Question

This is just a general question for a design project I’m working on, and I was wondering if I could get a few pointers.

Scenario: I’m trying to construct a current limiting/driver circuit that will turn on/off a 12V DC supply when a certain temperature is achieved. A thermistor is being used to read the ambient temperature, and thus the current must be increased/decreased as the thermistor’s temperature reading (resistance) strays farther from the desired temperature. The goal for now is to design a cooler that goes from room temperature (25 degrees Celsius) to around 2 degrees Celsius. The cooler itself is a Peltier TEC that operates at 12V with an internal resistance of 2 ohms.

I understand how to construct a driver circuit that will simply turn the supply on/off, but I need a variable driver that will decrease/increase the current to the cooler, depending the temperature difference.

Any pointers would be appreciated, and if there’s a forums page on Chegg that I’m unaware of, directing me to that would also be appreciated. Thanks!

Answer 1