DAC161P997

DAC161P997 Single-Wire 16-bit DAC for 4-20mA Loops DAC161P997 August 2, 2011 Single-Wire 16-bit DAC for 4-20mA Loops 1.0 General Description The DAC161P997 is a 16- bit ∑Δ digital-to-analog converter (DAC) for transmitting an analog output current over an industry standard 4-20 mA current loop. It offers 16-bit accuracy with a low output current temperature coefficient (29ppm/°C) and excellent long-term output current drift (90 ppmFS) while consuming less than 190µA. The data link to the DAC161P997 is a Single Wire Interface (SWIF) which allows sensor data to be transferred in digital format over an isolation boundary using a single isolation component. The DAC161P997’s digital input is compatible with standard isolation transformers and optocouplers. Error detection and handshaking features within the SWIF protocol ensure error free communication across the isolation boundary. For applications where isolation is not required, the DAC161P997 interfaces directly to a microcontroller. The loop drive of the DAC161P997 interfaces to a HART (Highway Addressable Remote Transducer) modulator, allowing injection of FSK modulated digital data into the 4-20mA current loop. This combination of specifications and features makes the DAC161P997 ideal for 2- and 4-wire industrial transmitters. The DAC161P997 is available in a 16–lead LLP package and is specified over the extended industrial temperature range of -40°C to 105°C. 2.0 Applications Two-wire, 4-20 mA current loop transmitt...