DESCRIPTION

The DS1621 Digital Thermometer and Thermostat provides 9-bit temperature readings, which indicate the temperature of the device. The thermal alarm output, TOUT, is active when the temperature of the device exceeds a user-defined temperature TH. The output remains active until the temperature drops below user defined temperature TL, allowing for any hysteresis necessary.

User-defined temperature settings are stored in nonvolatile memory so parts may be programmed prior to insertion in a system. Temperature settings and temperature readings are all communicated to/from the DS1621 over a simple 2-wire serial interface.

FEATURES

■ Temperature measurements require no external components

■ Measures temperatures from -55°C to +125°C in 0.5°C increments. Fahrenheit equivalent is -67°F to 257°F in 0.9°F increments

■ Temperature is read as a 9-bit value (2-byte transfer)

■ Wide power supply range (2.7V to 5.5V)

■ Converts temperature to digital word in less than 1 second

■ Thermostatic settings are user definable and nonvolatile

■ Data is read from/written via a 2-wire serial interface (open drain I/O lines)

■ Applications include thermostatic controls, industrial systems, consumer products, thermometers, or any thermal sensitive system

■ 8-pin DIP or SO package (150mil and 208mil)