AD7847BRZ

Overview

The AD7847BRZ is a dual 12-bit monolithic digital-to-analog converter (DAC) manufactured by Analog Devices Inc. It features two independent DAC channels with integrated buffered output amplifiers, eliminating the need for external feedback resistors. The device operates on dual power supplies ranging from ±14.25 V to ±15.75 V and supports an industrial temperature range of -40°C to +85°C. Key electrical specifications include a maximum relative accuracy of ±1/2 LSB, a typical voltage output settling time of 3 µs to within ±1/2 LSB, and a unity gain small-signal bandwidth of 750 kHz. Data is loaded via a parallel interface using separate chip select inputs (CSA, CSB) and a common write input (WR).

Feature Summary

• Dual 12-bit resolution with integrated buffered output amplifiers.
• High precision: ±1/2 LSB relative accuracy and ±1 LSB DNL guaranteed monotonicity.
• Fast settling time of 3 µs typ and 750 kHz unity gain bandwidth.
• Parallel interface with independent channel selection via CSA and CSB pins.

Applications

• Programmable Gain Amplifiers (PGA) utilizing internal feedback resistance.
• Analog panning circuits for audio signal distribution.
• Four-quadrant multiplication and bipolar operation systems.

Procurement Notes

Verify the specific suffix 'BRZ' corresponds to the SOIC-24 package and industrial temperature grade (-40°C to +85°C) as defined in the ordering guide. Confirm that the 'Z' suffix indicates RoHS compliance. Ensure the source documentation explicitly links this part number to the AD7847 specifications provided in the datasheet.

Selection Notes

Select the AD7847BRZ when dual independent 12-bit DACs with internal buffering are required. Unlike the AD7837, this model uses separate chip selects for each channel rather than address lines, simplifying parallel microprocessor interfacing. It is suitable for applications requiring simultaneous or independent channel updates with high linearity and low glitch impulse.

Part Context

The AD7847 is part of the AD7837/AD7847 family of dual 12-bit DACs. While functionally similar to the AD7837, it differs in interface logic; the AD7847 utilizes dedicated Chip Select pins (CSA, CSB) for channel selection, whereas the AD7837 uses address lines (A0, A1) and a global LDAC pin. Both share identical static and dynamic performance characteristics.

Replacement Considerations

The AD7837BRZ is a functional alternative within the same family but requires different interface logic due to its address-based control scheme. Other variants such as AD7847ARZ (SOIC) or AD7847ANZ (DIP) offer the same electrical performance in different packages.