Sensors and Sensor Interface


Digital Thermometer with SPI/3-Wire Interface


The DS1722 Digital Thermometer and Thermostat with SPI/3-Wire Interface provides temperature readings which indicate the temperature of the device. No additional components are required; the device is truly a temperature-to-digital converter. Temperature readings are communicated from the DS1722 over a Motorola SPI interface or a standard 3-wire serial interface. The choice of interface standard is selectable by the user.

For applications that require greater temperature resolution, the user can adjust the readout resolution from 8 to 12 bits. This is particularly useful in applications where thermal runaway conditions must be detected quickly. For application flexibility, the DS1722 features a wide analog supply rail of 2.65V - 5.5V. A separate digital supply allows a range of 1.8V to 5.5V.

The DS1722 is available in an 8-pin SO (150mil) and 8-pin µMAX package.

Applications for the DS1722 include personal computers/servers/workstations, cellular telephones, office equipment, or any thermally-sensitive system.
DS1722: Functional Block Diagram DS1722: Functional Block Diagram Enlarge+

Key Features

  • Temperature Measurements Require No External Components
  • Measures Temperatures from -55°C to +120°C. Fahrenheit Equivalent is -67°F to +248°F
  • Thermometer Accuracy is ±2.0°C
  • Thermometer Resolution is Configurable from 8 to 12 bits (1.0°C to 0.0625°C Resolution)
  • Data is Read From/Written to Via a Motorola Serial Peripheral Interface (SPI) or Standard 3-Wire Serial Interface
  • Wide Analog Power Supply Range (2.65V - 5.5V)
  • Separate Digital Supply Allows for 1.8V Logic
  • Available in an 8-Pin SO (150mil) and 8-Pin µMAX package


  • Cell Phone Base Stations
  • Computer Peripherals
  • Networking
  • Telecommunications
  • Test Systems
Part Number Sensor Type Interface Accuracy
Parasite Pwr. Temp. Resolution
Oper. Temp.
See Notes
DS1722  Local 3-Wire/SPI 2 No
-55 to +125 $1.19 @1k
See All Temperature Sensors (111)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.


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