AD7228ACQ

Overview

The AD7228ACQ is an octal 8-bit voltage-mode digital-to-analog converter (DAC) fabricated on LC2MOS technology. It integrates eight DACs with output buffer amplifiers and interface logic on a single chip, eliminating the need for external trims. The device features individual latches for each channel, controlled via a common 8-bit parallel data bus and three address lines (A0-A2). It supports dual supplies (VDD: 10.8 V to 16.5 V; VSS: -5 V ± 10%) or single supply operation (VDD: 13.5 V to 16.5 V; VSS: GND). Key electrical specifications include a settling time of 5 µs for positive full-scale changes and 7 µs for negative changes in single-supply mode, with a maximum power dissipation of 1 W.

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 options supporting both dual (-5 V/+15 V) and single (+15 V/GND) configurations.
• High-speed performance with 5 µs settling time and guaranteed monotonicity.

Applications

• Automated test equipment requiring multi-channel signal generation.
• Industrial control systems utilizing coarse/fine adjustment circuits.
• Data acquisition systems needing programmable reference voltages.

Procurement Notes

Verify the specific suffix 'CQ' against the manufacturer's current ordering guide, as package and temperature grade variations exist within the AD7228 family. Confirm that the required package type matches the available options such as 24-lead PDIP, CERDIP, SOIC, or 28-lead PLCC. Ensure compatibility with the intended supply voltage range and load requirements before procurement.

Selection Notes

Select this component when multiple isolated DAC channels are required on a single board to reduce space. Choose the AD7228ACQ if the application demands high speed with a 95 ns write cycle. Consider the single-supply variant if system design constraints prohibit negative voltage rails, noting the slight increase in negative settling time compared to dual-supply operation.

Part Context

The AD7228 series belongs to Analog Devices' LC2MOS product line, designed to integrate high-speed digital logic with precision analog circuits. This monolithic approach reduces board space and increases reliability compared to discrete solutions. The device is part of a broader family including quad and dual DAC variants, sharing similar interface logic but differing in channel count and pinout configurations.

Replacement Considerations

Direct replacements depend on the specific package and grade. For 24-lead SOIC packages, consider the AD7228ABRZ or AD7228ACPZ. For through-hole applications, the AD7228KNZ or AD7228BQ may serve as alternatives. Verify that substitute parts meet the same settling time and accuracy specifications for the target application.