AD7837AQ

Overview

The AD7837AQ is a dual 12-bit multiplying digital-to-analog converter (MDAC) featuring integrated output amplifiers. It utilizes an R-2R segmented architecture with parallel loading structure for microprocessor interfacing. The device operates on ±14.25 V to ±15.75 V supplies and supports reference inputs up to ±10 V. Key electrical specifications include a maximum settling time of 5 µs, unity gain small-signal bandwidth of 750 kHz, and full power bandwidth of 175 kHz. Relative accuracy is specified at ±1 LSB, with differential nonlinearity guaranteed monotonic at ±1 LSB. The component is housed in a 24-lead ceramic dual in-line package (CDIP).

Feature Summary

• Dual 12-bit MDACs with integrated buffered output amplifiers.
• Parallel input loading structure compatible with 8-bit microprocessors.
• High-speed performance: 5 µs max settling time and 750 kHz bandwidth.
• ±1 LSB relative accuracy and guaranteed monotonicity.

Applications

• Automatic test equipment requiring precise voltage generation.
• Function generation and waveform reconstruction systems.
• Programmable power supplies utilizing 4-quadrant multiplication.
• Synchro applications involving analog signal processing.

Procurement Notes

Verify the specific suffix 'Q' corresponds to the 24-lead Cerdip package configuration required for the design. Confirm that the A-version accuracy grade (±1 LSB) meets the system linearity requirements. Ensure the operating environment remains within the -40°C to +85°C industrial temperature range. Check for ESD sensitivity precautions during handling and assembly processes.

Selection Notes

Select this model when a parallel interface with address lines A0/A1 is preferred over serial or independent chip select architectures. The AD7837 series requires external connection of the feedback resistor RFBA/RFBB to VOUT, unlike the internally compensated AD7847. Verify that the application can accommodate the ±15 V supply rails and that the 24-lead CDIP footprint fits the PCB layout constraints.

Part Context

The AD7837 belongs to the Analog Devices LC MOS complete dual DAC family. It shares pin compatibility and functional logic with the AD7847, though the AD7847 features separate chip selects and internal feedback resistors. The AQ variant specifically denotes the commercial temperature range (-40°C to +85°C) and the ceramic DIP packaging option within the broader AD7837 product line.

Replacement Considerations

The AD7837BQ offers improved relative accuracy of ±1/2 LSB while maintaining identical pinout and functionality. For designs requiring internal feedback resistors and independent chip selects, the AD7847AQ serves as a functional alternative with modified control logic.