Electronic circuits aren’t 100% efficient. For example, a power supply with a 60W input can have a 50 W output. The energy that’s lost is converted to heat and heat can degrade component life.
To manage heat in circuits, Z-AXIS and its business unit, Bear Power Supplies, use various strategies. The method we select is a function of the amount of heat to dissipate, but we also consider other factors and look for hot spots with our thermal camera.
Some electronic components, such as three terminal voltage regulators, don’t generate a lot of heat, yet they’re still large enough to radiate heat into the surrounding air. Air isn’t the best thermal conductor, however, so relying on convection and radiation alone is often insufficient.
Copper Floods and Metal Clad Circuit Boards
That’s why some circuits use large copper areas called floods for thermal management.
Metal clad circuit boards can absorb and dissipate even more heat, sometimes as much as 10 watts. Yet many electronic circuits need to move more heat than this. That’s where heat sinks come in.
Heat Sinks
Z-AXIS designs and machines these metal components from extrusions that we purchase. Whether the extrusion is standard or custom, we buy the bars, cut them to length, and debur the finished parts. We can create heat sinks from copper, but this is expensive. Aluminum costs less but still has a thermal conductivity that’s high enough for effective heat dissipation.
Knowing which aluminum alloy to choose isn’t just a mechanical engineering problem. It’s also an issue for electrical engineers. Depending on the specific alloy, thermal conductivity can change by 50% or more.
Thermal Greases and Pads
Metal heat sinks won’t wear out, but there are small gaps between them and the circuit board. Since air has a low thermal conductivity, Z-axis applies a thermal grease or thermal pad between these surfaces. Some thermal pads come pre-cut, but we can also buy sheet materials that we cut to size.
Electronic Fans
The final thermal management method, electronic fans, is the one we use the least when electronic devices need to last for many years. This is because fans wear out over time. If a device does require a fan, however, we can control the fan speed so that it lasts longer and runs quieter.
Heat is a common enemy of reliable electronics, but Z-AXIS and Bear Power Supplies use thermal management methods that remove heat before it becomes a problem. If you’re looking for a reliable PCBA partner, contact us.