AD7845TQ/883B

Overview

The AD7845TQ/883B is a complete 12-bit CMOS multiplying digital-to-analog converter (MDAC) with an integrated output amplifier, fabricated on the LC2MOS process. It features full 4-quadrant multiplication capability and includes three on-chip application resistors for gain ranging and offset adjustment. The device operates within an extended temperature range of -55°C to +125°C and meets MIL-STD-883, Class B processing requirements. It utilizes a parallel interface compatible with TTL and 5 V CMOS logic, housed in a hermetic Q-24 Cerdip package.

Feature Summary

• 12-bit resolution with guaranteed monotonicity over the full operating temperature range (-55°C to +125°C).
• Integrated output amplifier capable of sourcing/sinking current into loads as low as 2 kΩ.
• On-chip application resistors (RA, RB, RC) facilitate easy gain ranging and voltage offsetting.
• MIL-STD-883, Class B processed hermetic ceramic package for high-reliability applications.

Applications

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

Procurement Notes

Verify that the component is sourced from authorized channels to ensure authenticity, particularly given the military-grade /883B designation. Confirm the presence of the metal lid connected to Pin 12 (DGND) for proper grounding. Check for ESD sensitivity markings and handle according to standard electrostatic discharge precautions during installation.

Selection Notes

Select the AD7845TQ/883B when extended temperature operation (-55°C to +125°C) and high reliability are required. The 'T' suffix indicates the tighter relative accuracy grade (-1/2 LSB max at +25°C) compared to the 'S' version. Ensure the power supply rails are within the ±14.25 V to ±15.75 V range for optimal performance.

Part Context

This part belongs to the AD7845 family of 12-bit multiplying DACs. The TQ variant specifically denotes the higher accuracy grade ('T') housed in a 24-lead Cerdip package ('Q'). The '/883B' suffix confirms compliance with MIL-STD-883, Class B standards, distinguishing it from commercial or industrial grade equivalents like the AD7845JRZ.

Replacement Considerations

The AD7845SQ/883B is a direct functional substitute with identical pinout and specifications, differing only in the accuracy grade ('S' vs 'T'). Other family members such as the AD7845ARZ or AD7845BRZ offer similar functionality but lack the hermetic packaging and military processing required for this specific part number.