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I am considering a project that involves the following part.

https://www.amazon.com/Dilwe-Thermoelectric-TEC104901-Semiconductor-Heatsink/dp/B08YFBZW64/ref=sr_1_16?crid=DYBHWMJ9VUJN&keywords=5+volt+peltier+module&qid=1660139139&sprefix=5+peltier+module%2Caps%2C86&sr=8-16 However I need to know if hooking it up to a raspberry pi's gpio will overload the pi. The link says that the product uses 5 volts and 1 amp. I am considering using either a pi pico or a zero for this.

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  • don't use the Raspberry Pi as a power supply ... doing so, can turn the RPi into an expensive fuse
    – jsotola
    Aug 10, 2022 at 23:33
  • there is a difference between powering something and controlling something
    – jsotola
    Aug 10, 2022 at 23:34
  • SP1848-27145 4.8V Seebeck Thermoelectric Power Generator TEG Peltier Module Aug 11, 2022 at 14:07

3 Answers 3

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Welcome, I doubt it unless you have a super USB. My reasoning is the specification for USB states a USB 3.0, can provide a maximum of 900mA or translated 0.9 Amp. These power output specifications are a rated based on a standard output. The USB 3.0 dedicated charging and charging downstream ports provide up to 1,500 mA or 1.5A. which is pushing what you will need to the max. The best solution is to power the load (cooler) with an external power supply, your pi will love you for doing that. You can turn it on and off with a solid state relay if you like. It depends on which solid state relay you use, you may not have to connect the grounds.

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The Pi's GPIO can only supply of the order of 20 milliamps and are 3V3. The Pico will be similar.

Perhaps you mean the Pi's 5V rail (pins 2 and 4 of the expansion header). They should be able to supply an amp but they are not switchable.

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If you just want to hook it up to power, then you would connect it to 5v and GND pins. The 5v power rail can draw up to the current that the power supply can provide. You'll also have to budget around 500mA of that for the Raspberry Pi itself, so you'll want at least a 1.5A (2A would be better) usb power supply if you want to hook up the peltier module you mentioned (1A draw).

If you also want to be able to switch the peltier on/off, then you'll want to control the switching through an N-Channel MOSFET - that can be switched safely using the GPIO while the main power for the Peltier comes from the 5v power rail.

As a side note - the 3.3v rail cannot source nearly as much power - it is limited by what the 3.3v regulator can provide (there's no definitive answer on this that I've found, but I've found this:

"The Raspberry Pi 3.3V supply was designed with a maximum current of ~3mA per GPIO pin. If you load each pin with 16mA, the total current is 272mA. The 3.3V supply will collapse under that level of load."

from https://www.raspberrypi.com/documentation/computers/raspberry-pi.html

So the 3.3v rail cannot be used for any appreciable power. 5v rail feeds off the USB input, so it is whatever the USB power supply can provide (minus the needs of the Raspberry Pi itself).

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