AD596

a FEATURES Low Cost Operates with Type J (AD596) or Type K (AD597) Thermocouples Built-In Ice Point Compensation Temperature Proportional Operation – 10 mV/؇ C Temperature Setpoint Operation – ON/OFF Programmable Switching Hysteresis High Impedance Differential Input Thermocouple Conditioner and Setpoint Controller AD596*/AD597* FUNCTIONAL BLOCK DIAGRAM TO-100 –ALM –IN +ALM +IN ICE POINT COMP – G + – G + + +A V+ GENERAL DESCRIPTION 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 µA, which minimizes self-heating errors. The AD596/AD597 H package option includes a thermocouple failure alarm that indicates an open thermocouple lead when operate...