AD7225BRS

Overview

The AD7225BRS is an Analog Devices LC2MOS quad 8-bit digital-to-analog converter (DAC) featuring integrated output buffer amplifiers. It provides four independent voltage outputs with separate reference inputs for each channel, supporting simultaneous updates via a double-buffered interface. The device operates on single or dual supplies, typically VDD of 11.4 V to 16.5 V and VSS of −5 V. Key static performance metrics include ±1 LSB relative accuracy and ±1 LSB differential nonlinearity for the B version. Dynamic characteristics feature a settling time of 4 μs to ±½ LSB and a slew rate of 2.5 V/μs. The component utilizes a parallel interface compatible with TTL and CMOS logic levels.

Feature Summary

• Quad 8-bit DAC architecture with individual buffered voltage outputs
• Separate reference input per channel allowing flexible signal handling
• Double-buffered parallel interface enabling simultaneous multi-channel updates
• LC2MOS process technology integrating high-speed digital and precision analog circuits

Applications

• Programmable transversal filters requiring precise tap weighting
• Digital word multiplication systems utilizing multiple DAC channels
• Microprocessor-controlled data acquisition and signal generation systems

Procurement Notes

Verify the specific suffix 'BRS' against the manufacturer's current ordering guide to confirm package type and temperature range specifications. Ensure compatibility with system power supply rails, as the device requires specific overhead voltages between VDD and reference inputs for optimal performance. Confirm pinout alignment with PCB layout designs, particularly regarding the separation of analog and digital grounds.

Selection Notes

Select the AD7225BRS when four independent 8-bit voltage outputs are required with minimal external component count. The B version offers improved total unadjusted error compared to the K version. Consider the package constraints of the SOIC-24 form factor if surface mount assembly is preferred over through-hole options. Evaluate the need for separate reference inputs versus shared references to determine if this flexibility justifies the design complexity.

Part Context

The AD7225 belongs to a family of monolithic CMOS DACs designed for applications requiring multiple channels on a single chip. It replaces discrete resistor ladder and amplifier combinations, reducing board space and improving reliability. The device is fabricated using ion-implanted linear-compatible CMOS processes to ensure high speed and linearity. It serves as a bridge between digital control systems and analog signal processing stages.

Replacement Considerations

The MX7225KCWG+ is a functionally similar quad 8-bit DAC from Analog Devices/Maxim Integrated. However, it features buffered voltage outputs and different nonlinearities (±0.5 LSB INL). Verify pinout compatibility and reference input configurations before substitution, as interface logic and power requirements may differ.