ADN8831

The ADN8831 is a monolithic controller that drives a Thermoelectric Cooler (TEC) to stabilize the temperature of a laser diode or a passive component used in telecommunications equipment. This device relies on a Negative Temperature Coefficient (NTC) thermistor or a positive temperature coefficient RTD device to sense the temperature of the object attached to the TEC. The target temperature is set with an analog input voltage either from a DAC or with an external resistor divider.

The loop is stabilized by a PID compensation amplifier with high stability and low noise. The compensation network can be adjusted by the user to optimize temperature settling time. The component values for this network can be calculated based on the thermal transfer function of the laser diode or obtained from the look-up table given in the applications notes. Voltage outputs are provided to monitor both the temperature of the object and the voltage across the TEC. A 2.5V voltage  reference is provided for the thermistor temperature sensing  bridge. An external sense resistor provides true current sensing. Current limits for both heating and cooling can be set  independently.