A High Efficiency TEC Controller Solution

The ADN88311 is a monolithic TEC controller. It has two integrated, zero drift, rail-to-rail comparators, and a PWM driver. A unique PWM driver works with an analog driver to control external selected MOSFETs in an H-bridge. By sensing the thermal detector feedback from the TEC, the ADN8831 can drive a TEC to settle the programmable temperature of a laser diode or a passive component attached to the TEC module.

The ADN8831 supports NTC thermistors or positive temperature coefficient (PTC) RTDs. The target temperature is set as an analog voltage input either from a DAC or from an external resistor divider driven by a reference voltage source.

A proportional integral differential (PID) compensation network helps to quickly and accurately stabilize the ADN8831 thermal control loop. An adjustable PID compensation network example is described in the AN-695 Application Note, Using the ADN8831TEC Controller Evaluation Board. A typical reference voltage of 2.5 V is available from the ADN8831 for thermistor temperature sensing or for TEC voltage/current measuring and limiting in both cooling and heating modes.

Applications

* Thermoelectric cooler (TEC) temperature control

* DWDM optical transceiver modules

* Optical fiber amplifiers

* Optical networking systems

* Instruments requiring TEC temperature control

1 Product is covered by U.S. Patent No. 6,486,643

* Two integrated zero drift, rail-to-rail, chop amplifiers

* TEC voltage and current operation monitoring

* Programmable TEC maximum voltage and current

* Programmable TEC current heating and cooling limits

* Configurable PWM switching frequency up to 1 MHz

* Power efficiency: > 90%

* Temperature lock indication