DS1722

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The DS1722 can communicate using either a Motorola Serial Peripheral Interface (SPI) or standard 3-

wire interface. The user can select either communication standard through the SERMODE pin, tying it to

respectively). The analog supply powers the device for operation while the digital supply provides the

top rails for the digital inputs and outputs. The DS1722 was designed to be 1.8V Logic-Ready.

DS1722 FUNCTIONAL BLOCK DIAGRAM Figure 1

OPERATION-Measuring Temperature

The core of DS1722 functionality is its direct-to-digital temperature sensor.

The DS1722 measures

temperature through the use of an on-chip temperature measurement technique with an operating range

from -55

°=to +120°C. The device powers up in a power-conserving shutdown mode. After power-up, the

DS1722 may be placed in a continuous conversion mode or in a one-shot conversion mode. In the

continuous conversion mode, the device continuously computes the temperature and stores the most

recent result in the temperature register at addresses 01h (LSB) and 02h (MSB).

In the one-shot

conversion mode, the DS1722 performs one temperature conversion and then returns to the shutdown

mode, storing temperature in the temperature register. Details on how to change the setting after power-

up are contained in the “OPERATION-Programming” section.