AD7228ABR

Overview

The AD7228ABR is an octal 8-bit digital-to-analog converter (DAC) fabricated on LC2MOS CMOS technology. It integrates eight voltage-mode DACs with output buffer amplifiers and interface logic on a single chip. The device features individual latches for each channel, controlled via a common 8-bit parallel data bus and address inputs (A0-A2). It operates with single or dual supplies, supporting VDD ranges from 10.8 V to 16.5 V and VSS from -5.5 V to -4.5 V. Key electrical parameters include a settling time of 5 µs to ±1/2 LSB, total unadjusted error of ±1 LSB (C version), and a maximum supply current of 20 mA. The component is housed in a 24-lead SOIC package.

Feature Summary

• Octal architecture with eight independent 8-bit DACs and integrated output buffers
• Microprocessor-compatible parallel interface with TTL/CMOS levels and 95 ns write pulse capability
• Flexible power supply operation supporting single (+15 V) or dual (+15 V/-5 V) configurations
• Monolithic LC2MOS process ensuring high speed and linearity without external trimming

Applications

• Automated test equipment requiring multi-channel signal generation
• Industrial control systems utilizing microprocessor-based architectures
• Programmable power supplies and setpoint controllers
• Data acquisition systems needing coarse/fine adjustment circuits

Procurement Notes

Verify the specific grade suffix (e.g., ABR vs. ABRZ) against the manufacturer's ordering guide to confirm RoHS compliance and temperature range specifications. Confirm pinout compatibility with the target PCB footprint, as the SOIC variant shares dimensions with PDIP/CERDIP packages but differs in lead style. Ensure supply voltage rails match the specified operational limits for the selected grade.

Selection Notes

Select the AD7228ABR when an octal configuration is required to minimize board space compared to discrete solutions. Choose this part if the application demands a parallel interface compatible with standard 8-bit microprocessors like the 8085 or Z80. Verify that the load requirements do not exceed the 2 kΩ minimum resistance specification. Consider the C-grade version if tighter accuracy specifications (±1 LSB TUE) are necessary over the commercial temperature range.

Part Context

The AD7228 belongs to the Analog Devices LC2MOS family of high-speed linear-compatible CMOS data converters. This series is designed to integrate precision analog circuits with high-speed digital logic on a single monolithic chip. The AD7228 specifically addresses applications requiring multiple low-resolution channels with fast update rates, distinguishing itself from higher-resolution single-channel DACs by its density and parallel addressing capabilities.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.