Industrial Current Out Driver, Single-Supply, 55 V Maximum Supply, Programmable Ranges

The AD5749 is a single channel, low cost, precision, current output driver with hardware or software programmable output ranges. The software ranges are configured via an SPI-/MICROWIRE™- compatible serial interface. The AD5749 targets applications in PLC and industrial process control. The analog input to the AD5749 is provided from a low voltage, single-supply digital-to- analog converter (DAC) and is internally conditioned to provide the desired output current/voltage range.

The output current range is programmable across two current ranges: 0 mA to 24 mA, or 4 mA to 20 mA. Current output is open-circuit protected and can drive inductive loads of 0.1 H. The device is specified to operate with a power supply range from 10.8 V to 55 V. Output loop compliance is 0 V to AVDD − 2.75 V.

The flexible serial interface is SPI and MICROWIRE compatible and can be operated in 3-wire mode to minimize the digital isolation required in isolated applications. The interface also features an optional PEC error checking feature using CRC-8 error checking, useful in industrial environments where data communication corruption can occur.

The device also includes a power-on reset function ensuring that the device powers up in a known state and an asynchronous CLEAR pin that sets the outputs to the low end of the selected current range.

An HW SELECT pin is used to configure the part for hardware or software mode on power-up.

Applications

* Process control

* Actuator control

* PLCs

* Current output ranges: 0 mA to 24 mA or 4 mA to 20 mA

* ±0.03% FSR typical total unadjusted error (TUE)

* ±5 ppm/°C typical output drift

* 2% overrange

* Flexible serial digital interface

* On-chip output fault detection