Power control circuit for improved power application and temperature control of thermoelectric coolers

摘要

A power control circuit for improved temperature control of thermoelectric devices to maintain the temperature of thermoelectric devices at a set point. The circuit includes an electrical power source; a rectifying device to provide rectified alternating current from the electrical power source; a comparator device; circuitry for providing a predetermined voltage to the inverting input of the comparator device derived from the rectified alternating current; a sensor device to monitor the temperature associated with the thermoelectric device; circuitry for providing an adjustable DC voltage to the non-inverting input of the comparator; a programmable control device to receive an output from the sensor device and provide an output to the circuitry for providing an adjustable DC voltage; a switching device connected between the thermoelectric device and the rectified alternating current; and control circuitry which is coupled between the switching device and the output of the comparator device and is controlled by the output of the comparator device, the control circuitry activates and deactivates the switching device to apply power to the thermoelectric device when the operating temperature of the thermoelectric device is different than the set point temperature to maintain the thermoelectric device at the set point temperature with minimum variations therefrom. A push-pull transistor configuration is used with the "pulse positioning" power supply allowing bi-polar control of thermoelectric device assemblies.