assemble the components into a functional 12V power supply circuit:

Step 1: Connect the Transformer

The transformer’s primary winding is connected to the AC mains, reducing the input voltage to around 15V AC on the secondary winding. This step-down AC voltage will feed into the rectifier circuit.

Step 2: Bridge Rectifier Configuration

The output of the transformer is connected to the bridge rectifier. The rectifier converts the AC voltage into a pulsating DC voltage. The output voltage will still have ripples (fluctuations in the voltage level) and needs further smoothing.

Step 3: Filter the Output with Capacitors

A capacitor is connected across the output of the bridge rectifier to smooth the pulsating DC signal. This helps to reduce ripple and stabilize the voltage. A larger capacitor will give better smoothing, but a typical value used is around 1000µF. The capacitor works by charging up during the peaks of the rectified signal and releasing energy during the valleys, leading to a more stable DC voltage.

Step 4: Voltage Regulation

After the rectified and filtered voltage, you will likely have a DC voltage around 15V, which is still too high for a 12V power supply. This is where the 12V voltage regulator (e.g., LM7812) comes into play. The regulator ensures the output remains at a constant 12V, regardless of input variations or load changes.

1. Connect the input pin of the regulator to the positive output of the rectifier.

2. Connect the ground pin to the common ground.

3. The output pin will now deliver a regulated 12V DC.

Step 5: Add the Heat Sink

Voltage regulators can generate significant heat, especially when the difference between the input and output voltage is large. Attach a heat sink to the regulator to prevent overheating and ensure stable operation.

Step 6: Safety Measures

To protect the circuit from potential damage, include a fuse on the input side. This fuse will blow if there’s a short circuit or an overload, preventing the transformer or other components from getting damaged. For example, you can use a 1A fuse.

Step 7: Test the Circuit

Once the circuit is assembled, double-check all connections and test the output with a multimeter. Make sure the output voltage is stable at 12V under no load and when powering a device.

Optional: Add Features

You can add an LED indicator with a series resistor to the output side. This will visually indicate when the power supply is on and functioning.

Practical Considerations

Load Capacity: The transformer’s power rating (VA) should be sufficient to handle the current drawn by the load. For instance, if your load requires 1A at 12V, the transformer must be able to supply at least 12 watts (plus some margin to account for inefficiency and losses).

Heat Management: If your power supply will be operating under heavy load, consider adding active cooling, such as a small fan, especially if the heat sink alone does not adequately dissipate heat.

Enclosure: For safety and aesthetics, house the power supply in an insulated, vented enclosure to prevent accidental contact with live wires and to allow for heat dissipation.

A Simple Example

Once completed, this 12V power supply circuit can be used for a wide variety of applications:

Small Electronics Projects: Power up microcontrollers, sensors, or other small electronics that run on 12V.

LED Lighting: It can be used to power 12V LED strips or other lighting systems.

Arduino or Raspberry Pi Projects: Many DIY electronics projects require a steady 12V supply to operate correctly, and this circuit can deliver that power reliably.

You may also like

PCB Line Width and Flow Current Comparison Table
Monday, August 19th, 2024

PCB Line Width and Flow Current Comparison Table

In PCB manufacturing, the term of “OZ” always refers to copper thickness, 1OZ thickness means evenly spread 1OZ copper foil on the 1 square foot areas, and this thickness is around 0.035mm. So, 35um, 50um, 70um correspond to 1OZ, 1.5OZ, 2OZ.

The full name of OZ is ounce, it is the weight per unit area to express the thickness of the copper foil, the format is: 1OZ=28.35g/FT2

PCB Line Width and Flow Current Comparison Table Chart

PCB Line Width and Flow Current Comparison Table Chart
Line width (mm)Current (A)Line width (mm)Current (A)Line width (mm)Current (A)
0.150.20.150.50.150.7
0.20.550.20.70.20.9
0.30.80.31.10.31.3
0.41.10.11.350.41.7
0.51.350.51.70.52.0
0.61.60.61.90.62.3
0.82.00.82.40.82.8
1.02.31.02.61.03.2
1.22.71.23.01.23.6
1.53.21.53.51.54.2
2.04.02.04.32.05.1
2.54.52.55.12.56.0
Copper thickness 1OZ (0.035mm)Copper thickness 1.5OZ (0.05mm)Copper thickness 2OZ (0.7mm)

From the chart as above:

35um copper thickness and 0.4mm line width, the current is 1.1A;

50um copper thickness and 0.4mm line width, the current is 1.35A;

70um copper thickness and 0.4mm line width, the current is 1.7A.

Best Technology PCB Line Width and Flow Current Calculator

When using copper foil as a conductor for large currents, the width of the copper foil should be selected by reducing the current-carrying capacity values from the reference table by 50%. However, there are other methods to address this. In some power circuits, due to PCB constraints, the current-carrying paths are designed as long pads, and solder is added on top of them to form a thick current path. Besides adding tin to the copper foil to increase the current capacity, you can also consider using multiple PCB layers to increase the current. For instance, placing the same circuit on both the top and bottom layers or using short jumper wires can also help increase the current capacity.

How Wide Should the Trace be If Current is 1A?

1. Due to the limited thickness of the copper foil on the copper-clad board, the current-carrying capacity of the copper foil needs to be considered for strip-shaped copper foil that needs to carry a large current. Taking the typical thickness of 0.03mm as an example, if the copper foil is used as a strip-shaped conductor with a width of W (mm) and a length of L (mm), its resistance is 0.0005 L / W ohms. Additionally, the current-carrying capacity of the copper foil is related to the types of components installed on the PCB, their quantity, and the heat dissipation conditions. Under safe conditions, the current-carrying capacity can generally be calculated using the empirical formula: 0.15 W (A).

2. The calculation method is as follows: First, calculate the cross-sectional area of the track. Most PCBs have a copper foil thickness of 35μm (if unsure, you can ask the PCB manufacturer). Multiply this by the trace width to get the cross-sectional area, making sure to convert to square millimeters. There’s an empirical value for current density, which is 15-25 amperes per square millimeter. Multiply this by the cross-sectional area to get the current capacity.

3. I = K T^0.44 A^0.75, where K is a correction factor (0.024 for internal copper traces, 0.048 for external copper traces), T is the maximum temperature rise in degrees Celsius (copper’s melting point is 1060°C), A is the copper cross-sectional area in square mils (not square millimeters, so be mindful of the conversion), and I is the allowable maximum current in amperes (amps). Typically, 10 mil = 0.010 inches = 0.254 mm, which can carry 1A. Therefore, 250 mil = 6.35 mm can carry 8.3A.

4. The calculation of PCB current-carrying capacity has long lacked authoritative technical methods and formulas. Experienced CAD engineers can make accurate judgments based on personal experience. However, for CAD novices, this can be quite a challenge.

5. PCB current-carrying capacity depends on the following factors: trace width, trace thickness (copper foil thickness), and allowable temperature rise. As we all know, the wider the PCB trace, the greater the current-carrying capacity. Under the same conditions, a 10mil trace can carry 1A, but can a 50mil trace carry 5A? The answer is, of course, no.

Current-Carrying Capacity of External PCB Traces (1mil = 0.0254mm)

Line length  current carrying data chart (unit: A)
 
Line width (mil)Line length 5cmLine length 10cmLine length 15cmLine length 20cmLine length 25cmLine length 30cmLine length 35cmLine length 40cm
40.4030.201.0.1340.1010.0810.0670.0580.050
60.6040.3020.2010.1510.1210.1010.0860.075
80.7530.4030.2680.2010.1610.1340.1150.101
100.8860.5030.3360.2520.2010.1680.1440.126
121.0110.6040.4030.3020.2420.2010.1730.151
161.2450.8050.5370.4030.3220.2680.2300.201
201.4641.0070.6710.5030.4030.3360.2880.252
301.9641.5101.0070.7550.6040.5030.4310.378
402.4192.0131.3421.0070.8050.6710.5750.501
502.8442.5171.6781.2581.0070.8390.7190.629
603.2463.0202.0131.5101.2081.0070.8620.755
803.9993.9992.6842.0131.6111.3421.1501.007
1004.7014.7013.3562.5172.0131.6781.4381.258
1205.3655.3654.0273.0202.4132.0131.7261.510
1606.6106.6105.3694.0273.2212.6842.3012.013
2007.7707.7706.7115.0334.0273.3552.8762.517
2408.8688.8688.0536.0404.8324.0273.4513.020
2809.9179.9179.3957.0475.6374.6984.0273.523
32010.92510.92510.7388.0536.4435.3694.6024.027
36011.89911.89911.8999.0607.2486.0405.1774.530
40012.84412.84412.84410.0678.0536.7115.7525.033

For low-frequency, low-current PCB designs, the general trace width is around 10 mil, and for more compact designs, 6 mil may be used. The key factor in determining PCB trace width is the current: higher currents require wider traces, while lower currents can use narrower traces. The operating frequency also plays a role in determining the width.

  1. Ideally, the width of the PCB power trace should be at least 40 mil, with a minimum of 25 mil when conditions allow. Always opt for the widest trace possible to accommodate the current.
  2. Consider the actual current flow. Typically, a 10 mil trace can carry a maximum of 1A, so adjust the width according to the current requirements.
  3. The ground trace should be wider than the V+ trace and should surround the V+ trace to reduce interference and power ripple.
  4. When converted to millimeters, the positive power trace should be no less than 0.6mm wide, while the negative power trace should be wider than the positive trace and surround it.

How Are Multilayer Boards Constructed?

The multi-layer board is composed of several single sided PCB for the outer layer and some double-sided PCBs for the inner layer.

l Single-Sided Boards

In the most basic PCB design, components are placed on one side of the board, and the wiring is on the other. This is called a single-sided board. Due to strict routing limitations (since traces cannot cross each other), single-sided boards are mostly used in simpler circuits.

l Double-Sided Boards

Double-sided boards have wiring on both sides. To connect the circuits on both sides, vias (small holes filled or coated with metal) are used. The larger area and ability to route traces through both sides make double-sided boards more suitable for complex circuits compared to single-sided boards.

l Multilayer Boards

To increase routing space, multilayer boards are created by combining multiple layers of single-sided or double-sided boards. For example, a four-layer or six-layer PCB might consist of a double-sided board as the core with single-sided boards on either side, all bonded together. Multilayer boards allow more complex designs, and while most modern PCBs use between 4 to 8 layers, designs with up to 100 layers are possible for advanced computing needs, though they are increasingly rare due to advances in other technologies.

The number of layers doesn’t always indicate the number of wiring layers—some layers may be added purely to adjust board thickness. Most motherboard designs consist of 4 to 8 layers, and while extremely complex multilayer boards were once used in supercomputers, they are now often replaced by clusters of standard machines.

Trace Width and Copper Pour Guidelines

When designing PCBs, a general rule is to use thicker traces for high-current areas (e.g., 50 mil or more) and thinner traces for low-current signals (e.g., 10 mil). In some electromechanical control systems, the instantaneous current through a trace can exceed 100A, in which case thin traces would fail.

An empirical rule of thumb is that 10A can safely pass through 1 square millimeter of trace cross-section. If the trace is too thin, it may burn out under high current. This phenomenon follows the energy equation: Q = I^2*t. For example, a trace designed for 10A can likely handle a sudden current spike of 100A for microseconds, but beyond that, other factors like stray inductance in the trace could generate strong counter-electromotive forces, potentially damaging other components. Longer and thinner traces have higher stray inductance, so their length must also be considered.

Copper Pouring on Vias and Pads

Most PCB design software offers options for how to connect vias or pads to copper planes, such as direct pour, orthogonal spokes, or 45-degree angled spokes. While many designers select based on aesthetics, these choices affect both current capacity and heat dissipation.

l Direct Pour: This method provides the strongest current-carrying capacity for pads or vias, making it ideal for high-power circuits. However, direct pours also enhance heat conduction, which, while beneficial for cooling components, can complicate soldering by rapidly dissipating heat, requiring higher soldering temperatures and larger soldering irons, which may reduce production efficiency.

l Orthogonal and 45-Degree Spokes: These methods reduce the contact area between the pad or via and the copper, slowing heat dissipation and making soldering easier. For low-power signal traces, orthogonal or 45-degree spokes are recommended, while direct pour is necessary for pads carrying high currents. The choice between orthogonal and 45-degree spokes is mainly aesthetic.

You may also like

Drone Circuit Board: What It Is and How to Make a Drone PCB Board?
Friday, August 16th, 2024

What is a Drone Circuit Board?

A drone circuit board refers to the electronic component board installed in a drone that controls and manages its various functions. It serves as the core control system of the drone, similar to how a brain functions in the human body. The drone circuit board controls all operations, including flight, photography, and video recording. It is the central system that coordinates all activities.

Depending on different functions and application scenarios, drone circuit boards can be classified into various types, such as flight control boards, video transmission boards, and power control boards. Among these, the flight control board can be considered a type of drone circuit board but is not equivalent to it. The flight control board mainly controls parameters such as flight direction, altitude, and speed, and adjusts the drone’s posture to ensure stable flight. The drone circuit board, however, not only controls flight but can also implement auxiliary functions such as GPS positioning and image transmission.

What Board is Used in Drones?

In drone design, the two most common types of circuit boards are rigid-flex boards and traditional PCB boards. Rigid-Flex PCB is a hybrid type of PCB that combines rigid and flexible circuit boards. It allows the board to bend and fold in tight spaces, which is particularly useful for compact drones that require a highly integrated design. Moreover, rigid-flex boards are lightweight and thin, which is advantageous for drone designers looking to enhance flight time and stability.

Traditional PCB Boards are another common type of circuit board used in drone design. These boards have strong mechanical strength, making them suitable for the core control units in drones, such as flight control boards and ESC boards (Electronic Speed Controllers).

Below are the main types of circuit boards commonly found in drones:

Control Circuit Board

The control circuit board is one of the most important boards in a drone. It typically consists of the main control chip, sensors, and electronic speed controllers (ESC). The main control chip acts as the brain of the drone, receiving wireless signals and controlling the flight posture and movement based on user commands. Sensors can detect the drone’s position and motion in real-time, ensuring stable flight control. The ESC adjusts the motor speed and direction, which directly impacts the drone’s flight.

Power Supply Circuit Board

The power supply circuit board is responsible for providing power to the drone, ensuring proper voltage and current. It must prevent issues like overcurrent, overvoltage, and overheating to maintain the drone’s performance.

Navigation Circuit Board

The navigation circuit board determines the drone’s position and direction, with the GPS module as the core component. GPS helps obtain satellite signals, calculating important information such as latitude, longitude, and altitude, to ensure precise navigation and positioning. The board may also include other sensors like barometers, gyroscopes, and accelerometers to enhance navigation accuracy.

Communication Circuit Board

The communication circuit board typically includes WiFi, Bluetooth, and 4G/5G modules, which allow the drone to connect with ground control stations or user devices for data transmission, remote control operations, and video streaming.

Why Use a Drone Circuit Board?

Besides the central chip, drone circuit boards serve many critical functions, such as power management and signal transmission. Let’s take a closer look at their functionality:

Power Management

The power management chip on a drone circuit board controls and regulates the power supply. Unlike regular circuit boards, the power management module in drones must be efficient, low-power, and lightweight. Since drones often need to fly for hours, improper design of the power management module can severely impact flight time and energy utilization.

Collecting data

The sensor chip on the drone circuit board is responsible for collecting data, such as GPS location, barometric pressure, and posture. The sensor chip processes data from wireless sensors and transmits it to the control chip for decision-making.

Control the drone

The control chip is the most vital part of the drone circuit board, managing and coordinating all aspects of the drone’s operation, including GPS navigation, servos, and motors. The microprocessor in the control chip uses algorithms to control flight while processing real-time sensor data.

Data Transmission

When capturing aerial photos or videos, the drone needs to send the recorded data to ground devices. The data transmission chip on the drone circuit board ensures that this information is transmitted to ground equipment. Many drones also support wireless network connections for seamless communication.

How to Make a Drone PCB?

To make a drone PCB, you’ll need to prepare the following materials:

  • STM32F405RGT6 microcontroller, which is stable and suitable for various drone applications.
  • 2.4G CC2500 wireless module based on the UART protocol for data communication with the remote control.
  • Sensors like accelerometers, gyroscopes, magnetometers, barometers, GPS, etc., to provide sensor fusion for precise drone control.
  • Power Module
  • Other components including resistors, capacitors, diodes, voltage regulators, and other basic circuit components.

Here is the way to create the drone PCB step by step:

1. Design

You can use PCB software to design the schematic and PCB layout, determining key parameters like circuit connections and component placement.

2. Printing and Etching

Print the designed circuit board pattern onto transparent stickers and attach them to copper sheets. After etching and removing the stickers, the circuit board will be ready.

3. Soldering

Solder the components onto the circuit board. It’s essential to leave adequate pads for soldering during the design phase.

4. Testing

Test the soldered circuit board to ensure normal functioning of the circuits.

What Should We Consider When Designing a Drone PCB?

  • Make sure enough power, ground, and data lines are allocated to each component to avoid signal interference and noise.
  • Take measures to protect components from static electricity during soldering.
  • Write clear and standardized comments in your program for easier modifications and debugging later.
  • Double-check that the board’s connections are in the correct order to prevent damage to the control board.

Is a Fuse Board the Same As a Distribution Board?

No, a fuse board and a distribution board serve different purposes in a drone’s electrical system.

Fuse board is designed to protect your components from power surges or short circuits. It contains fuses that blow if too much current flows through them, cutting off power to prevent damage.

Distribution board is simply distributes power from the battery to different components of the drone, such as the ESCs and flight controller. It doesn’t have the protective features of a fuse board.

In some designs, both can be combined into one board, but their functions remain distinct.

How can I Increase my Drone Power?

Increasing your drone’s power can improve performance, allowing it to carry more weight or fly faster. You can use below ways to increase the power:

  • Upgrade motors
  • Increase battery capacity
  • Use better propellers
  • Optimize power distribution

You may also like

Rigid flex pcb Design & Prototype Right the First Time
Monday, August 12th, 2024

rigid-flex printed circuit board ,Rigid flex pcb manufacturer. More than 5 years design team of 10 people. Quick proofing within 1 week. A 3,000-square-meter factory for small batch to mass production and assembly.

What is a rigid flex pcb?

Rigid flex pcb,rigid-flex printed circuit board,Rigid flex circuit are a hybrid construction flex circuit consisting of rigid and flexible substrates which are laminated together into a single structure. Each layer of rigid-flex circuit are electrically interconnected by plated through holes (PTH), which is different from a flexible circuit with FR4/PI stiffener on top or bottom of flex circuit only by the means of presensive or thermal senstive adhesive only, no PTH.

What is a rigid flex pcb?

Rigid-flex PCBs can be divided into single-sided boards, double-sided boards and multi-layer boards according to the number of conductive circuit layers. Multi-layer boards usually contain multiple rigid layers and flexible layers, and the circuits are connected and interconnected through interlayer connections.

Is Rigid flex PCB reliable?

  1. Design and manufacturing efficiency: Designers of rigid-flex boards can use a single component to replace a composite printed circuit board connected by multiple connectors, multiple cables and ribbon cables, which not only has stronger performance and higher stability, but also limits the scope of the design to one component, optimizing the available space by bending and folding the lines like a stacked paper swan.
  2. Space and weight optimization: In PCB prototyping for consumer electronics, the use of rigid-flex boards not only maximizes space use and minimizes weight, but also greatly improves reliability, eliminating many needs for solder joints and fragile and fragile wiring that are prone to connection problems. The design of this circuit board allows the size and weight of equipment and systems to be reduced while maintaining functionality.
  3. High stress environment adaptability: Rigid-flex boards also have high impact resistance and can survive in high stress environments, which makes it widely used in military, aviation and medical equipment.
  4. Excellent electrical performance: Rigid-flex boards provide excellent electrical performance, and good thermal conductivity makes components easy to cool. The lower dielectric constant of the flexible part allows for fast transmission of electrical signals, and the PI substrate has a higher glass transition temperature or melting point, which allows the components to operate well at higher temperatures.
  5. Assembly reliability: Rigid-flex boards reduce the hardware required for traditional rigid boards and flexible boards to be connected, such as traditional jumper sockets, etc., and can provide higher assembly reliability.

What is the difference between rigid flex and semi flex?

  1. Definition and structure
    Rigid-flexible board: It is a combination of soft board and hard board, that is, a thin layer of flexible bottom layer and rigid bottom layer are combined and laminated into a single component to form a circuit board1. It changes the traditional flat design concept and expands it to a three-dimensional space concept. It has both rigid layer and flexible layer and is a multi-layer printed circuit board.
    Semi-flexible board: It is a PCB used in the field of static bending obtained by combining controlled deep milling or rigid-flexible board processing technology (such as milling cover or opening window, etc.) in the standard hard board processing process2. It often uses FR4 material, first processes the PCB according to the normal process, and then mills the middle part that needs to be bent to make it flexible.
  2. Flexibility and application
    Rigid-flexible board: It has higher flexibility and can be bent, folded or rounded, and then integrated into various products, such as aerospace equipment, military aircraft, high-end medical equipment, digital cameras, portable cameras and high-quality MP3 players. ‌
    Semi-flexible board: Although it can be bent or curved, its flexibility is not as good as that of rigid-flexible board. It is mainly used in situations where static bending is required, such as endoscopes in medical equipment, injection needle tip protection circuit boards, and medical equipment temperature control circuit boards. ‌
  3. Processing and cost
    Rigid-flexible board: Due to the mixed use of multiple materials and multiple production steps, its processing time is longer and the production cost is higher. ‌
    Semi-flexible board: Although its processing process is also more complicated, its processing cost is lower than that of rigid-flexible board, and it is more suitable in some applications. ‌
  4. Features and advantages
    Rigid-flexible board: It has stronger performance and higher stability, can reduce space and weight, and improve the reliability of connection. ‌
  5. Semi-flexible board: It has the advantages of low cost, good dimensional stability, bendable three-dimensional installation to reduce space, and reduce the number of interfaces during assembly to improve reliability.‌

how do they add rigid layers to flex pcb?

  1. Design layout: Before starting the manufacturing process, the PCB design layout is first carried out to determine the location and connection method of the components. ‌
  2. Substrate preparation: Clean the laminate containing the copper layer to prepare for the subsequent manufacturing process. ‌
  3. Pattern generation: The generation of circuit patterns is completed by screen printing or photo imaging. ‌
  4. Etching process: The laminate with the circuit pattern is soaked in an etching tank or sprayed with an etchant solution for etching. ‌
  5. Mechanical drilling: Circuit holes, pads and via patterns are drilled using a precision drilling system or technology, such as laser drilling technology. ‌
  6. Copper plating process: Deposit the required copper in the plated vias to establish electrical interconnections between layers. ‌
  7. Covering layer application and lamination: Apply the covering layer material (such as polyimide film) and adhesive, and laminate under specific temperature, pressure and vacuum limits to ensure proper adhesion of the covering layer. ‌
  8. Apply stiffeners: Apply local additional stiffeners before additional lamination processes as required by the board design. ‌
  9. Flexible board cutting: Cut flexible boards from production panels using hydraulic punching methods or specialized punching knives. ‌
  10. Electrical testing and verification: Conduct electrical testing in accordance with IPC-ET-652 guidelines to confirm that the insulation, connection, quality, and performance of the circuit board meet the requirements of the design specifications.

What are the disadvantages of rigid flex PCB?

  1. Material damage or breakage: The flexible materials used in rigid-flex boards are susceptible to flexure and bending. Long-term use or improper handling may cause damage or breakage of the flexible part, resulting in an open circuit.
  2. Poor welding: The manufacture of rigid-flex boards requires welding processes. If the welding is poor or the solder joints are of poor quality, it may cause loose connections or solder joints to fall off, resulting in an open circuit.
  3. Excessive bending or stretching: Excessive bending or stretching during use may cause the connection wires or wires of the flexible part to be stretched excessively and break, causing an open circuit.
  4. Design defects: If the design of the rigid-flex board is unreasonable or defective, such as insufficient design of the overbending area or too small bending radius, the material of the flexible part may be damaged by excessive stress, resulting in an open circuit.
  5. Environmental factors: Under different environmental conditions, it may be affected by factors such as temperature, humidity, and chemicals. Long-term use in harsh environments may cause material aging or corrosion, resulting in an open circuit. ‌
  6. Damage during assembly: During the assembly process, improper operation or external force may cause damage to the connecting wires or wires of the flexible part, resulting in an open circuit.

Application fields of rigid flex PCB

  1. Automotive electronics: Rigid-flex boards are widely used in automotive electronic systems such as dashboards, navigation systems, and in-car entertainment systems in the automotive industry. Their flexibility and high reliability enable them to adapt to the complex spatial layout and vibration environment inside the car.
  2. Medical equipment: In the field of medical equipment, rigid-flex boards also have important applications, such as medical monitoring equipment, medical imaging equipment, etc. Its flexible part can adapt to different equipment shapes and size requirements, while having stable circuit connection performance.
  3. Aerospace field: Rigid-flex boards are usually used in aircraft dashboards, navigation systems, communication equipment, etc. in the aerospace field. Due to their light, thin and flexible characteristics, rigid-flex boards have become an ideal choice for aerospace equipment.
  4. Smart wearable devices: With the rapid development of smart wearable devices, rigid-flex boards are widely used in products such as smart watches and health monitoring equipment. They can be combined with curved display screens, sensors and other components to achieve a more humanized design.
  5. Industrial control field: In the field of industrial automation control, rigid-flex boards are often used in PLC controllers, robot control systems, sensor interfaces, etc. Its flexibility and reliability ensure the stable operation of the equipment in harsh environments.
Application fields of rigid flex PCB

Rigid flex pcb manufacturer

rigid flex pcb.rigid-flex printed circuit board,Rigid flex circuit are a hybrid construction flex circuit consisting of rigid and flexible substrates which are laminated together into a single structure. Each layer of rigid-flex circuit are electrically interconnected by plated through holes (PTH), which is different from a flexible circuit with FR4/PI stiffener on top or bottom of flex circuit only by the means of presensive or thermal senstive adhesive only, no PTH.

Rigid flex pcb manufacturer

Multilayer circuitry-from 3 to 14+ layers
Min LW/LS: 4mil/4mil
Adhesive-based and adhesiveless constructions, including thermoplastic and thermoset stiffener attachment.
Polyimide substrates: 1/2mil – 4mil
Copper: 1/3OZ – 2OZ, RA or ED type
Stiffeners include Polyimide (0.075-0.20mm), FR4 (0.15-2.0mm), and punched or formed metal parts (0.075-1.0mm)
Low-cost, conventional fabrication and lamination completed with PTH based plating
Screened inks, photo-imageable soldermasks, or laminated coverlay dielectrics
Surface finishes: ENIG, electroplated nickel/gold, immersion silver, tin,
EMI Shielding

how to design flex rigid pcb?

Rigid-Flex Circuit Design Guidelines

To form a rigid-flex, follow these considerations to ensure the best results.

Considerations When Designing Rigid-Flex Circuits

To produce a rigid-flex PCB with unmatched quality and functionality, you must follow the correct manufacturing specifications. This is the set guidelines and standards that manufacturers must consider when designing and manufacturing flexible circuit boards.

Determine Manufacturing Process and Materials Beforehand

Depending on the flexibility you require, you need to decide beforehand what materials to use and the methods to use. Example; When the board you are designing only needs to be folded during manufacturing and thereafter be in a fixed position without bending, you can decide the following

  1. Copper type and grade
  2. Manufacturing method
  3. Number of layers to be used.

On the other hand, if the board is for an application with frequent movement, vibration, and impact, you must be clear in choosing the following:

  1. Copper Coils
  2. Adhesives and
  3. Number of Layers

Place Copper Traces at Right Angles to Rigid-Flex

Copperworks is a great fit when placed on the right edge of the board. Avoid bending copper traces at corners as it will pull stress and may not create the best bend. For PCB flex that requires bending, use sharp radius bends to avoid smudging copper traces.

Provide adequate pad support for exposed copper

Repetitive stress from frequent bending can cause copper on the circuit to break away from the polyimide substrate. Support exposed copper with pads to prevent separation.

Use hatched polygons

Hatched polygons instead of solidified copper help maintain the flexibility of flexible PCBs.

Leave at least 1/2mm gap between copper ring and adjacent vias

1/2mm helps avoid fatigue caused by frequent bending. Placing vias in fixed areas of the board helps avoid frequent movement and bending, resulting in the best rigid-flex.

You may also like

What Does An Audio Board Do? – Best Technology
Friday, August 9th, 2024

An audio board, often referred to as a soundboard or mixer, is a crucial device in the world of sound engineering. Whether you’re working on a live concert, recording in a studio, or simply enhancing audio for a video production, understanding the role of an audio board is essential. This guide will walk you through what an audio board does, its various names, and how to set one up effectively.

What Does An Audio Board Do? - Best Technology

What Does an Audio Board Do?

An audio board, or soundboard, manages and controls audio signals. It’s used in many settings, from live concerts to recording studios. The primary function of an audio board is to mix different audio sources, such as microphones and instruments, to create a balanced sound output. This device allows sound engineers to adjust levels, equalize sound frequencies, and add effects to enhance the overall audio experience.

In more technical terms, an audio board receives input signals, processes them, and sends them to an output device. This processing can include adjusting volume levels, panning audio between speakers, and applying effects like reverb or delay. The result is a well-mixed audio output that sounds harmonious and professional.

What is Also Called an Audio Board?

An audio board goes by several names, depending on its use and context. Commonly, it’s known as a soundboard or mixing console. In professional settings, you might hear it referred to as an audio mixer or sound mixer. These terms are often used interchangeably, but they all refer to the same essential device that manages and manipulates audio signals.

What Does An Audio Board Do? - Best Technology

Other names include audio mixing board and professional mixing board. These names highlight the device’s role in combining multiple audio inputs into a single or multiple outputs. Whether you’re shopping for an audio board online or looking to upgrade your studio equipment, understanding these terms will help you find the right product for your needs.

What is the Working Principle of Audio Board?

The working principle of audio circuit refers to the process of audio signal transmission and processing in the circuit. In general, the frequency range of audio signals is 20Hz to 20kHz, and they are electrical signals used to transmit sound. The processing of audio signal includes amplification, mixing, filtering and so on.

Amplification refers to increasing the amplitude of the audio signal so that it can drive the speaker to produce a sound. The amplification process is generally achieved using an amplifier, the principle is to use the amplifier tube of the amplifier to amplify the input signal and then output it to the speaker.

Mixing refers to the process of mixing multiple audio signals into one signal. In a mixing circuit, multiple audio signals are mixed together through a mixer to output a composite signal. The mixer is generally composed of an operational amplifier and a mixer. The operational amplifier is responsible for adding multiple input signals, while the mixer is responsible for adjusting the volume ratio of each input signal.

Filtering refers to filtering the audio signal through a filter to remove unwanted frequency components. Filters are generally divided into low-pass filters, high-pass filters and band-pass filters. A low-pass filter only allows low-frequency signals to pass through, a high-pass filter only allows high-frequency signals to pass through, and a bandpass filter only allows signals in a certain frequency range to pass through.

Is a Sound Board the Same as a Mixer?

Yes, a soundboard and a mixer are essentially the same device. Both terms describe equipment used to blend and adjust audio signals. The term “mixer” is often used in professional audio production environments, while “soundboard” is more common in live sound settings.

The confusion between these terms arises from their varied applications. A soundboard is typically associated with live events, where audio engineers manage the sound in real-time. A mixer, on the other hand, might be used more broadly, encompassing both live and studio environments. Regardless of the term, the device’s primary function remains the same: to mix audio signals and produce a balanced sound output.

What is the Function of a Soundboard?

A soundboard, or audio mixer, plays a critical role in sound engineering by managing and manipulating audio signals. Let’s delve deeper into its functions:

  • Mixing Audio Signals
  • Equalization (EQ)
  • Volume Control
  • Panning
  • Adding Effects
  • Routing
  • Dynamic Processing
  • Monitoring

How Do You Hook Up a Soundboard?

Hooking up a soundboard needs to proceed several steps. Each step is the key point to make sure all audio sources are correctly connected and configured. Here’s a step-by-step guide:

  1. Prepare all necessary cables, microphones, instruments, and speakers.
  2. Plug your microphones and instruments into the input channels on the soundboard. Each channel corresponds to a specific input source.
  3. Connect the output channels of the soundboard to your speakers or recording devices. This usually involves using XLR or quarter-inch cables.
  4. Turn on the soundboard and all connected equipment.
  5. Adjust the input gain for each channel to ensure the signal is neither too weak nor too strong.
  6. Test each input and output to ensure everything is working correctly. Make necessary adjustments to the levels and EQ settings.
  7. Use headphones or monitor speakers to listen to the audio and make final adjustments.

How to Set Up a Sound Mixing Board?

Setting up a sound mixing board involves more than just connecting cables. Here are detailed steps to set up your sound mixing board effectively:

  • Plan Your Setup

Determine the layout of your equipment and where each input and output will be connected. This planning stage helps avoid confusion during the actual setup.

  • Label Everything

Label each input and output cable to know which source they correspond to. This step is crucial in complex setups with many audio sources.

  • Connect Your Inputs

Plug in microphones, instruments, and any other audio sources into the appropriate input channels on the mixing board.

  • Connect Your Outputs

Connect the main outputs to your speakers or PA system. Also, connect any auxiliary outputs to additional monitors or recording devices.

  • Power Everything On

Turn on your mixing board and connected equipment. Make sure to power on any external preamps or processors first if you’re using them.

  • Adjust Gain Levels

Set the gain for each input channel. Start with the faders at unity (0 dB) and adjust the gain until each input is at a proper level.

  • Set EQ and Effects

Adjust the EQ settings for each channel to achieve a balanced sound. Add effects as needed to enhance the audio.

  • Create a Mix

Use the faders to balance the levels of all input sources. Make sure each source is heard clearly without overpowering the others.

  • Monitor and Adjust

Continuously monitor the sound through headphones or monitor speakers. Make adjustments as necessary to maintain a balanced mix.

Best Technology has rich experience in the audio board manufacturing, we have served more than 2000+ customers and provide excellent turn-key solutions. If you are interested in the audio board pcb assembly, welcome to contact us.

You may also like

How to Read Circuit Boards and Schematics?
Wednesday, August 7th, 2024

How to read circuit boards and schematics is a basic skill for anyone interested in electronics. Whether you’re a beginner or a technician, knowing how to read these diagrams is crucial. In this blog, we would like to share the key points and components symbols in the PCB schematics.

How to Understand a PCB Board?

A printed circuit board is a basic of electronic components interconnected via conductive paths printed on a baseboard. We can see it everywhere. They connect and support various components using conductive tracks, pads, and other features. To understand a PCB, start by identifying its main sections: power supply, signal paths, and grounding. Look for the layout patterns, which often follow a logical flow.

Special Types of Circuit Boards

Circuit boards come in various types, each designed for specific applications and processes. Apart from the standard FR4 PCB, metal core PCB, ceramic PCB, rigid-flex PCB, there are some other special PCB uses different process. Here, we’ll explore them based on their unique manufacturing processes, including HDI, busbar, extra thin, IC substrate, high Tg, heavy copper, RF, and impedance control PCBs.

High-Density Interconnect (HDI) PCB

HDI PCBs are designed for compact and complex electronic devices. They feature higher wiring density per unit area compared to traditional PCBs. The process involves microvias, buried vias, and blind vias to create intricate pathways. HDI technology allows for more components on a smaller board, enhancing performance and reducing size. This type of PCB is commonly used in smartphones, tablets, and other high-tech gadgets. The HDI PCBs that Best Technology can make is:

  • 1+N+1
  • 2+N+2
  • 3+N+3

Busbar PCB

Busbar PCBs are specialized boards that handle high current loads efficiently. It belongs to the heavy copper PCB. They use thick copper layers to conduct electricity with minimal resistance. The busbar process involves integrating these thick copper bars within the PCB to distribute power uniformly. They are mainly used in the electric vehicles, power supplies and industrial machinery.

Extra Thin PCB

Extra thin PCBs are designed for applications where space and weight are critical constraints. These boards can be as thin as 0.2mm, allowing them to fit into slim devices like wearables and medical implants. The manufacturing process focuses on using thinner materials and precision etching techniques to achieve the desired thickness without compromising functionality.

IC Substrate PCB

IC substrate PCBs act as the base for integrated circuits (IC). They provide interconnections between the IC and the PCB. These PCBs are crucial in devices like processors, memory modules, and graphic cards, where precision and reliability are paramount.

High Tg PCB

High Tg (glass transition temperature) PCBs are designed to withstand higher temperatures. The Tg value indicates the temperature at which the PCB material transitions from a rigid to a soft state. High Tg PCBs use materials that has over 170 Tg value. So, they are widely used in automotive, aerospace, and industrial applications.

Heavy Copper PCB

Heavy copper PCBs feature significantly thicker copper layers compared to standard PCBs. The process involves plating additional copper to achieve thicknesses of 3oz/ft² or more. These boards handle high currents and thermal cycles, making them ideal for power electronics, motor controllers, and high-power distribution systems.

Radio Frequency (RF) PCB

RF PCBs are designed for high-frequency applications. They use special materials like PTFE (Teflon) to minimize signal loss and interference. This kind of PCB always requires precise control over dielectric thickness and conductor widths to make sure optimal signal integrity. RF PCBs are essential in communication devices, radar systems, and microwave equipment.

What Do the Numbers on a Circuit Boards Mean?

Numbers and letters on a circuit board represent component values, reference designators, and sometimes manufacturing codes. Reference designators (like R for resistors, C for capacitors) help identify each component. The numbers often indicate the order of placement or specific values (e.g., R1, R2 for the first and second resistors).

In addition, some designers prefer to design series number on the PCB board, like 202400001…202400002. For this kind of numbers, they are always aim to easy identification during the assembly or testing.

How to Read Circuit Boards?

Reading a circuit board involves several steps. First, familiarize yourself with the board’s layout and components. Identify key parts such as the microcontroller, resistors, capacitors, and connectors. Trace the pathways or traces to understand the connections. Use the reference designators to match components with their schematic symbols.

Electronic symbols follow standardized guidelines to ensure consistency. The most common standards include IEEE, IEC, and ANSI. These symbols represent various components like resistors, capacitors, diodes, and transistors.

  1. VCC – the positive power supply.
  2. GND – ground or negative power supply.
  3. R – resistor.
  4. C – capacitor.
  5. L – inductor.
  6. Q – transistor or field-effect transistor (FET).
  7. JP – connector or plug/socket.
  8. IC – integrated circuit or chip.
  9. + / – – input/output terminals of a signal.
  10. NC – no connection or an unused pin.

How Do You Read a Circuit Schematic for Beginners?

Read circuit diagram drawings can be consulted by experienced masters. Generally, the first look when reading a circuit schematic is look at the main loop. And then look at the control loop, the control loop requirements are from top to bottom or from left to right. The circuit diagram mainly consists of four parts: component symbol, connection, node and comment/note.

1. Component Symbols

These represent the actual components in the circuit. Their shapes may not resemble the actual components and can even be completely different. However, they generally indicate the characteristics of the components, and the number of pins matches the actual components.

2. Connections

These represent the wires in the actual circuit. While they appear as lines in the schematic, they are often not lines but various shapes of copper foil blocks on commonly used printed circuit boards (PCBs). For example, many connections in a radio schematic may not be line-shaped on the PCB but rather in specific shapes of copper film.

3. Nodes

These indicate the connections between multiple component pins or wires. All component pins and wires connected to a node are conductive, regardless of the number.

4. Comment/note

These are very important in a schematic. All the text in the schematic can be classified as notes. A close look at the schematics reveals annotations everywhere, used to indicate component models, names, and other information.

Best Technology offer top-quality advanced PCB boards, from prototypes to mass production. Our range includes FR4 PCBs of any Tg, FPC, ceramic PCBs, aluminum PCBs, Teflon PCBs, and copper-base PCBs. Every product and service is traceable and verified with ISO, IATF, RoHS, UL, and REACH certifications. Enjoy free samples for bulk orders, complimentary functional testing, and fast delivery.

You may also like

What is Metal Core Printed Circuit Board and Its Advantages?
Tuesday, July 23rd, 2024

Metal core printed circiut boards are used where a large of heat are generated in the circuit, and the heat needs to be dissipated quickly to avoid overheat. These boards offer good thermal conductivity and dimensional stability. The aluminum core can reduce the overall weight of your board.

What is Metal Core Printed Circuit Board?

A metal core printed circuit board (MCPCB) is a type of PCB that incorporates a metal core, usually aluminum or copper, as its base material. This core helps to enhance the board’s thermal management capabilities. Unlike traditional PCBs made of fiberglass (FR4), MCPCBs are designed to dissipate heat more effectively, making them ideal for applications where heat dissipation is crucial.

MCPCBs are also referred to as insulated metallic substrate (IMS), or insulated metal PCBs (IMPCB), thermal-clad PCBs. A typical metal core PCB is made of thermal insulating layer (dielectric layer), metal base and copper foil.

The basic constructure of a metal core circuit board includes:

  • Silkscreen
  • Solder mask (S/M)
  • Circuit layer (copper foil layer)
  • Dielectric layer
  • Metal core base

What are Metal Core PCBs Used For?

Metal core PCBs are popular because of its good thermal management. It utilizes in various applications that demand efficient heat dissipation and high thermal performance. Here are some common applications that metal core printed circuit board will be used in.

  • LED lighting

MCPCBs are widely used in LED lighting systems due to their excellent thermal management properties. LEDs generate a significant amount of heat, and metal core PCBs help to dissipate this heat effectively, ensuring longer lifespan and consistent performance of the LEDs.

  • Power supplies

High-power supply units benefit from MCPCBs as they can handle the heat generated by power components. This helps in maintaining the stability and efficiency of the power supply over time.

  • Automotive electronics

In the automotive industry, MCPCBs are used in various electronic control units (ECUs), lighting systems, and other high-power applications. The robust nature of MCPCBs makes them suitable for the harsh conditions experienced in automotive environments.

  • Industrial equipment

Industrial machinery and equipment that operate under high temperatures or require high power output use MCPCBs for their thermal management capabilities. This ensures the reliability and longevity of the equipment.

  • Telecommunications

Telecommunications equipment, such as base stations and routers, use MCPCBs to manage the heat generated by high-speed and high-frequency operations, ensuring uninterrupted performance and reliability.

  • Consumer electronics

High-performance consumer electronics, including laptops, smartphones, and gaming consoles. They install with MCPCBs to manage heat and improve device performance and lifespan.

What are the Advantages of Metal Core PCB?

Metal core PCBs are preferred for several reasons, primarily revolving around their superior heat dissipation capabilities and mechanical strength. Here are some main advantages of metal core PCBs.

  • Superior thermal management
  • Mechanical strength
  • Compact design
  • Enhanced performance
  • Improved reliability
  • Higher recyclability
  • Cost Efficiency
  • Dimension stability
  • Size reduction
  • Longer lifetime

What Metal is Used in PCBs?

The choice of metal in PCBs significantly affects their thermal and mechanical properties. The most commonly used metals in MCPCBs are aluminum and copper. Here’s a closer look at these materials:

Aluminum

          • Thermal Conductivity: Aluminum has a thermal conductivity of approximately 1.0 to 2.0 W/mK, making it an excellent material for heat dissipation.
          • Cost-Effective: Aluminum is relatively inexpensive compared to other metals, making it a cost-effective choice for many applications.
          • Lightweight: Aluminum is lighter than copper, which can be beneficial in applications where weight is a concern.
          • Corrosion Resistance: Aluminum naturally forms a protective oxide layer, enhancing its resistance to corrosion.

          Copper

          • Thermal Conductivity: Copper has a higher thermal conductivity than aluminum, ranging from 3.0 to 5.0 W/mK, providing superior heat dissipation.
          • Electrical Conductivity: Copper is also an excellent conductor of electricity, which can improve the electrical performance of the PCB.
          • Durability: Copper is more durable and resistant to wear and tear compared to aluminum, making it suitable for more demanding applications.
          • Higher Cost: Copper is more expensive than aluminum, which can increase the cost of the PCB but is justified in applications requiring superior performance.

          Other Metals

          In some specialized applications, other metals like stainless steel or alloys might be used, but these are less common due to their specific properties and higher costs.

          What is the difference between FR4 PCB and Aluminum PCB?

          Aluminum PCB is a material based on aluminum base material, coated with an insulating layer and other conductive layers on the aluminum base material. FR4 is a glass fiber reinforced laminate, made of multi-layer fiber cloth and resin composite. In the following, we will introduce the difference between aluminum substrate and FR4 in terms of thermal conductivity, mechanical strength, manufacturing difficulty, application range and thermal expansion coefficient.

          1. Aluminum substrate has good heat dissipation, and its thermal conductivity is about 10 times that of FR4.

          2. The mechanical strength and toughness of the aluminum substrate are better than FR4, which is suitable for installing large components and making large-area pcb boards.

          3. The production of aluminum substrate requires more process steps, and its production process is more complex than FR4, and the production cost is higher than FR4.

          4. The aluminum substrate is suitable for high-power electronic products such as LED lighting, power supplies, inverters and solar inverters, and FR4 is suitable for low-power electronic products such as televisions, telephones and electronic game consoles.

          5. The thermal expansion coefficient of aluminum substrate is close to that of copper foil, which is smaller than that of FR4, which is good for ensuring the quality and reliability of the circuit board.

          https://www.youtube.com/watch?v=KFQNdAvZGEA&list=PLh7eQ1tIPsW456K51PERNxBMK0r9lRg1e

          How to Design Metal Core PCB?

          Designing a metal core PCB is a complex process that includes several crucial steps. During the design, we should ensure the board meets the thermal, electrical, and mechanical requirements of the application. Below is a detailed guide to the MCPCB design process.

          1. Define the Application Requirements

          Before starting the design process, it’s essential to clearly define the requirements of your application. This includes understanding the thermal, electrical, and mechanical needs of the project. Determine the maximum operating temperature and the amount of heat that needs to be dissipated, ensuring the MCPCB can handle the thermal load effectively. Specify the electrical characteristics such as current load, voltage levels, and signal integrity requirements to ensure the board can deliver the necessary performance.

          2. Select the Core Material

          As mentioned above, there are two common metal materials used in this industry: aluminum alloy and copper core. They have unique characteristics and properties when used in device. So. choosing the appropriate metal core material is crucial for the performance of your electronic device. This table provides a side-by-side comparison of aluminum alloy and copper core materials, helping to choose the appropriate material when designing MCPCBs.

          PropertyAluminumCopper
          Thermal Conductivity1.0 – 2.0 W/mK3.0 – 5.0 W/mK
          Electrical ConductivityLower than CopperHigh
          WeightLightHeavy
          CostLowerHigh
          Mechanical StrengthGoodExcellent
          Corrosion ResistanceNatural Protective Oxide LayerRequires Additional Protection
          Thermal Expansion CoefficientHigherLower
          MachinabilityGoodMore Difficult
          Environmental ImpactRecyclableRecyclable
          Application AreasLED Lighting, Consumer Electronics, High-PerformanceElectronics, Industrial Equipment

          3. Determine the Layer Stack-Up

          The layer stack-up defines the arrangement of the different layers in the PCB. A typical MCPCB stack-up includes:

          • Top Copper Layer: The conductive layer where components are mounted.
          • Dielectric Layer: An insulating layer that separates the copper layer from the metal core. It has good thermal conductivity to transfer heat from the components to the metal core.
          • Metal Core: The central layer made of aluminum or copper, which acts as a heat spreader.
          • Bottom Copper Layer (optional): Used in double-sided MCPCBs for additional routing of traces.

          4. Design the Circuit Layout

          The circuit layout includes placing components and routing traces on the PCB. Key considerations include strategically placing heat-generating components to ensure efficient heat dissipation and keeping sensitive components away from high-heat areas. Trace routing should minimize electrical interference and maintain signal integrity, using wider traces for high-current paths to reduce resistance and heat generation. Implementing thermal vias enhances heat transfer from the top copper layer to the metal core by using plated through holes that connect the copper layer to the metal core, facilitating better heat dissipation.

          5. Design for Manufacturability (DFM)

          Ensuring that your design can be efficiently manufactured is critical. Maintain adequate clearances between traces, pads, and other features to meet MCPCB manufacturing capabilities and avoid short circuits. Use standard drill sizes to reduce manufacturing complexity and cost. Apply a solder mask to prevent solder bridges and protect the copper traces from oxidation. Use clear and legible silkscreen markings for component identification and assembly instructions. You can communicate with your supplier and ask for a capability chart, so that can save much time on design phase.

          6. Prototype and Test

          Once the design is validated, create a prototype of the MCPCB and conduct thorough testing. Measure the actual thermal performance under operational conditions to verify the simulation results. Test the functionality of the PCB in the intended application environment to ensure it meets all performance requirements. Conduct reliability tests such as thermal cycling, vibration testing, and humidity testing to assess the durability of the MCPCB.

          Best Technology – A Leading MCPCB Manufacturer in Asia

          With 18+ years of experience in the PCB industry, Best Technology has a deep understanding of the complexities involved in MCPCB production. Our team of experts is adept at designing and manufacturing MCPCBs that deliver optimal performance. Best Technology offers customized turn-key solutions tailored to the specific needs of our clients. Whether it’s a unique design requirement or a specific material preference, we provide flexible options to meet diverse demands.

          Contact Best Technology, get your quote right now to make your own metal core circuit boards!

          You may also like