AD7845SQ/883B

Overview

The AD7845SQ/883B is a 12-bit CMOS multiplying digital-to-analog converter (MDAC) with an integrated output amplifier, manufactured by Analog Devices. It operates within an extended temperature range of -55°C to +125°C and features guaranteed monotonicity across this range. The device utilizes the LC2MOS process for precision linear components on a single chip. Key electrical specifications include a maximum relative accuracy of -1 LSB at +25°C and -3/4 LSB over the full temperature range. It supports ±15 V power supplies (14.25 V to 15.75 V) and provides a voltage output capable of driving a 2 kΩ load to -10 V. The component is housed in a hermetic Q-24 Cerdip package.

Feature Summary

• Complete 12-bit 4-quadrant multiplying DAC with on-chip output amplifier
• Guaranteed monotonic operation from TMIN to TMAX (-55°C to +125°C)
• Integrated application resistors (RA, RB, RC) for gain ranging and offset adjustment
• TTL and 5 V CMOS compatible digital inputs with simple microprocessor interfacing

Applications

• Automatic Test Equipment
• Digital Attenuators
• Programmable Power Supplies
• Programmable Gain Amplifiers
• Digital-to-4–20 mA Converters

Procurement Notes

Verify that the ordering suffix /883B confirms MIL-STD-883, Class B processing requirements are met. Confirm the package type is the hermetic Q-24 Cerdip variant suitable for the specified extended temperature range. Ensure supply chain documentation aligns with military or aerospace qualification standards if required by the system design.

Selection Notes

Select the AD7845SQ/883B when extended temperature operation (-55°C to +125°C) and hermetic packaging are mandatory. This model provides -1 LSB relative accuracy at +25°C. For applications requiring tighter accuracy (±1/2 LSB), consider the AD7845TQ/883B. Ensure the design accommodates the ±15 V supply rails and 2 kΩ minimum load resistance constraints defined in the specifications.

Part Context

The AD7845 series represents the industry's first 4-quadrant multiplying DAC with an on-chip amplifier. The SQ/883B variant specifically denotes the S-grade performance level packaged in a hermetic ceramic DIP format processed to military standards. It belongs to the broader AD7845 family which includes commercial (J/K), industrial (A/B), and extended temperature (S/T) versions in various packages including SOIC, PLCC, and LCC.

Replacement Considerations

The AD7845TQ/883B is a direct functional substitute offering improved relative accuracy (±1/2 LSB) while maintaining the same package, pinout, and extended temperature range.