General Description:

The TCN75 is a serially programmable temperature sensor that notifies the host controller when ambient temperature exceeds a user programmed set point. Hysteresis is also programmable. The INT/CMPTR output is programmable as either a simple comparator for thermostat operation or as a temperature event interrupt. Communication with the TCN75 is accomplished via a two-wire bus that is compatible with industry standard protocols. This permits reading the current temperature, programming the set point and hysteresis, and configuring the device.

The TCN75 powers up in Comparator mode with a default set point of 80°C with 5°C hysteresis. Defaults allow independent operation as a stand-alone thermostat. A shutdown command may be sent via the 2-wire bus to activate the low-power Standby mode. Address selection inputs allow up to eight TCN75s to share the same 2-wire bus for multizone monitoring.

All registers can be read by the host and the INT/CMPTR output’s polarity is user programmable. Both polled and interrupt driven systems are easily accommodated. Small physical size, low installed cost, and ease-of-use make the TCN75 an ideal choice for implementing sophisticated system management schemes.

Features:

• Solid-State Temperature Sensing:

0.5°C Accuracy (Typ.)

• Operates from -55°C to +125°C

• Operating Supply Range: 2.7V to 5.5V

• Programmable Trip Point and Hysteresis with

Power-up Defaults

• Standard 2-Wire Serial Interface

• Thermal Event Alarm Output Functions as

Interrupt or Comparator/Thermostat Output

• Up to 8 TCN75s may Share the Same Bus

• Shutdown Mode for Low Standby Power Consumption

• 5V Tolerant I/O at VDD = 3V

• Low Power:

- 250 μA (Typ.) Operating

- 1 μA (Typ.) Shutdown Mode

• 8-Pin SOIC and MSOP Packaging

Applications:

• Thermal Protection for High-Performance CPUs

• Solid-State Thermometer

• Fire/Heat Alarms

• Thermal Management in Electronic Systems:

- Computers

- Telecom Racks

- Power Supplies/UPS/Amplifiers

• Copiers/Office Electronics

• Consumer Electronics

• Process Control