Posts Tagged ‘fpc’

What is a high temperature resistance flexible PCB?

Tuesday, October 22nd, 2024

A high temperature resistant flexible PCB is a flexible printed circuit board that can maintain stable performance in a high temperature environment. It is usually composed of a flexible substrate, a conductive layer, and a cover layer. It has the characteristics of being bendable, foldable, and lightweight, and can withstand high temperatures without affecting its electrical and mechanical properties.

What is the maximum temperature for a flex PCB?

The high temperature resistance of a flexible PCB mainly depends on its substrate material. Generally speaking, the maximum temperature that a flexible PCB can withstand can reach 280 degrees in a short period of time, but the long-term temperature is generally between 120 degrees and 150 degrees. ‌

What is a high temperature resistance flexible PCB?

Different types of flexible PCB materials have different tolerances to temperature. PI is a commonly used flexible PCB substrate material that has excellent heat resistance and stability. It can maintain performance in the range of -200 degrees to 300 degrees, but the long-term use temperature is generally between 120 degrees and 150 degrees. ‌

In addition, the glass transition point of solder mask is about 110 degrees, so special attention should be paid to the temperature limit of these materials when designing flexible PCBs. ‌

What temperature should flexible PCB soldering be?

‌The optimal temperature range for flexible PCB soldering is 290-310 degrees Celsius. This temperature range is suitable for most flexible PCB soldering operations and can ensure soldering quality and component reliability.

In specific operations, the soldering time should be kept within a few seconds to prevent damage to the pads of the PCB board. Accurate temperature management is essential to ensure the solder joint quality and circuit performance of the PCB board. The soldering temperature may vary for different types of flexible PCBs.

What is high Tg PCB?

‌High Tg PCB refers to PCB materials with higher glass transition temperature (Tg). ‌ Tg is the temperature point at which the material changes from glass to rubber state. High Tg materials can still maintain good mechanical strength and dimensional stability at high temperatures. ‌

The main advantages of high Tg PCB include:

‌Heat resistance‌: High Tg materials can still maintain good mechanical strength and dimensional stability at higher temperatures and are suitable for high temperature environments. ‌

‌Moisture resistance‌: High Tg materials have low moisture absorption. Even after being heated after moisture absorption, they can maintain good mechanical strength and adhesion, reducing the risk of failure caused by moisture‌.

‌Chemical resistance‌: High Tg materials have better chemical stability at high temperatures and are not easy to decompose‌.

‌Dimensional stability‌: When the temperature changes, the dimensional changes of high Tg materials are small, ensuring the accuracy of PCB‌.

Application scenarios of high Tg PCB include:

Lead-free manufacturing process‌: In highly functional and multi-layered electronic products, high Tg materials can ensure the stability and reliability of PCB in lead-free processes‌.

‌High temperature environment‌: In applications that need to withstand high temperature environments, such as computers, mobile communication devices, etc., high Tg PCBs can ensure stable operation of the equipment‌.

What are the disadvantages of flexible PCB?

The main disadvantages of flexible PCB include:

‌High one-time initial cost‌: Since flexible PCBs are designed and manufactured for special applications, the initial circuit design, wiring and photographic plate costs are high.

‌Difficult to change and repair‌: Once a flexible PCB is made, it must be changed from the base map or the compiled photolithography program, so it is not easy to change. Its surface is covered with a protective film, which must be removed before repair and restored after repair, which is a more difficult task‌.

How thick is the copper in a flex PCB?

The copper foil thickness in a flexible PCB is usually around 0.1mm. The copper foil thickness of a flexible PCB is generally 0.1mm, which is one of its common specifications‌.

In addition, the copper foil thickness of a rigid PCB has a wide range, and common thicknesses include 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1.0mm, 1.2mm, 1.6mm, 2.0mm, etc.‌. The copper foil thickness of a rigid PCB can be adjusted according to demand. For example, in an environment where high current and high power are required, the copper foil thickness may be higher‌.

Flexible PCB materials usually include polyester film, polyimide film, and fluorinated ethylene propylene film, etc. These materials are widely used in curved and flexible circuit designs in electronic devices‌.

Why are Flex PCBs so expensive?

First, material cost is one of the main factors affecting the price of flexible PCBs. Flexible PCBs mainly use special materials such as polyimide (PI) and polyester film, which have excellent heat resistance and electrical properties, but are more expensive.

Second, manufacturing process is also an important reason for the high cost of flexible PCBs. The production process of flexible PCBs includes multiple complex links such as exposure, development, etching, lamination and testing. High-precision manufacturing processes, such as fine line etching and precise alignment, require advanced equipment and technology, which increases production costs.

Design complexity is also a key factor. The design and manufacture of flexible PCBs involve multiple processes, such as etching, copper plating, drilling, etc. The higher the complexity of the process, the higher the manufacturing cost.

Finally, market demand also affects the cost of flexible PCBs. Mass production can effectively reduce unit costs, while small batch or customized production may lead to higher costs.

What is rigid-flex PCB vs flex PCB?

The main difference between rigid-flex PCB and flexible PCB lies in their structure and application scenarios. Rigid-flex PCB combines the characteristics of rigid PCB and flexible PCB, while flexible PCB is made entirely of flexible materials.

Rigid-flex PCB is a circuit board that combines rigid board and flexible board, and is usually used in areas where both rigidity and flexibility are required. This type of circuit board uses flexible materials in specific areas and remains rigid in other areas to meet complex design requirements.

Flexible PCB is made entirely of flexible materials and is usually used in applications that require high flexibility and space saving. Flexible PCB uses flexible materials such as polyimide, allowing the circuit board to be easily bent and folded in a small space. This type of PCB is widely used in modern smart devices such as smartphones, tablets and wearable devices to achieve smaller size and more complex functions.

What is the difference between FR4 and flex PCB?

The main difference between FR4 and flexible PCB lies in their materials, structure and application scenarios. FR4 is a rigid PCB substrate, mainly composed of glass fiber and epoxy resin, with good electrical properties and mechanical strength, suitable for applications requiring high stability and reliability. Flexible PCBs are highly flexible and bendable, suitable for applications with limited space or frequent bending.

FR4 features and applications:

FR4 is currently the most common PCB substrate. FR4 has good electrical properties, with a dielectric constant between 4.5 and 4.8, suitable for medium and low frequency applications; in terms of thermal performance, its thermal expansion coefficient is about 14-17ppm/°C, and its heat resistance can reach 260°C; in terms of mechanical properties, FR4 has high bending strength and tensile strength, suitable for manufacturing processes such as drilling, etching, and copper plating.

Due to its stability and reliability, FR4 is often used in applications such as display screens and reverse cam screens that require high stability.

Flexible PCBs features and applications:

Flexible PCBs (FPCs) are mainly made of materials such as polyimide and are highly flexible and bendable. They are often used in applications with limited size or frequent bending.

The design of flexible PCB is relatively simple, but when rigidity needs to be increased for easy installation or assembly, reinforcement plates such as PI, FR-4 or steel sheets are used.

Due to the high flexibility of flexible PCBs, they are often used in devices that require frequent movement or deformation, such as touch sensors and automotive lighting systems.

As a new type of PCB in the electronics field, high-temperature resistant flexible PCBs have gradually become a popular choice in the electronics field with their excellent high-temperature resistance, bendability, foldability, light weight, stable electrical performance, and good mechanical properties. High-temperature resistant flexible PCBs play an important role in applications in high-temperature environments such as aerospace, automotive electronics, industrial control, and medical equipment.

What is a flex board?

Flexible board is a printed circuit board made of flexible insulating substrate, also known as flexible printed circuit board (FPC). This circuit board has many advantages that rigid printed circuit boards do not have, such as it can be bent, wound, folded freely, and can withstand millions of dynamic bending without damaging the wires. Flexible circuit boards provide excellent electrical performance, meet the design needs of smaller and higher density installations, help reduce assembly processes and enhance reliability. It is the only solution to meet the requirements of miniaturization and mobility of electronic products, which can greatly reduce the volume and weight of electronic products and adapt to the needs of electronic products developing towards high density, miniaturization, and high reliability.

Comprehensive understanding of flex board

The main feature of the flexible board is that its substrate is usually polyimide or polyester film. This material has good elasticity and a certain degree of softness, which allows the flexible board to move and stretch arbitrarily in three-dimensional space, realizing the integration of component assembly and wire connection. In addition, the flexible board also has the characteristics of high wiring density, light weight, thin thickness and good bendability, making it the preferred choice in many application scenarios.

The application of flexible boards is very wide. For example, in new energy vehicles, the FPC solution has become the main choice for most new models. FPC is integrated with CCS (integrated busbar system) and is connected with copper and aluminum busbars and plastic structural parts to form electrical connection and signal detection structural components.

What is a Flexboard made of?

Flexible boards are made of polyimide or polyester film. ‌

Flexible circuit board (FPC) is a printed circuit board with high reliability and excellent flexibility. Its substrate is mainly polyimide or polyester film. This material selection gives FPC a variety of superior properties, including high wiring density, light weight, thinness and good bendability. These characteristics of FPC enable it to meet the needs of electronic products to develop in the direction of high density, miniaturization and high reliability.

Specifically, the substrate characteristics of FPC include:

‌Polyimide‌: This is a high-performance polymer with excellent mechanical properties, electrical properties and thermal stability. It is often used to manufacture flexible circuit boards because it can provide excellent flexibility and durability.

‌Polyester film‌: As a lightweight material, the application of polyester film in FPC provides good insulation performance and certain mechanical strength while maintaining overall lightness and thinness.

The choice of these two materials together ensures that the application of FPC in electronic devices can provide excellent electrical performance, meet the design needs of smaller and higher density installation, and help reduce assembly processes and enhance reliability.

Which flex material is best?

The best material for flexible PCB boards is polyimide. Polyimide has extremely strong toughness and scalability, and can meet the requirements of bending, folding, twisting, etc. in various shapes, which makes polyimide an ideal material for flexible PCB boards. In addition, polyimide also has good impedance control and signal integrity, ensuring the high reliability and stability of flexible PCB boards. Therefore, for application scenarios that require high flexibility and reliability, polyimide is the preferred flexible PCB material.

How many types of flex board are there?

There are four main types of flexible boards:

Single-sided flexible board: This is the most basic type of flexible circuit board, in which only one side has conductive lines. It is usually used for low-density and low-complexity applications, such as printer inkjet cartridges and computer memory.

Double-sided flexible board: This type of circuit board has conductive lines on both sides, and the electrical connection between the two sides is achieved through metallized vias.

Multi-layer flexible board: Multi-layer FPC consists of several layers of conductive lines and insulating materials, and the electrical connection between the layers is achieved through blind holes, buried holes or through holes.

Rigid-flex combination flexible board: This type combines a rigid substrate and a flexible substrate, and a conductive connection is formed through metallized holes. Rigid-flexible combined flexible boards meet the needs of electronic products to develop in the direction of miniaturization, high frequency, high speed and multi-function.

These different types of flexible boards are widely used in consumer electronics, automotive electronics, medical equipment, aerospace and defense, etc. according to their specific application requirements and design complexity.

What is the thickness of a flex board?

The thickness of a flexible circuit board (FPC) usually ranges from 0.1mm to 0.2mm. ‌This thickness range applies to single-layer and double-layer flexible circuit boards. For multi-layer flexible circuit boards, due to their complex manufacturing process and high cost, the thickness is uncertain.

The thickness range of the reinforcement board is wider, from 0.05mm to 0.1mm for thin reinforcement boards to 0.2mm to 0.5mm for thick reinforcement boards, and even ultra-thick reinforcement boards with a thickness of more than 0.5mm. The thickness selection of these reinforcement boards depends on the design requirements, the use environment and the required mechanical strength.

The material of flexible circuit boards usually includes polyimide (PI), and its thickness generally ranges from 12.5um (0.5mil) to 125um (5mil), and common specifications include 25um (1mil) and 12.5um (0.5mil). This information shows that the thickness of flexible circuit boards can be adjusted according to specific application requirements and designs, from thin to thick reinforcement boards, to meet different mechanical strength and stability requirements.

In general, the thickness selection of flexible circuit boards is very flexible and can be customized according to specific application scenarios and design requirements. Whether it is a single-layer, double-layer or multi-layer flexible circuit board, its thickness can be adjusted as needed to ensure the best electrical performance and mechanical strength. ‌

Why are Flex PCBs so expensive?

The high price of flexible PCBs (flexible circuit boards) is mainly caused by factors such as its material cost, the complexity of the manufacturing process, and technical requirements. ‌

‌Material cost‌: The main substrates of flexible PCBs include polyimide (PI) and polyester (PET). Polyimide has excellent heat resistance and electrical properties, but the price is higher; polyester has lower cost, but the performance is slightly inferior. In addition, the conductive layer is usually composed of copper foil, and factors such as foil thickness, copper purity and quality will also affect the cost.

‌Manufacturing process‌: The manufacturing process of flexible PCB is complex, including multiple links such as exposure, development, etching, lamination and testing. The process accuracy and equipment level of each link will affect the production cost‌.

‌Technical requirements‌: The design complexity, special requirements and gold finger surface treatment methods of flexible PCB in the production process will affect the cost. Complex circuit design requires more design time and process control, while special requirements such as high temperature resistance, moisture resistance, and bending resistance require different processes and difficulties, which increase the manufacturing cost‌.

‌Size and circuit structure‌: The cost of flexible PCB is also affected by size and circuit structure. Larger size and complex circuit structure will increase manufacturing cost.

In summary, the high cost of flexible PCB is mainly due to the combined effect of factors such as high material cost, complex manufacturing process, high technical requirements, and complexity of size and circuit structure.

Conclusion:

Compared with traditional hard boards, flexible boards have higher flexibility and bendability, adapt to various complex shapes and spatial layouts, and make circuit board design more flexible and diverse. With the advantages of small size and light weight, it greatly reduces the size and weight of the device, making it more convenient to carry electronic equipment. For the design and manufacture of various flexible circuit boards, you can contact BEST Technology, and we will provide you with comprehensive and best quality services.