Embedded debut: Integrated precision digital-to-analog converters

Norwood, MA—Analog Devices Inc. has introduced new precision digital-to-analog converters (DACs) that improve the reliability of industrial process control applications in harsh factory environments, including those operating under extreme temperatures or high compliance voltages. Suitable for factory process control, distributed control, and smart transmitter systems, they reduce board space up to 70%, enabling system design engineers to deliver more cost- and space-efficient industrial equipment
By Control Engineering Staff October 16, 2007

Norwood, MA

Analog Devices Inc

. has introduced new precision digital-to-analog converters (DACs) that improve the reliability of industrial process control applications in harsh factory environments, including those operating under extreme temperatures or high compliance voltages.

Four 12-bit to 16-bit single-channel DACs

integrate user-programmable current source and voltage output. They are suitable for factory process control, distributed control, and smart transmitter systems. Eliminating the need for bulky discrete analog circuitry and mechanical pin-strapped configurations, the DACs reduce board space up to 70%, enabling system design engineers to deliver more cost- and space-efficient industrial equipment.

“Our newest DACs provide a compact and intelligently integrated solution for 4-20 mA transmitters and analog I/O systems, meeting the growing demand for feature-rich, highly reliable programmable automation controllers,” said Mike Britchfield, product line director, Precision Data Converters, Analog Devices. “These devices offer industrial designers a high-performance, 16-bit control system that provides excellent drift and stability specifications, while reducing system inaccuracies and cost by eliminating multi-temperature factory calibration sequences.”

The new products, the AD5422, AD5420, AD5412, and AD5410, leverage technological advancements enabled by the company’s iCMOSTM industrial process technology, to achieve the high voltages needed by industrial applications. The AD5422 single-channel 16-bit DAC operates from a single 12-V to 48-V supply, or dual +/-12 V to +/-24 V supplies. The output configuration is software selectable from options of 5 V, 10 V, +/-5 V and +/-10 V in voltage mode and 4-20 mA, 0-20 mA, and 0-24 mA in current mode.

The AD5422 achieves an accuracy level of 0.1 percent TUE (total unadjusted error) while operating in voltage or current mode and includes a precision 5-ppm / deg C internal reference. Internal fault detection circuitry provides hardware and software indication of line faults. The device integrates an over-temperature indicator. To sense output voltage, it includes a buffered voltage output with force and sense capability that can compensate for series protection resistors and field-wiring resistance. The on-chip programmable precision output amplifier allows rail-to-rail output swing, maximizing dynamic range.

The AD5412 is a pin-compatible single-channel 12-bit current source and voltage output DAC. The AD5420 (16-bit) and AD5410 (12-bit) operate in current source mode only. With a single 12 V to 60 V supply, their output configuration is software selectable from 4-20 mA, 0-20 mA and 0-24 mA options.

The DACs incorporate a 30-MHz serial peripheral interface (SPI), power-on reset and hardware CLR and CLR-select functionality for output control. All are housed in 24-lead TSSOP (thin-shrink small-outline) and 40-lead LFCSP (lead-frame chip-scale) packages. Sample units are available.

Control Engineering News Desk
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