Fumax

The High Temperature PCB Design Specification Guide is a comprehensive set of guidelines that regulates and guides PCB design in high temperature environments, aiming to ensure the stability and reliability of PCBs in high temperature environments.

Overview

With the rapid development of electronic technology, electronic equipment is increasingly used in high-temperature environments. In order to ensure the normal operation and reliability of electronic equipment in high-temperature environments, special high-temperature PCB design specifications are required. This guide aims to provide designers with a complete set of high-temperature PCB design specifications to ensure the stability and reliability of PCBs in high-temperature environments.

High Temperature PCB Material Selection

1. Substrate material: The substrate material of high-temperature PCB should have excellent high temperature resistance, good mechanical strength and electrical properties. Commonly used high-temperature substrate materials include ceramic substrates, metal substrates, etc. Among them, ceramic substrates have excellent high temperature resistance, but the cost is high; metal substrates have better heat dissipation performance and mechanical strength.
2. Insulating material: The insulating material of high-temperature PCB should have excellent high temperature resistance, good insulation performance and mechanical strength. Commonly used high-temperature insulation materials include polyimide (PI), polytetrafluoroethylene (PTFE), etc.
3. Conductor material: The conductor material of high-temperature PCB should have excellent high temperature resistance, good conductivity and solderability. Commonly used high-temperature conductor materials include gold, silver, copper, etc. Among them, gold has excellent high temperature resistance and electrical conductivity, but the cost is high; copper has lower cost and good electrical conductivity.

High Temperature PCB Design Principles

1. Thermal design: In PCB design, factors such as heat source distribution, heat dissipation methods, and air flow should be considered to reduce PCB temperature. Specific measures include rationally arranging components, increasing heat dissipation holes, and adopting heat pipe technology.
2. Layout design: In high-temperature PCB layout design, the principle of “thermal balance” should be followed, and components with high heat generation should be evenly distributed on the PCB to avoid concentration of heat sources. At the same time, the thermal coupling effect between components should be considered to minimize thermal interference.
3. Wiring design: In high-temperature PCB wiring design, the “short, straight, and wide” principle should be followed to shorten the wire length, reduce bending, and increase the wire width as much as possible to reduce wire resistance and temperature gradient. In addition, crossing wires and over-dense wiring should be avoided to reduce electromagnetic interference and heat dissipation problems.
4. Grounding design: In high-temperature PCB grounding design, the “single point grounding” principle should be followed to ensure the minimum grounding resistance. At the same time, a multi-layer grounding structure should be adopted to improve the grounding effect and heat dissipation performance.
5. Protection design: In the protection design of high-temperature PCB, attention should be paid to moisture-proof, dust-proof, anti-corrosion and other measures. Specific measures include adopting sealed structures and adding protective coatings.

High temperature PCB manufacturing process

1. Board preparation: Select the appropriate substrate material and thickness according to the design requirements, and perform necessary pretreatment (such as cleaning, drying, etc.).
2. Pattern transfer: Transfer the designed circuit pattern to the substrate through photolithography or laser printing. During this process, attention should be paid to the control of graphics accuracy and resolution.
3. Etching and film removal: Remove unnecessary copper layer or covering layer to form the required circuit pattern. During this process, attention should be paid to the control of etching speed and depth and the inspection of surface quality after film removal.
4. Solder mask production: Coating solder resist on the circuit pattern to protect the circuit from the external environment. During this process, attention should be paid to the uniformity and adhesion control of the solder resist.
5. Surface treatment: Surface treatment (such as gold plating, silver plating, etc.) is performed on the exposed copper surface to improve its conductivity and corrosion resistance. During this process, attention should be paid to the control of coating thickness and uniformity and the inspection of surface quality.
6. Welding and assembly: Solder the components to the PCB and perform necessary assembly work. During this process, attention should be paid to the welding quality and installation accuracy of components as well as the stability inspection of the overall structure.
7. Testing and acceptance: Test and accept the welded PCB to ensure that it meets the design requirements and performance indicators. During this process, attention should be paid to the accuracy and reliability of the test method and the reasonableness of the acceptance criteria.

Summary and suggestions

1. When selecting high-temperature PCB materials, factors such as high-temperature resistance, mechanical strength, electrical properties, and cost should be comprehensively considered to select the most suitable material type and specifications.
2. When designing high-temperature PCBs, principles such as thermal design, layout design, wiring design, grounding design, and protection design should be followed to ensure the stability and reliability of the PCB in high-temperature environments.
3. In the high-temperature PCB manufacturing process, attention should be paid to the quality control and technical requirements of board preparation, pattern transfer, etching and film removal, solder mask production, surface treatment, welding and assembly, and testing and acceptance.
4. In order to improve the heat dissipation performance and service life of high-temperature PCBs, some additional measures can be taken, such as adding auxiliary heat dissipation structures such as heat dissipation holes or heat sinks; using materials with high thermal conductivity and optimizing heat conduction paths.
5. In practical applications, it is recommended to formulate detailed high-temperature PCB design specifications and implementation plans based on specific needs and conditions, and conduct sufficient experimental verification and evaluation work to ensure the feasibility and effectiveness of the design solution.

High Temperature PCB Design Factory

Shenzhen Fumax Technology Co., Ltd. is a high-temperature PCB design factory in China, focusing on circuit board PCB assembly and design customization development, component procurement, software programming, SMT patching, DIP welding, assembly testing and painting, etc. one-stop Serve.