16-Bit Single-Channel Programmable Current Output DAC for 4-20mA Current-Loop Applications

The DAC7750 and DAC8750 (DACx750) are low-cost, precision, fully-integrated, 12-bit and 16-bit digital-to-analog converters (DACs) designed to meet the requirements of industrial process-control applications. These devices can be programmed as a current output with ranges of 4 mA to 20 mA, 0 mA to 20 mA, or 0 mA to 24 mA. The DACx750 include reliability features such as CRC error checking on the SPI frame, a watchdog timer, an open circuit, compliance voltage, and thermal alarm. In addition, the output current can be monitored by accessing an internal precision resistor.

These devices include a power-on-reset function designed to power up the device in a known state (IOUT is disabled and in a Hi-Z state). The CLR pin sets the current output to the low end of the range if the output is enabled. Program the zero and gain registers to digitally calibrate the device in the end system. The output slew rate is also programmable by register. These devices can superimpose an external HART signal on the current output, and operate with a 10-V to 36-V supply.