The AD596/AD597 is a monolithic temperature setpoint controller
that has been optimized for use at elevated temperatures
such as those found in oven control applications. The device
cold junction compensates and amplifies a type J or K thermocouple
input to derive an internal signal proportional to temperature.
The internal signal is then compared with an externally
applied setpoint voltage to yield a low impedance switched output
voltage. Dead-Band or switching hysteresis can be programmed
using a single external resistor. Alternately, the AD596/AD597 can
be configured to provide a voltage output (10 mV/°C) directly from
a type J or K thermocouple signal. It can also be used as a standalone
voltage output temperature sensor.
The AD596/AD597 can be powered with a single supply from
+5 V to +30 V, or dual supplies up to a total span of 36 V.
Typical quiescent supply current is 160 mA, which minimizes
self-heating errors.
The AD596/AD597 H package option includes a thermocouple
failure alarm that indicates an open thermocouple lead when
operated in the temperature proportional measurement mode.
The alarm output has a flexible format which can be used to drive relays, LEDs or TTL logic.