Thermoelectric cooler (TEC) or Peltier cooler is becoming popular because of its robustness and maintenance free characteristic. Here is one example of a linear thermoelectric cooler (TEC) driver circuit. This driver  is capable of delivering ±2A into a TEC. This circuit operates on a single +5V supply and drives the TEC in the most preferred “constant-current” mode. Here is the schematic diagram of the circuit:

thermo electric cooler driver circuit schematic

This TEC driver amplifier is a voltage-controlled current source. Constant current drive eliminates the effect of thermal “back  EMF” on current through the TEC under dynamic temperature control conditions. Constant-current drive also assures that TEC drive current is independent of production variations in TEC junctions or long-term aging. [Schematic diagram source: Burr-Brown Products Application Report]