How to control Peltier Thermo-Electric Cooler?

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Hello, I’m new here and in electronic world… I would like to use “Peltier Thermo-Electric Cooler”…

How do I control it? Say if I have target temperature of 10c or 50c… Can I use PWM?

I need it for cooling the backplate of my computer graphic card that is now around 90c.

Thank you for your help.

Ferdy

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Hi Ferdy
Yes you can. It will respond to the average current which id directly proportional to the PWM duty cycle. Make sure the cold side makes good thermal contact with the card backplate or whatever you are trying to cool. I mention this as the Peltier device will have a hot and cold side. That device in the link if set up to cool something will have the heat sink on the “hot” side. These devices can be a heater just by reversing the power connections. Very handy.
Cheers Bob

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Hi Rob, thank you for your fast reply. My understanding this device will cool down pretty fast and can create condensation or frost effect - which is not ideal for electronic devices. Any suggestion how to solve this?

Can we solve that by adjusting the PWM to the correct settings (that achieve target temp 40c)?

or should I use “Temperature Controller”? Some device can turn on the Thermo Electric if temp is over 70c, then turn off when it reaches 40c… Do you think this will avoid the condensation issue? Do you think on and off action is ok for “Thermo Electric”? or it will damage it? Because the cycle will be hundred times in a day?

Thank you - Ferdy

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Hi Ferdy,

If you’re only trying to reach 40 degrees, a good enough heatsink and fan assembly would be more than enough I’d think, especially since a backplate is generally not designed with massive cooling in mind (unless you’ve got high-heat chips on the back of the board as well)

You’re welcome to pursue Peltier modules, however, keep in mind that they produce more heat than they transfer, so you’d make the internals of the PC hotter as a whole, and they introduce the issue of condensation.

-James

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Good point James. I had completely overlooked internal heat rise.
These devices should be vented to open air. This is mostly the case when they are used in thermo-electric cooler boxes etc. Always been the case when I have used them (that’s my excuse for missing this point anyway). Has to be considered. 12V@5A=60W and it has to go somewhere.
Cheers Bob

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Hey Ferdy,

You could use a Peltier module for that application, although unless you’re running some high-powered GPU with some application that is quite intensive for an extended period of time usually the inbuilt cooling can handle it. And James is exactly right, depending on the differential and humidity that the Peltier generates it could certainly create some condensation which is a serious problem when you’re running it so close to an expensive GPU.

Out of curiosity, which GPU are you running and what cooling does it currently have in place?