AD7937BR-REEL

Overview

The AD7937BR-REEL is a dual 12-bit current-output digital-to-analog converter (DAC) manufactured by Analog Devices Inc. in a 24-lead Small Outline Integrated Circuit (SOIC) package. 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 with ±10% tolerance and supports TTL, 74HC, and 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 to 0.01%, and an output leakage current of 10 nA max. The architecture utilizes a byte-loading structure with separate analog ground pins for each DAC.

Feature Summary

• Dual 12-bit DACs integrated on one monolithic chip for excellent thermal tracking and 0.5% typical matching.
• Separate AGND pins (AGNDA and AGNDB) allow independent biasing and increased application versatility.
• Byte-loading structure compatible with 8-bit microprocessors, supporting right-justified data formats.
• Asynchronous CLR line enables clearing all registers for calibration routines.

Applications

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

Procurement Notes

Verify that the component matches the specific B grade requirements, which guarantees a relative accuracy of ±1/2 LSB and a maximum gain error of 3 LSB over the industrial temperature range. Confirm the package type is the 24-lead SOIC (R-24). Ensure handling procedures account for ESD sensitivity, as the device is susceptible to damage from high-energy electrostatic discharges despite internal protection circuitry.

Selection Notes

Select the AD7937BR variant when strict accuracy limits are required, specifically a gain error no greater than 3 LSB compared to the 6 LSB limit of the A version. The device requires external operational amplifiers to convert current outputs to voltage; ensure selected op-amps meet bandwidth and offset voltage specifications to maintain linearity. Verify that the system interface can support the required setup and hold times for the byte-loading sequence.

Part Context

The AD7937 belongs to the family of LC2MOS dual DACs from Analog Devices. It is designed to save board space compared to using discrete components while maintaining performance through monolithic construction. The BR suffix indicates the commercial/industrial grade with tighter gain error specifications than the AR variant. The -REEL suffix denotes tape and reel packaging for automated assembly.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.