AD7837BQ

Overview

The AD7837BQ is a dual 12-bit monolithic multiplying digital-to-analog converter (MDAC) featuring integrated output amplifiers, manufactured by Analog Devices Inc. It utilizes LC2MOS technology to achieve high-speed performance with a typical voltage output settling time of 3 µs to within ±1/2 LSB. The device offers a relative accuracy of ±1/2 LSB and operates over an industrial temperature range of –40 °C to +85 °C. Designed for parallel loading, it accepts an 8-bit least significant word and a 4-bit most significant word via separate input latches, updating both channels simultaneously through the LDAC pin. The component is housed in a 24-lead Cerdip package.

Feature Summary

• Dual 12-bit MDACs with integrated output amplifiers providing ±10 V swing across a 2 kΩ load
• High speed performance with 3 µs typical settling time and 11 V/µs slew rate
• ±1/2 LSB relative accuracy ensuring monotonic operation without missing codes
• Parallel loading structure allowing independent access to MSB and LSB input latches

Applications

• Automatic Test Equipment requiring precise waveform generation
• Programmable power supplies utilizing 4-quadrant multiplication capabilities
• Synchro-to-digital or digital-to-synchro conversion systems
• Function generators and waveform reconstruction circuits

Procurement Notes

Verify the specific ordering suffix 'Q' corresponds to the 24-lead Cerdip package variant when sourcing components. Confirm that the required temperature range aligns with the B version specification of –40 °C to +85 °C. Ensure electrostatic discharge precautions are implemented during handling, as the device is sensitive to high-energy charges. Cross-reference the datasheet revision to confirm interface logic compatibility with the target microprocessor architecture.

Selection Notes

Select the AD7837BQ when simultaneous dual-channel updates are required using a parallel data bus interface. This model is suitable for applications demanding ±1/2 LSB linearity and fast settling times under standard industrial temperature conditions. Consider the AD7847 if a serial input loading structure or single-chip select per channel is preferred instead of the AD7837's address-based parallel loading scheme. Verify power supply requirements match the specified ±15 V nominal range for optimal performance.

Part Context

The AD7837BQ belongs to the AD7837/AD7847 family of complete dual 12-bit multiplying DACs from Analog Devices. While the AD7837 utilizes a parallel loading structure with separate MSB and LSB latches, the sibling AD7847 employs a serial input loading format. Both share identical electrical specifications and internal circuitry, differing primarily in digital interface configuration. The 'B' designation indicates ±1/2 LSB accuracy, whereas 'A' denotes ±1 LSB accuracy.

Replacement Considerations

The AD7837BRZ serves as a direct functional replacement offering identical specifications in a 24-lead SOIC surface-mount package. For ceramic DIP packaging alternatives, verify availability of other accuracy grades such as the AD7837AQ, noting its ±1 LSB specification differs from the B version.