AD7847BRZ-REEL

Overview

The AD7847BRZ-REEL is a dual 12-bit monolithic multiplying digital-to-analog converter (MDAC) manufactured by Analog Devices Inc. It integrates two complete DAC channels with internal output amplifiers in a 24-lead SOIC package. The device operates on dual power supplies ranging from ±14.25 V to ±15.75 V and features a parallel interface controlled by chip select inputs CSA and CSB, along with a write input WR. Key performance specifications include a typical settling time of 3 µs to within ±0.5 LSB, a unity gain small-signal bandwidth of 750 kHz, and a full-power bandwidth of 175 kHz. Relative accuracy is specified at ±1/2 LSB maximum for the B version.

Feature Summary

• Dual 12-bit MDAC architecture with integrated buffered output amplifiers
• Parallel interface with independent Chip Select inputs (CSA, CSB) and common Write input (WR)
• Internal feedback resistors eliminate external components required for basic operation
• High channel-to-channel isolation of -95 dB typ and low digital feedthrough of 1 nV·s typ

Applications

• Automatic Test Equipment
• Function Generation and Waveform Reconstruction
• Programmable Power Supplies
• Synchro Applications
• Analog Panning Circuits

Procurement Notes

Verify that the ordering suffix REEL indicates reel packaging as per distributor listings. Confirm the B version designation corresponds to the ±1/2 LSB relative accuracy specification rather than the A version's ±1 LSB. Ensure the procurement source provides valid RoHS compliance documentation and moisture sensitivity level details consistent with the SOIC-24 package requirements.

Selection Notes

Select the AD7847BRZ-REEL when a parallel interface with independent channel selection is required, distinguishing it from the AD7837 which uses an 8-bit bus structure. Choose the B version for tighter linearity specifications (±1/2 LSB). Ensure the system design accommodates the ±15 V supply requirement and that the 3 µs settling time meets the application's speed constraints.

Part Context

This component belongs to the AD7837/AD7847 family of dual 12-bit multiplying DACs. While functionally similar to the AD7837, the AD7847 utilizes a distinct 12-bit parallel loading structure with separate chip selects for each channel, whereas the AD7837 employs an 8-bit data bus with address lines for latch selection. Both share identical analog performance characteristics and pinouts.

Replacement Considerations

The AD7847ARZ serves as a tube-packaged alternative with identical electrical specifications. For applications requiring an 8-bit microprocessor interface, the AD7837BRZ is the functional equivalent but requires different control logic due to its MSB/LSB latch structure.