AD7228ABN

Overview

The AD7228ABN is an octal 8-bit digital-to-analog converter (DAC) manufactured by Analog Devices Inc. It integrates eight voltage-mode DACs with output buffer amplifiers and interface logic on a single monolithic chip fabricated using LC2MOS technology. The device operates with dual supplies (VDD = 10.8 V to 16.5 V, VSS = −5 V ± 10%) or a single supply (VDD = 13.5 V to 16.5 V). Key electrical parameters include a maximum settling time of 5 µs for positive full-scale changes and 7 µs for negative changes in single-supply mode. Static performance guarantees differential nonlinearity (DNL) of ±1 LSB and integral nonlinearity (INL) of ±1/2 LSB for the B version. The component utilizes a parallel 8-bit data bus with individual latches controlled by A0-A2 address inputs and an active-low WR signal.

Feature Summary

• Octal architecture containing eight independent 8-bit voltage-mode DACs with integrated unity-gain buffer amplifiers.
• Microprocessor-compatible interface supporting TTL/CMOS levels with a common 8-bit data bus and individual latch control via A0-A2 addresses.
• Flexible power supply operation allowing dual supplies (±5 V nominal) or single supply (up to 16.5 V), including specific 5 V single-supply capability.
• High-speed dynamic performance with a typical voltage output slew rate of 2 V/µs and settling times within 5–7 µs.

Applications

• Automated test equipment requiring programmable timing deskew and coarse/fine voltage adjustments.
• Multi-channel data acquisition systems utilizing microprocessor-controlled analog signal generation.
• Industrial instrumentation requiring multiple isolated or buffered analog outputs from a single digital source.

Procurement Notes

Verify the specific suffix 'ABN' against the manufacturer's current ordering guide to confirm package type and temperature grade. The datasheet indicates availability in 24-lead PDIP, CERDIP, SOIC, and 28-lead PLCC packages; ensure the physical footprint matches the design requirements. Confirm RoHS compliance status as specifications may vary by manufacturing revision. Cross-reference pin configurations carefully, as unused pins (DNC) must remain unconnected to prevent device malfunction.

Selection Notes

Select the AD7228ABN when an application requires eight simultaneous analog outputs from a single IC to reduce board space. Ensure the reference voltage source can handle the varying input impedance (2 kΩ to infinity) caused by code-dependent loading on the VREF pin. For single-supply designs, verify that the negative settling time meets system requirements, as it is slower near 0 V compared to dual-supply operation. Check that the load resistance is at least 2 kΩ to maintain specified accuracy and output swing capabilities.

Part Context

The AD7228 belongs to the AD7228 family of octal DACs produced by Analog Devices. It is fabricated on an ion-implanted, high-speed, linear-compatible CMOS (LC2MOS) process designed to integrate precision analog circuits with high-speed digital logic. The device is part of a broader portfolio of data converters aimed at simplifying multi-channel analog interface designs in industrial and test applications.

Replacement Considerations

Direct replacements within the same family include the AD7228ACPZ (PLCC package) and AD7228ABRZ (SOIC package). Verify pin compatibility, particularly regarding the Do Not Connect (DNC) pins which are present in the PLCC variant but absent in the 24-lead packages. Ensure the replacement part supports the required supply voltage range and thermal operating conditions (-40°C to +85°C).