The computer hardware industry has reduced this problem using cooling fans. The life of the electrical connections, components, and the board itself will be shortened when the device runs at extreme temperatures. Components arranged on a PCB Thicker Boards Always be mindful of component placement as it can have a major impact on your manufacturing budget. It may even be preferable to separate the components among different boards, as long as the form factor of the device can accommodate this. Multiple high power PCB components should be distributed throughout the board rather than clustered in a single location. But if the component is mounted in the middle of the board, heat can diffuse throughout the board, and the temperature of the board will be lower. If a component is mounted near the edge of the board, the heat it generates will accumulate and the local temperature can be very high. This is especially true for semiconductor components that use a PowerPAD style package. It is a good idea to mount these components near the center of the board when laying out your printed circuit board design. High current electronic components like microcontrollers can generate a significant amount of heat. Infrared view of an electronic device running at high current Placing High Power Components Ideally, the thermal landing should be located in a portion of the board that is not a point of failure. The thermal vias transport heat to the thermal landing. After thermal vias transport heat away from the hottest spots on the board itself, it must go somewhere else to maintain heat dissipation from hot spots on top of the board. Heat is transferred to a thermal via by simple conduction, and the thermal via allows heat to move away from the critical electronic components.Ī thermal landing is basically a metal plate mounted on the bottom of the board. A thermal via is a good conductor of heat that runs between the top and bottom of the board. But heat can be transferred away from the critical electrical components in the board using thermal vias. Heat cannot be efficiently exchanged with stagnant air around a hot device. Of course, this will likely require the use of a thicker board, which can be desirable in high current devices. This will also help dissipate heat into the board itself and into any nearby thermal vias.
To keep from losing usable area, the PCB trace can be placed deeper into the board. Using a large amount of copper will require that the trace width on the PCB be increased. Circuits operating at over 10 amps should go as high as 3 or 4 oz.
#Loopcad overheated areas software#
When using free pcb software and integrating fans or heat sinks is not possible, a PCB with high current density should use at least double this amount of copper. The amount of copper used in most PCBs is equivalent to about 1 oz. Electrical connections with a larger cross-sectional area have lower resistance, which reduces the amount of power lost to heat. The resistance of copper traces and vias account for significant power loss and heat generation in PCB-based devices, especially when they carry high current density. Heavier Copper for Higher Currents: PCB Design Tips Read on for some high current PCB design tips. But in some PCB devices, especially devices with small form factor, incorporating a fan or a bulky heat sink may not be possible on the ground plane. These systems essentially move heat from the board and exchange it with moving air. Everyone is probably familiar with fans and heat sinks used on computer processors. Heat that is generated by power loss in high current circuits should be moved away from the device in order to combat temperature rise. Designers will need to implement creative strategies to manage heat generated in a high current PCB layout. Power systems with high output, such as Li+ ion batteries used in electric vehicles, require integrated power management systems that are built on PCBs. This is especially true in printed circuit boards (PCBs) that operate at high current-carrying capacity. Very simply, I did not take into account the high current PCB layout.Īs electronics continue to be miniaturized, the thermal demands in these systems increase as more features are packed into smaller devices. Why did this happen you ask? No, this was not due to a short circuit. Thankfully, the destruction was minor and most of the components were salvageable. It started with the resistors and quickly spread to a nearby decoupling capacitor. I remember the first (and hopefully the only) time one of my circuits caught on fire.