Digital Thermometer Integrates Two Separate Power Supplies

Touted as the first digital thermometer to support two separate power supplies and a choice of software-selectable communications interfaces--i.e., 3-wire and SPI--the DS1722 chip meets the need for multiple voltage capability in portable, mixed-signal systems. One of the chip’s pins accepts an analog power supply over the 2.65V to 5.5V range and a separate pin accepts power over the 1.8V to 5.5V range. The added choice of standard 3-wire and SPI serial interfaces gives designers the flexibility to match different networking communication protocols in embedded systems. Any heat-sensitive device that handles both analog and digital signals can benefit from the device. The chip’s direct-to-digital technology provides temperature readings accurate to 2.0°C over a range from -40°C to 85°C without additional components.