AD7808BNZ

Overview

The AD7808BNZ is an octal 10-bit digital-to-analog converter (DAC) manufactured by Analog Devices Inc. It operates from a single +3.3 V to +5.5 V power supply and incorporates an on-chip reference. The device features eight buffered voltage outputs, double-buffered data inputs for simultaneous updates via the LDAC pin, and serial SPI-compatible interface control. Key electrical specifications include a maximum settling time of 4 µs, ±4 LSB relative accuracy, and ±0.125 LSB typical differential nonlinearity. It supports internal or external reference selection and includes programmable power-down modes.

Feature Summary

• Octal configuration with eight independent 10-bit DAC channels in a 24-pin PDIP package
• Serial interface utilizing FSIN, CLKIN, and SDIN lines for data and control register access
• Integrated 1.23 V bandgap reference output with dual external reference capability via REFIN
• Double-buffered architecture allowing simultaneous analog output updates through asynchronous LDAC

Applications

• Optical disk drives requiring multi-channel signal generation
• Process control systems for voltage setpoint management
• Instrumentation and communication equipment
• Automatic calibration circuits
• Trim potentiometer replacement applications

Procurement Notes

Verify component authenticity upon receipt as the AD7808BNZ is listed as obsolete. Confirm package integrity and pin alignment against the 24-PDIP specification. Check datasheet revisions for any parameter changes. Ensure ESD precautions are observed during handling due to CMOS construction sensitivity.

Selection Notes

Select the AD7808BNZ when eight isolated 10-bit analog outputs are required within a single package. Choose this part over parallel-load variants if system design constraints favor serial data transmission. Verify that the +3.3 V to +5.5 V supply range aligns with the target application's power infrastructure and that the 4 µs settling time meets system speed requirements.

Part Context

The AD7808BNZ belongs to the AD7804/AD7805/AD7808/AD7809 family of 10-bit DACs. It is distinguished by its octal channel count and serial loading mechanism, contrasting with the quad-channel AD7804 and the parallel-load AD7809. The 'B' grade indicates specific accuracy limits, while 'NZ' denotes RoHS compliance and lead-free termination.

Replacement Considerations

The AD7808BRZ is a direct surface-mount equivalent offering identical functionality in a 24-lead SOIC package. Designers transitioning from the obsolete AD7808BNZ should account for the footprint change from through-hole PDIP to surface-mount SOIC.