AD7937BRZ

Overview

The AD7937BRZ is a dual 12-bit current-output digital-to-analog converter (DAC) manufactured by Analog Devices Inc. It integrates two monolithic DACs on a single chip, ensuring precise thermal tracking and inherent matching with a typical tolerance of 0.5%. The device operates on a nominal 5 V power supply (4.5 V to 5.5 V range) and features separate reference inputs for each channel. It utilizes an LC2MOS process and accepts TTL or 5 V CMOS logic levels. Key electrical specifications include a maximum gain error of ±3 LSB for the B version, a settling time of 1 µs max, and a digital-to-analog glitch impulse of 2.5 nV-s typical. The unit is housed in a 24-lead Small Outline Integrated Circuit (SOIC) package.

Feature Summary

• Dual 12-bit current output DACs with 0.5% ladder resistance matching
• Separate AGND pins for independent analog ground referencing
• Double-buffered data inputs allowing simultaneous update of both DACs
• Asynchronous CLR line for clearing all registers during calibration

Applications

• Automatic Test Equipment
• Programmable Filters
• Audio Applications
• Synchro Applications
• Process Control

Procurement Notes

Verify that the component matches the specific accuracy grade required for the application. The 'B' suffix indicates a tighter gain error specification compared to the 'A' variant. Confirm the package type is the 24-lead SOIC (R-24). Ensure electrostatic discharge precautions are observed during handling due to the sensitivity of the MOS gate inputs.

Selection Notes

Select the AD7937BRZ when high channel-to-channel matching and thermal tracking are critical, as the monolithic construction minimizes drift differences between channels. Choose this model over discrete solutions to save board space and simplify layout. Verify that the system can accommodate the byte-loading structure, which requires writing the lower 8 bits followed by the upper 4 bits before triggering an update.

Part Context

The AD7937 belongs to a family of dual DACs designed for applications requiring synchronized outputs from a single control source. The BRZ designation identifies the specific accuracy grade and lead-free packaging within the 24-lead SOIC form factor. This part is distinct from single-channel DACs or higher-resolution multi-channel devices, focusing specifically on the balance of performance and integration for dual-channel needs.

Replacement Considerations

The AD7937AR is a compatible alternative offering the same pinout and functionality but with a relaxed gain error specification of ±6 LSB instead of ±3 LSB.