Design Consideration When Selecting High-Temperature PCBs

Printed circuit boards (PCBs) may fail to function due to several reasons. Among these reasons, heat dissipation has always been a factor. As the demand for compact PCBs increases, power density becomes an issue which raises the temperature thus damaging the electronic component. This issue can be solved using high-temperature PCBs. High-temperature PCBs are gaining immense popularity due to higher glass transition temperature (Tg) more than 150 degrees Celsius. To keep up with the demand for high-power density applications, it is important to understand high-temperature PCB design considerations. This post focuses on factors required for high-temperature PCB manufacturing. So, stay tuned.

A Quick Overview of High-Temperature PCB Design Consideration

As the name implies, high-temperature PCBs can withstand high temperatures. They are popularly known as High-Tg PCBs with a temperature range varying from 150 to 170 degrees Celsius. When manufacturing these PCBs, it is important to consider a few factors. The following are some important ones.

  • Materials: Material consideration is one of the important aspects when manufacturing high-temperature PCBs. The material selection depends on a simple thumb rule. For instance, if the operating temperature requirements are up to or above 130 degrees Celsius, then the circuit board must be manufactured using high Tg materials. High-temperature PCB materials must be chosen by considering flame and chemical resistance as well as low smoke and ash formation. Glass-epoxy laminate or FR4 is one of the most widely used materials for a high-temperature PCB assembly. The material can withstand temperatures ranging between 90 and 110 degrees Celsius. FR4 offers electrical resistance in dry as well as wet conditions. Thus, the heat dissipation due to conductors and dielectrics in resisted in these materials. Polyamide is another popular material that withstands a temperature range between 130 and 260-degree Celsius.
  • Component Design: Most of the PCB components can’t function well due to extreme temperature. For instance, silicon chips may not function as expected in high-temperature environments, creating a worthless circuit board. Therefore, if the circuit board design demands components like a microcontroller or logic chips, it is important to set a temperature parameter. Once the component has been successfully picked up, the right placement is the next stage. Every heat-creating component should be placed as far as possible to avoid excess heat generation within the environment. Enclosures should be considered after the placement of the components. Each circuit board must have enclosures that insulate against heat. Some considerations are thermal insulation on the inner walls of temperature shielding using materials such as Kevlar or in some cases ABS plastic or titanium.
  • Ventilation: Ventilation is a vital aspect of high-temperature PCB design. This is because multiple heat-generating components are placed in the circuit board design. A small case fan may be placed as an intake fan in combination with a heat sink. Next, one must look at the fan placement, which will be dependent on the placement of heat sink blades.

The above guidelines help electronics manufacturers to create superior, performance-driven high-temperature PCBs that can withstand high-temperature environments. Are you looking for high-quality high-temperature PCBs for your next electronic applications? If yes, you must employ an industry player who will assist you throughout the process. With vast years of market presence and highly experienced employees, Rigiflex Technology specializes in designing and manufacturing high-temperature PCBs. Their team of experts work closely to understand your thermal requirements.