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pcb support metallic

August 9th, 2024

pcb support metallic are mainly used to support and fix circuit boards to ensure their stability and reliability. The following is a summary of the materials and types, functions and uses of PCB metal support columns, as well as their market supply.

pcb support metallic

Materials and types: ‌
1.The materials are mainly brass, stainless steel and other metals, which have good conductivity and corrosion resistance. ‌
2.Types include hexagonal double-pass copper columns, single-head isolation copper columns, external hexagonal PCB metal external thread spacing screw columns, etc. ‌
Functions and uses: ‌
1.Support and fix circuit boards to prevent them from moving or deforming during use. ‌
2.Provide circuit connection points to achieve electrical connection between circuit boards. ‌
Market supply: ‌
1.There are many suppliers in the market that provide PCB metal support columns of different specifications and materials. ‌
2.Suppliers usually provide customized services to meet the specific needs of customers. ‌

Materials and types: ‌

What is a PCB support column

PCB support columns, also known as circuit board support columns, are mainly used to support and connect circuit boards and are widely used in computer connectors, various PCB assemblies, and electronics. These support columns are usually made of insulating materials such as plastic and nylon, and have good insulation properties and mechanical strength. They have various designs, including aircraft type, flat bottom type, hexagonal type, and other shapes to meet different installation and usage requirements.

What is a PCB support column

Function of PCB support column

PCB support columns play an important role in multiple application scenarios. ‌
To ensure the stability and reliability of PCB in various application scenarios, the support columns are used to support and position the sub-board, ensure that the sub-board is placed flat on the carrier, and thus improve the welding effect between the sub-board and the carrier. ‌In the injection mold, the support column supports the B plate to prevent it from being deformed by pressure during injection molding. ‌In the design of large-load electric cylinders, the support column plays a role in enhancing structural strength, improving pressure resistance, optimizing load capacity, maintaining accuracy and stability, and extending service life. ‌
In addition, in the communication engineering PCB welding and docking support device, the support column is used to clamp and fix the docking plug to ensure that the communication engineering PCB can be stably docked and welded. ‌
In summary, the main function of the PCB support column is to provide stable support and positioning to ensure the stability and reliability of the PCB in various application scenarios.

How to choose PCB support columns?

Choosing a suitable PCB support column requires comprehensive consideration of multiple factors such as performance, material, size, and cost
1.Performance requirements: Determine the performance required by the support column according to the application scenario, such as load-bearing capacity, corrosion resistance, and high temperature resistance. ‌
2.Material selection: Common materials include metal, plastic, etc. Metal support columns are strong and durable, but may be susceptible to corrosion; plastic support columns are light and have good insulation, but may not be strong enough.
3.Size and shape: The size and shape of the support column should match the specifications and installation requirements of the PCB to ensure stable support and connection. ‌
4.Cost and budget: Under the premise of meeting performance requirements, consider the cost and budget of the support column and choose a cost-effective product

PCB support column material?

PCB support columns are widely used in the electronics field. They are mainly used to support and connect circuit boards. ‌ Common PCB support column materials include nylon, plastic, metal (such as brass, stainless steel, aluminum) and resin, etc. Nylon and plastic are the most commonly used materials due to their good insulation performance, easy processing and low cost. Metal materials such as brass and stainless steel are selected in certain specific applications due to their good mechanical strength and conductivity. ‌ Resin materials are also used in the production of some PCB support columns due to their insulation and processing properties.

What Does An Audio Board Do? – Best Technology

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.

 hs code printed circuit board,pcb boards hs code

August 9th, 2024

The customs code for printed circuit boards is 8534-0000. 8534 is the classification code for this item, and 0000 represents the sub-classification code under this item. In the actual customs declaration process, it is necessary to select the corresponding sub-classification code according to the specific classification standard of printed circuit boards.

hs code printed circuit board

hs code printed circuit board:85340000
PCBs made of FR-4 material (i.e. silicon tetrachloride fiberglass board) are classified under HS code 8534.00.00
hs code printed circuits with more than six layers:85340010
hs code printed circuits with four layers or less:85340090
The HS code for PCB (printed circuit board) is 8534001000.
HS code of PCBA is 8543709990

HS code of PCBA is 8543709990

How do you classify printed circuit boards?

According to different classification standards, printed circuit boards can be divided into many types, such as single-sided boards, double-sided boards, multi-layer boards, rigid boards, flexible boards, etc.

The role of HS codes for printed circuit boards

HS codes are a way for customs to classify goods, and are also an important basis for import and export statistics. As an electronic component, printed circuit boards also need to be HS coded so that customs can accurately classify and manage them.

Types of HS codes for printed circuit boards

There are two main HS codes for printed circuit boards: 85340010 and 85340090. Among them, 85340010 is mainly used for printed circuits with more than six layers, while 85340090 is mainly used for printed circuits with four layers or less. The difference between the two codes lies in the number of layers of the printed circuit board, because printed circuits with more than six layers require higher technical requirements and more complex production processes.

How to choose the correct HS code

The specific HS code may vary depending on product specifications, materials and other factors. Therefore, in actual operation, it is recommended to consult relevant departments or professionals according to the specific situation to ensure accuracy. If you are not sure which HS code to choose, you can consult the printed circuit board manufacturer or relevant industry associations for more professional advice.

How do I do a customs declaration?

  1. Declare the code accurately. Select the sub-classification number corresponding to the printed circuit board according to the actual situation to avoid penalties or detention caused by coding errors.
  2. Provide a complete production process. The production process of the printed circuit board needs to be provided in the customs declaration, including the procurement, production, processing, testing and other links of the materials, so as to facilitate the customs inspection of the printed circuit board.
  3. Declare accurate materials and technical parameters. The technical parameters such as the substrate, copper foil thickness, board thickness, drilling diameter, line width, line spacing, etc. used in the printed circuit board need to be accurately declared in the customs declaration.
  4. Re-declaration is required if the dominant production process is changed. If the dominant production process is changed, it is necessary to re-declare to the customs and re-make the customs declaration.
  5. Comply with relevant national quality standards. Printed circuit boards need to meet relevant national quality standards, such as ISO, UL, etc.

hs code electronic,How do I find an HS code?The HS code for PCB (printed circuit board) is 8534001000. PCBs made of FR-4 material (i.e. silicon tetrachloride fiberglass board) are classified under HS code 8534.00.00

What Do You Know About Copper Weight in PCB?

August 8th, 2024

Copper weight refers to the amount of copper per square foot of the PCB surface, measured in ounces per square foot (oz/ft²). However, the term “copper thickness” is also commonly used. So, how do copper weight and thickness relate to each other?

Copper thickness is determined by rolling a specific weight of copper over a 1 square foot area. For instance, if 1 ounce of copper is spread out over an area of 1 square foot, the resulting thickness of the copper foil is approximately 1.37mils or 0.0348mm.

What Do You Know About Copper Weight in PCB?

What is the Standard Copper Weight for PCB?

The standard copper weight in PCBs typically ranges from 1 oz/ft² to 3 oz/ft². This measurement refers to the weight of copper per square foot. In metric terms, it translates to approximately 35 µm to 105 µm thickness. The choice of copper weight depends on the application and the current-carrying requirements of the PCB. For standard consumer electronics, 1 oz/ft² is often sufficient. However, power electronics and high-current applications may require heavier copper.

What is Copper Thickness in PCB?

PCB typically feature a layer of copper foil bonded to a glass epoxy substrate. Common copper foil thicknesses are 18μm, 35μm, 55μm, and 70μm. The most frequently used thickness is 35μm. In practice, copper foil thicknesses used domestically generally range from 35μm to 50μm, with thinner options like 10μm or 18μm and thicker options like 70μm also available.

For substrates that are 1mm to 3mm thick, the copper foil is typically 35μm thick. On substrates less than 1mm thick, the copper foil is about 18μm thick, while on substrates thicker than 5mm, the copper foil is around 55μm thick.

If a PCB has a copper foil thickness of 35μm and a trace width of 1mm, the resistance per 10mm length of the trace is approximately 5mΩ, and the inductance is about 4nH. When a digital integrated circuit on the PCB operates with a di/dt of 6mA/ns and a current of 30mA, the estimated noise voltage generated in the circuit due to resistance and inductance for every 10mm length of the trace is 0.15mV and 24mV.

Copper Weight vs. Copper Thickness

Here’s a chart illustrating the relationship between copper weight, copper thickness in mils, and copper thickness in millimeters (mm).

Copper Weight (oz/ft²)Copper Thickness (mils)Copper Thickness (mm)
0.50.70.018
11.40.035
22.80.070
34.20.105
45.60.140
57.00.175
38.40.210

How Do You Calculate Copper Weight in PCB?

Calculating copper weight involves determining the thickness of the copper layer. Here’s a simple method:

  1. Measure the thickness of the copper in micrometers (µm).
  2. Use the conversion factor: 1 oz/ft² equals 35.56 µm.
  3. Multiply the thickness by the conversion factor to get the weight in oz/ft².

For example, if the copper thickness is 70 µm, the calculation is:

Copper weight (oz/ft²)=70um/35.56um/oz≈2oz/ft2

You can use a PCB weight calculator to simplify this process, like PCBWay Calculator, Altium PCB Layout Weight Calculator.

How Much Copper is in a PCB?

The amount of copper in a PCB varies depending on the copper weight and the size of the board. For instance, a 10 cm x 10 cm PCB with a copper weight of 1 oz/ft² will have less copper than the same size board with 3 oz/ft² copper weight. To estimate the total copper, you need to know the board area and the copper thickness.

Total copper (grams)=Area (cm²)×Copper thickness (µm)×8.96×10-3

The factor 8.96 x 10^-3 converts the volume to weight, considering copper’s density.

What is the Density of Copper in PCB?

Copper’s density is a constant value of 8.96 g/cm³. This density is crucial for calculating the weight of copper in a PCB. Knowing the density helps in accurately estimating the amount of copper in your PCB, which is essential for both design and manufacturing processes. The density remains constant regardless of the copper weight or thickness, providing a reliable basis for various calculations in PCB design.

Why Copper Thickness is Important for PCB?

In the PCB manufacturing process, copper thickness is a very important factor. The correct copper thickness can ensure the quality and performance of the circuit board, but also ensure the reliability and stability of electronic products. We have listed the following points to show why copper thickness is so important for PCBs.

1. Electrical conductivity

Copper thickness determines the electrical conductivity of the circuit board. As you know, copper is an excellent conductive material, and its thickness directly affects the conductive effect of the circuit board. Thinner copper layer may reduce the electrical conductivity of PCB, and resulting in attenuation of signal transmission or instability of current. And if the copper layer is too thick, although the electrical conductivity will be very good, but will increase the cost and weight of the circuit board. Additionally, thicker copper thickness is easy to lead to serious glue flow, the medium layer is too thin, and increase the manufacturing process difficulty. Therefore, for normal PCB, the copper thickness is generally not recommended to do 2oz copper thick, otherwise you can choose Heavy Copper PCB.

2. Heat dissipation

Copper thickness also has an important impact on the heat dissipation performance of the circuit board. The copper layer is the thermal conductivity layer of the circuit board, and its thickness determines the heat dissipation effect. If the copper layer is too thin, it may cause heat to be unable to conduct and dissipate effectively, increasing the risk of overheating of components. Therefore, the copper thickness of the PCB cannot be too thin, in the PCB design process, we can also lay copper in the blank area to assist the heat dissipation of the PCB board.

3. Improve reliability

Copper thickness also has an important impact on the reliability and stability of the circuit board. The copper layer not only acts as the conductive layer and thermal layer, but also the support and connection layer of the circuit board. The appropriate copper thickness provides sufficient mechanical strength to prevent the board from bending, breaking, or opening welding during use. At the same time, the appropriate copper thickness can ensure the welding quality of the circuit board and other components, reducing the risk of welding defects and failures.

How to Select Suitable Copper Weight for PCB?

Selecting the suitable copper weight depends on several factors:

  • Current Carrying Capacity

Higher currents require thicker copper to prevent overheating. Calculate the required trace width and copper thickness based on the maximum current your PCB will carry.

  • Thermal Management

Thicker copper improves heat dissipation, essential for high-power applications. Consider the thermal requirements of your components and ensure the PCB can manage the heat effectively.

  • Mechanical Strength

Heavier copper can enhance the board’s structural integrity. For applications where the PCB will face mechanical stress or flexing, thicker copper provides added durability.

  • Cost Considerations

Thicker copper increases material costs, so balance performance needs with budget constraints. While thicker copper offers many benefits, it also comes with higher manufacturing costs. Evaluate whether the additional expense is justified for your specific application.

  • Signal Integrity

For high-frequency applications, maintaining signal integrity is crucial. Thicker copper can help reduce resistance and signal loss, improving overall performance.

  • Environmental Factors

Consider the operating environment of the PCB. For harsh conditions, thicker copper may offer better protection against corrosion and environmental stressors.

For most applications, 1 oz/ft² copper is adequate. For power electronics or where higher currents are involved, consider 2 oz/ft² or more. Consult with your PCB manufacturer for recommendations based on your specific use case. They can provide insights into the optimal copper weight for your design, considering both performance and cost-effectiveness.

How to Read Circuit Boards and Schematics?

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.

What is Tda7294 amplifier board &tda7294 datasheet

August 7th, 2024

TDA7294 is a class AB monolithic audio amplifier integrated circuit launched by SGS-THOMSON Microelectronics in the 1990s. It swept away the raw, cold and hard sound of previous linear integrated amplifiers and thick film integrated amplifiers, and is widely used in HiFi fields, such as home theaters, active speakers, high-performance TVs and other fields.

The chip adopts a 15-pin dual-row asymmetric plug-in package, the differential input stage is composed of bipolar transistors, and the driver stage and power output stage use DMOS field-effect transistor semiconductor technology. This hybrid semiconductor manufacturing process allows TDA7294 to take into account the advantages of bipolar signal processing circuits and MOS power tubes, and the playback sound is very friendly (it is praised by audiophiles as a “tube-flavored amplifier”); the built-in silent standby function, short-circuit current and overheating protection functions make its performance more perfect. It can be used in HiFi home audio, active audio, high-performance TVs and other fields.

Tda7294 amplifier board

tda7294 amplifier board

tda7294 amplifier board PCBA

  1. This circuit is an official standard circuit, stable and reliable.
  2. The filter uses a large electrolytic capacitor with a withstand voltage of 50V and a capacity of 2200uf.
  3. Power supply voltage: dual 12-36V ring transformer, dual 32V ring transformer is recommended
  4. Output power: 85W*1 undistorted rated power, peak power 100W
  5. Can easily drive speakers above 100W, speaker impedance: 4-8 ohms
  6. PCB size: 50*50mm
tda7294 amplifier board

Basic parameters:
Power supply: dual 18-28V AC
Power: 2X80W+160W subwoofer
Circuit board size: 218x98MM
Potentiometer function: low frequency frequency adjustment, subwoofer volume. Left and right channel volume, treble, bass.

Adopting the new laser dark word TDA7294
The power filter uses 6 63V3300UF capacitors, and the rectifier uses a 25A imported rectifier flat bridge.
PCB uses 1.6mm thick double-sided board, 2.0 ounces copper thickness, and full tin spraying process to ensure good passing performance of large and small currents.
Fever component assembly, the subwoofer part consists of two new TDA7294 BTL output,
The low-pass filter is designed according to the frequency adjustable design of home theater style (50-150HZ), with strong power!
The left and right channels are served by two TDA7294 respectively, and the input coupling capacitor uses the German imported WIMA 2.2UF coupling capacitor, which makes the sound sweeter!
The signal-to-noise ratio of the board is also very high, and even if you put your ear close to the speaker, you can’t hear the AC noise! ​​It is the best choice for upgrading 2.1 amplifiers!

TDA7294 datasheet

TDA7294 datasheet
TDA7294 datasheet

TDA7294 Main Features

Wide supply voltage range: ±10V ~±40V
High output power: 70W (up to 100W)
Standby and mute functions
Noiseless ON/OFF switch
Low noise and low distortion
Short circuit protection and overheat protection

TDA7294

Pin function
Pin 1 is the standby terminal;
Pin 2 is the inverting input terminal;
Pin 3 is the positive input terminal;
Pin 4 is grounded;
Pins 5, 11, and 12 are empty pins;
Pin 6 is the bootstrap terminal;
Pin 7 is +Vs (signal processing part);
Pin 8 is -Vs (signal processing part);
Pin 9 is the standby pin;
Pin 10 is the mute pin;
Pin 13 is +Vs (final stage);
Pin 14 is the output terminal;
Pin 15 is -Vs (final stage)

DIY Production

1) The first step is to get the PCB. Here you can make the PCB yourself by DIY ironing method. Since the PCB is easy to make, the PCB design is kept single layer only, or you can get ready-made quality PCB from best.or custom tda7294 amplifier board.
2) After the PCB is completed, carefully mount all small components like jumpers, resistors, diodes, etc. to the PCB and trim their terminals, then solder them to the PCB first, because there are many components on this board, so it is better to solder them one by one
3) After installing the small components, install the large components like capacitors, fuse holders, rectifiers to the PCB and solder them. (Don’t install the power filter capacitor, 22000uF capacitor for now. Completed in the following steps)
4) After that, it’s time to mount all 7 ICs to the PCB and solder them.
5) Now properly mount the heat sink on the IC using insulating MICA and insulating plastic shoulder washers. Remember to use good quality thermal paste between the heat sink and IC.
6) After mounting the IC on the heat sink. Check the continuity between the heat sink and the IC back plate using a multimeter. There should not be any continuity between them. Please note the heat sink isolation
7) Now mount the cooling fan to the PCB using cable ties or any other suitable method.
The board assembly is now complete. Clean the track side of the board using IPA (Isopropyl Alcohol) or cleaning flux and then power the board using a 20-0-20 VAC transformer or a 24-0-24 VAC transformer.

Which one has better sound quality, TDA7294 or LM3886? Voltage AC 28v

LM3886 has better bass because its maximum current can reach 10A, which means it can drive a 2-ohm box without any problems. From the parameters alone, LM3886 is worse than 7294. And it is true in practice, especially for bass. If the transformer is OK, it feels very powerful. 7294 is not as good as 3886 in bass. The current is large when it comes to bass. 7294 itself has overcurrent protection. When the current reaches a certain level, it starts to limit the output current. However, 7294 is better in treble.

The origin of inches and how to convert millimeters to inches

August 7th, 2024

Inches to MM conversion

In the imperial system, 12 inches is 1 foot, and 36 inches is 1 yard.
1mil=1/1000inch=0.00254cm=0.0254mm.
1inch=2.54cm=25.4mm=1000mil
1 inch=2.54cm=25.4mm.

10 mm = 0.393700787 inches
50 mm =1.96850394 inches

1400mm in inches
1400 mm = 55.1181102 inches

1500 mm to inches
1500 mm = 59.0551181 inches

1800mm to inches
1800 mm =70.8661417 inches

Origin of the inch

The word “inch” comes from the Old English word “ynce”, which comes from the Latin word “uncia” (meaning “one twelfth”).
In the 14th century, King Edward II of England promulgated the “standard legal inch”; its regulations were: the length of the three largest grains of wheat selected from the middle of the barley ear and placed end to end in a row is 1 inch.

mm or inches in the PCB industry

(including the substrate and all copper layers, solder mask and silk screen), either millimeters or inches can be used as units. However, 1.6 mm is not the only choice, and the thickness of the PCB can vary depending on the specific application, ranging from 0.3 mm to 4.0 mm1.
In PCB design, for design and layout units such as traces, pads, spacing and grids, the imperial unit “thou” (one thousandth of an inch) should be used instead of millimeters. For mechanical manufacturing unit requirements such as apertures and PCB board sizes, millimeters can be used. This shows that when designing PCBs, you need to be familiar with the conversion relationship between the imperial unit “thou” and the metric unit millimeter. ‌
In summary, the units used in the PCB industry depend on the specific application scenarios and requirements. When describing the thickness of the PCB board, millimeters or inches can be used as units, while in design and layout, the imperial unit “thou” should be used to adapt to design requirements.

PCB package size

PCB length units usually refer to the shortest distance between components on the PCB. Common length units are inches, centimeters and millimeters. For example, the minimum PCB length unit for the 0805 package size is 1 inch, while the minimum PCB length unit for the 0402 package size is 0.25 inches. In addition, there are some other commonly used PCB package sizes, such as 0101 package size, 0201 package size, 0302 package size, etc.

PCB package size is a standard size for mounting and connecting electronic components on PCBs. The following are the most commonly used device PCB package sizes:
1.0805 package size: This package size is used for electronic components of 8 inches (about 20 cm) in size, including transistors, capacitors, inductors and other small components.
2.0402 package size: This package size is used for electronic components with a size of 4 inches (about 10 cm), including transistors, capacitors, inductors and small components.
3.0603 package size: This package size is used for electronic components with a size of 6 inches (about 15 cm), including transistors, capacitors, inductors and small components.
4.1206 package size: This package size is used for electronic components with a size of 12 inches (about 30 cm), including transistors, capacitors, inductors and small components.

The unit of PCB length is usually millimeter (mm) or inch (inch), while the unit of copper foil thickness is OZ (ounce), which is about 35um or 1.35mil. When designing the PCB of the op amp circuit, factors such as layout, wiring, power decoupling, and heat dissipation design need to be considered to ensure signal integrity and stability.

What is a 5.1 amplifier board?

August 7th, 2024

A 5.1 amplifier board is a sound amplifier that can expand the current and voltage of an audio signal to make the sound louder. In addition, a 5.1 amplifier board also has a multi-channel processing function, which can output audio signals through multiple channels to enhance the sound field effect, making listening to music, watching movies, etc. more three-dimensional and realistic.
Compared with traditional 0 and 1 amplifiers, in addition to being able to connect two front speakers and two rear speakers, a 5.1 amplifier board can also connect a center speaker and a subwoofer, making the bass of music or movies more prominent and the sound deeper.
5.1 amplifiers are widely used in home theater systems. By combining with projectors, TVs and other equipment, a theater environment with excellent audio-visual effects can be created. In addition, for music lovers, a 5.1 amplifier board is also an indispensable device that can not only maximize the effect of music, but also allow people to experience the charm of music in an immersive way.

What is a 5.1 amplifier board?

5.1 Basic parameters of the amplifier board

Working mode: Class D
Quiescent current: 50mA
Working efficiency: 90%
Rated output power: 2200W+400W Frequency response: 20Hz to 20KHz Working voltage: DC24V-42V( Recommended voltage: DC42V Maximum output current: 10A PCB size: 114109MM
Potentiometer center distance: 21.5MM 21.5MM 21.5MM from left to right
Original TPA3223 is used

TPA3223 2.1 Digital Bluetooth 5.1 3034 Amplifier Board


1.The front input capacitor and interstage coupling capacitor use ELNA BP capacitor 10UF, the electrolytic capacitor signal main circuit uses Taiwan famous brand, and the main filter capacitor uses imported electrolytic capacitor 1000UF , ensuring strong and continuous power support.
2.The resistors are made of high-precision chip resistors, and the main circuit uses a five-ring metal film resistor with an accuracy of ±1%, which ensures a good signal-to-noise ratio for the whole machine.
3.The PCB uses a 1.6mm thick double-sided board, 2.0 ounces of copper thickness, and a full tin-spraying process to ensure good passing performance of large and small currents.
4.The fully enclosed dust-proof potentiometer is used, which has more stable performance and is more durable than ordinary potentiometers.
5.The red-gray ring high-current inductor and the fully shielded audio-specific output inductor are used to ensure a crisp and powerful sound.
The Bluetooth uses Qualcomm QCC3034 5.1 version Bluetooth module

5.1 amplifier board

5.1 amplifier board of working principle

  1. The core function of the amplifier board is to increase the amplification factor of the signal while protecting the circuit from damage. The amplifier board is usually used for isolation and current amplification between the programmable logic controller (PLC) and the input device or output device to improve the load capacity of the PLC and protect the PLC from faults such as overvoltage, overload, and load short circuit.
  2. The working principle of the amplifier board is based on the amplifier circuit, using electronic components with amplification characteristics, such as transistors. When the tiny current at the input end changes, a large current change will occur at the output end, and the change at the output end is several to hundreds of times greater than the change at the input end. The characteristic of this amplifier circuit is that only one potential point is amplified, and the other potential point is grounded by default. In addition, the integrated circuit (IC) is also an important part of the amplifier board. It integrates many transistors, resistors, capacitors and other components on a small piece of semiconductor silicon single crystal, and uses isolation technology to insulate them from each other in electrical properties, thereby realizing signal amplification and processing.

For example, an analog signal amplifier board can connect multiple sensors, collect differential signals and amplify them to the required multiples through an amplifier circuit. The board can work normally in the temperature range of -15℃ to 70℃, and the humidity can reach 90%, which is suitable for various harsh environments. This amplifier board is widely used in industrial automation, smart home, medical equipment and other fields to ensure stable signal transmission and processing

5.1 amplifier board of working principle

The role of the amplifier board

The main functions of the amplifier board:

  1. This is because some process control equipment such as proportional valves can only receive analog voltage or current signals. Therefore, in order to ensure that these devices can correctly receive and respond to the signals sent by the PLC, an intermediate amplification link, namely the amplifier board, is required.
    It can properly amplify the signal output by the PLC D/A module to make the proportional valve work normally.
  2. The amplifier board is also called the IO relay board. Its main functions include isolation, current amplification, and providing additional I/O channels. It can improve the load capacity and reliability of the PLC system and prevent the PLC host from being damaged due to overvoltage, overload or load short circuit. ‌
  3. The amplifier board is widely used in the field of industrial automation. It can not only improve the load capacity and reliability of the PLC system, but also protect the output or input points of the PLC.
  4. The amplifier board can save cabinet space, increase installation speed, facilitate maintenance and replacement, and has protection circuits and built-in insurance, which makes it difficult to damage the amplifier board itself and the load.
  5. The amplifier board can also play the role of amplifying interference, because its input and output are photoelectrically isolated, and the PLC will not be burned out due to high-voltage impact load.
    These features make the amplifier board play a vital role in industrial automation systems.

Application of 5.1 amplifier board

5.1 channel amplifiers are mainly used in home theater systems to provide surround sound audio output and an immersive listening experience for the audience. ‌
5.1 channel amplifiers are an indispensable component of home theater systems. They can provide five full-band channels and one low-frequency effect channel. Through carefully designed audio processing, the audience can feel the sound from different directions, thereby enhancing the immersion of movies or concerts.

Application of 5.1 amplifier board

In addition to home theater applications, 5.1 channel amplifiers are also suitable for professional audio systems, such as conference rooms, performance venues, etc., where high-quality audio output is required. ‌In these occasions, 5.1 channel amplifiers can ensure stable signal transmission and high-quality restoration to meet professional-level audio needs. ‌

In short, the 5.1 channel amplifier board provides multi-channel audio output, bringing a more realistic and three-dimensional sound experience to viewers or listeners, playing an important role in both home entertainment and professional applications.

FAQs About 5.1 amplifier board

Does the 5.1 amplifier front panel consist of 6 front panels?

  1. A true 5.1 should have 6 input interfaces (marked as: 5.1IN) and 6 speakers including a subwoofer.
  2. 5.1 is an independent 6-channel amplification and 6-channel speaker restoration, and of course an independent 5.1-channel sound source is required.
  3. The 5.1 speaker requires the amplifier to have an independent 6-channel amplifier. Virtual ring. Winding into multiple channels

How many power amplifiers are there in a 5.1 channel amplifier?
Two situations, the first is 5.1 full-channel power amplification, that is, 6 channels, but in this case the power of the bass channel is small, which can drive 6~8-inch bass, but it can’t drive large ones.
The second is 5-channel power amplification, except for the bass channel, the other channels are power amplified, the bass channel only provides a level signal, and the signal enters the active subwoofer amplifier board to drive the subwoofer, which is more common.

Can the 5.1 channel amplifier board use dual DC?

  1. Ordinary transistor power amplifiers use DC. What do you mean by “using dual DC power”? Does it mean using a backup power supply? … Using a backup power supply is completely possible.
  2. In addition, there are power amplifiers that are powered by [positive and negative symmetrical power supplies]. Such power amplifiers must use DC positive and negative symmetrical power supplies.

Can I make a 5.1 with two 2.1 amplifier boards?


One of them is used for 2.1 (the analog subwoofer circuit is removed as bass amplification), and the other is used for surround channels (remove the subwoofer circuit and change to center). After merging, it is 5.1. The 6 amplification channels must be connected to the 5.1 decoding output.


Can a 5.1 pre-stage board be used with a 2.0 amplifier?
It can definitely be used. The pre-stage board only plays the role of audio adjustment and does not perform power amplification. The input audio signal can be connected to the amplifier after being adjusted and output by the pre-stage board. For the 5.1 channel, just select 2 of the output signals.

How Much Does A PCB Board Cost?

August 6th, 2024

When communicate with clients, they always ask why the PCB board are so expensive? Is there any basis for that? Actually, the price of PCBs are made specifically according to its manufacturing process, layers, complexities and so on. Today, Best Technology is deeply sharing the composition of PCB cost. Welcome to keep reading.

Why is PCB Board So Expensive?

The cost of a PCB can sometimes seem high due to several reasons. Firstly, the complexity of the design plays a significant role. High-density interconnect (HDI) PCBs, multi-layer PCBs, and those requiring advanced materials or special finishes can drive up the cost. Additionally, stringent quality control measures and the need for precise manufacturing processes add to the expense.

Another factor is the cost of raw materials. Copper, laminates, and specialty substrates can vary in price, affecting the overall cost of the PCB. Furthermore, labor costs in the region where the PCB is manufactured, along with overhead costs such as utilities and facility maintenance, contribute to the final price.

What Factors Affect the PCB Board Cost?

PCB board can cost from $10 to $500 to produce. Buyers are always amazing that why PCB cost so high? But they don’t know there are numerous factors a manufacturer considers in determining PCB costs. If you are in the market to design a PCB, this guide provides factors to consider that could increase or decrease the cost of circuit boards.

  • Manufacture technology

The specific technology used in the PCB can significantly impact the cost. Advanced technologies such as HDI (High-Density Interconnect), embedded busbar or flexible PCBs often require more complex manufacturing processes, which can increase the cost.

  • Material Type

The type of materials used for the PCB, such as standard FR4, high-frequency laminates, or other specialty substrates, can influence the cost. Higher quality or specialized materials typically cost more.

  • IPC Grade

The IPC standards and grades indicate the quality and reliability requirements of the PCB. In electronics manufacturing, printed circuit boards are divided into three levels: level 1, level 2 and level 3. These grades reflect the quality level of each board type, from the lowest (Level 1 standard) to the highest (Level 3 standard). This classification system was developed and defined by IPC and is specified in the IPC-6011 series.

  • Circuit Design

The complexity of the circuit design, including the number of layers, trace width, and spacing, affects the cost. More intricate designs require more precision and advanced techniques, leading to increased expenses.

  • PCB Size & Yield

The physical dimensions of the PCB and the yield rate during production play a role in the overall cost. Larger boards or designs with lower yield rates (more defects) will typically cost more to produce.

  • Material Thickness

The thickness of the materials used in the PCB construction, such as the substrate and copper layers, can impact the cost. Thicker materials may be more expensive and require more resources to process.

  • Copper Thickness

The thickness of the copper used in the PCB, measured in ounces per square foot, can affect the cost. Thicker copper layers provide better electrical performance but are more expensive.

  • Stack-up

The method of layering and stacking the materials in the PCB, known as the stack-up configuration, can influence the cost. Complex stack-ups with multiple layers and specific arrangements can be more costly to manufacture. Read our another post of How Can I Reduce and Optimize the Cost of My PCB in A Best Way?

Manufacturing Process of A Standard PCB

How Much Does A PCB Board Cost?

PCB Design and Layout

The manufacturing process begins with the design phase, where engineers use CAD (Computer-Aided Design) software to create the PCB layout. This includes defining the circuit paths, components, and layers, ensuring the design meets the electrical and mechanical requirements.

Once the design is finalized, a photomask is created, which is a transparent film with the PCB design printed on it. The PCB substrate, typically made of FR4, is then coated with a light-sensitive material called photoresist.

Drilling

Precise holes are drilled into the board for through-hole components and vias using computer-controlled drilling machines. The board is cleaned and deburred to remove any rough edges or debris from the drilling process.

Plating and Copper Deposition

A thin layer of copper is deposited on the surface of the board and inside the drilled holes through an electroless plating process, providing a conductive base. Additional copper is electroplated onto the board, building up the thickness of the copper traces and plated through-holes.

Pattern Transfer

The photomask is placed over the photoresist-coated substrate and exposed to ultraviolet (UV) light. The UV light hardens the photoresist where the design allows light to pass through, and the board is then developed to wash away the unhardened photoresist, leaving behind the desired circuit pattern.

Etching

The PCB undergoes an etching process using a chemical solution to remove unwanted copper, leaving only the copper traces that form the circuits. The remaining hardened photoresist is then stripped away to reveal the clean copper pattern.

Applying Solder Mask

A layer of solder mask is applied to the board to protect the copper traces from oxidation and prevent solder bridges during assembly. The solder mask is cured using UV light, hardening it and making it durable.

Surface Finish/Surface Treatment

A surface finish is applied to the exposed copper areas to protect them and facilitate soldering. Common finishes include HASL (Hot Air Solder Leveling), ENIG (Electroless Nickel Immersion Gold), and OSP (Organic Solderability Preservatives).

Outline Routing

One the surface treatment finish, it will be routed according to the manufacturing file by CNC machine. And then individual PCBs are cut from the larger panel using routing or V-scoring, depending on the board design and requirements.

Electrical Testing & FQC

The PCB undergoes electrical testing to check for short circuits, open circuits, and other defects. This is typically done using a flying probe tester or a bed-of-nails tester. Then the board is visually inspected for any cosmetic defects or anomalies, and further tests and inspections are performed to ensure the PCB meets all specified requirements and standards. Below you can see the full manufacturing process video of a PCB:

Best Technology – A 18+ Years Experience PCB Manufacturer

When you are looking for a reliable PCB manufacturer, considering Best Technology. We have transparent price and 5years quality warranty. We 24/7 hours online and welcome all the technical questions and PCB inquiries. Contact us for more!

How to Check PCB with a Multimeter?

August 5th, 2024

Common PCB failures are mainly concentrated on components such as capacitors, resistors, inductors, diodes, transistors, MOSFETs, integrated chips (IC), and crystals. Some obvious damages can be visually detected, while others require the use of tools. Today, let’s learn how to troubleshoot PCB faults using a multimeter.

How to Check PCB with a Multimeter?

How Will You Diagnose a Faulty PCB By Visually?

For some printed circuit boards, we can check by our naked eyes. Here are some common ways to follow:

1. Check the condition of components

When you get a faulty PCB, first observe if there are any obvious component damages, such as burnt or swollen electrolytic capacitors, burnt resistors, and damaged power devices.

2. Inspect the soldering of the PCB

Check if the printed circuit board (PCB) is deformed or warped; if there are any loose or poorly soldered joints; if the copper cladding on the PCB is lifted, burnt, or blackened.

3. Examine the component plug-ins

Ensure the correct orientation of integrated circuits, diodes, and the PCB power transformer.

How to Check PCB with a Multimeter?

Before you start testing your PCB, ensure you have the right tools and environment. Here’s a checklist to get you started:

1. Safety First: Wear anti-static gloves and ensure you are working on an anti-static mat to prevent damage to the PCB.

2. Multimeter Selection: Choose a multimeter with the ability to measure voltage, resistance, and continuity. A digital multimeter is preferred for accuracy.

3. Visual Inspection: Examine the PCB for visible signs of damage such as burnt components, broken traces, or solder bridges.

4. Power Off the Board: Always test the PCB with the power off to avoid any electrical hazards and damage to the multimeter.

How Do You Test Individual Components on a PCB?

Testing individual components like resistors, capacitors, and diodes can pinpoint the exact failure. Here’s a general approach:

  • Diode
  • Transistor
  • MOSFET
  • Electrolytic Capacitors

How to Test Diodes?

1. Set the MF47-type multimeter to measure resistance.

2. Place the red and black probes on the two ends of the diode and read the value.

3. Swap the probes and measure again.

4. Judge based on the two measurements: the forward resistance of small power germanium diodes is 300-500Ω, silicon diodes are about 1kΩ or larger. The reverse resistance of germanium diodes is tens of kilo-ohms, and silicon diodes are above 500kΩ (values are much smaller for high-power diodes). A good diode has low forward resistance and high reverse resistance, and the larger the difference, the better.

How to Check PCB with a Multimeter?

5. If both forward and reverse resistances are very low, the diode is short-circuited; if both are very high or infinite, the diode is open-circuited and needs to be discarded.

How to Test Transistors?

1. Set the digital multimeter to the diode mode.

2. Measure the PN junction with the probes. If it conducts forward, the displayed value is the forward voltage drop of the PN junction.

3. Determine the collector and emitter: measure the forward voltage drop of the two PN junctions, the larger drop is the emitter (e), and the smaller drop is the collector (c). If the red probe is connected to the common terminal, the transistor is NPN type, and the common terminal is the base (b); if the black probe is connected to the common terminal, the transistor is PNP type, and the common terminal is the base (b).

4. For in-circuit testing, measure the forward and reverse resistance of the PN junction to determine if the transistor is damaged. If the branch resistance is larger than the forward resistance of the PN junction, there should be a clear difference between the forward and reverse resistances, otherwise, the PN junction is damaged.

How to Check PCB with a Multimeter?

The Way to Test MOSFETs?

1. Connect the black probe to the drain (D) and the red probe to the source (S), the resistance should be 500-600.

2. Without moving the black probe, touch the gate (G) with the red probe, then measure the source (S) again; it should conduct.

3. Connect the red probe to the drain (D), touch the gate (G) with the black probe, then measure the source (S); the resistance should be the same as the first measurement, indicating the MOSFET is working normally.

How to Test Electrolytic Capacitors?

1. Select the appropriate range on the MF47-type multimeter based on the capacitor’s capacity. Use R×1K range for capacitors below 47μF, and R×100 range for those above 47μF.

2. Connect the red probe to the negative lead and the black probe to the positive lead of the capacitor.

3. On initial contact, the multimeter needle will deflect right and then gradually return to the left until it stops at a certain position (close to infinity). This value is the capacitor’s forward leakage resistance; the larger the value, the better the capacitor’s performance.

4. Swap the probes and repeat the process. The measured value will be the reverse leakage resistance, slightly smaller than the forward leakage resistance.

5. If no charging phenomenon occurs (the needle doesn’t move), the capacitor is either open or short-circuited internally. If the resistance is very small or zero, the capacitor is leaky or has broken down and cannot be used.

This is the end of this article, if you want to know more about it, welcome to contact us.