Well established in the field for some time, the 5R9-350 open-board temperature controller is specifically designed with a proportional integral control algorithm to provide precise control to thermoelectric (Peltier effect) modules at the most economical price. The controller can be set up for heat or cool and can run Ramp & Soak profile. Pulse width modulation (PWM) controls the power level in the thermoelectric module at a base frequency of 2.5 KHz. Datasheet: http://www.ovenind.com/pdf/datasheets/DS-5R9-350.pdf
Low Cost Temperature Controller Operates With Peltier Effect Modules
Oven Industries Inc.