Single-Wire 16-bit DAC from National Semiconductor

National Semiconductor Corp.

The DAC161P997 from National Semiconductor Corp., Santa Clara, CA, is a 16-bit delta-sigma DAC with a single-wire interface and 4–20 mA current-loop drive that simplifies the design of smart transmitters used in industrial 2-wire sensor systems. Temperature coefficient is 29 ppm, long-term output current drift is 90 ppm, supply current is <190 µA, and operating temperature range is –40°C to 125°C. The loop drive interfaces to a HART modulator, allowing injection of FSK-modulated digital data into the 4–20 mA current loop. Features include user-programmable start-up conditions and data-rate auto-detect as well as error detection and reporting.