DAC with Integrated Buck/Boost for Industrial Automation

Texas Instruments (TI) today introduced a digital-to-analog converter (DAC) that combines industry-leading precision performance with simpler power-supply design. The 16-bit DAC8775 operates from a single, wide 12- to 36-V power rail, leveraging an integrated buck/boost converter to generate all of the required internal power supplies to save designers time, cost and significant board space.

The four-channel DAC8775 addresses the trend in factory automation and process control equipment toward input/output (I/O) modules that must squeeze more channels into a smaller space. Engineers designing these systems face the challenge of managing power dissipation in a small form factor.

By combining a 4-20mA current and voltage driver with a precision reference and a buck/boost converter, the DAC8775 enables a total system footprint that is up to 25 percent smaller than the nearest competing device. Key features and benefits of the DAC8775 data converter include:

More reliable system design: The DAC8775's on-chip diagnostic features include smart alarms that monitor open load, short circuit, over-temperature, cyclic redundancy check (CRC), watchdog timer and compliance voltage. Designers can choose preset actions that help detect faults early to facilitate reliable system operation.

Efficiency with fast response times: The device has an innovative auto-learn feature that calculates the load impedance on the 4-20mA loop and clamps the power supply. This enables faster settling time, balancing efficiency with quicker system response.

High dc performance: A total unadjusted error of 0.1 percent full-scale range (FSR) over an extended industrial temperature range of -40 to 125 degrees C enables designers to rate their output modules for higher temperature ranges. The DAC8775's high dc performance reduces the need for system calibration, saving manufacturing costs compared to a discrete solution.

Thermally optimized design: The DAC8775 dynamically adjusts the generated supply based on the current load on the 4-20mA loop. This creates an efficient system with well-controlled thermal performance, allowing more channels in a smaller space.

The DAC8775 is available now through the TI store and authorized distributors. The device comes in a 10-mm-by-10-mm quad-flat no-lead (QFN) package and is priced at US$15.72 in 1,000-unit quantities.