AD7228KNZ

Overview

The AD7228KNZ 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 separate on-chip latches for each DAC, accessed via a common 8-bit parallel data bus and three address lines (A0-A2). It operates with dual supplies (VDD: 10.8 V to 16.5 V; VSS: -5 V ± 10%) or a single 15 V supply. Key electrical specifications include a settling time of 5 µs to ±1/2 LSB, differential nonlinearity (DNL) of ±1 LSB, and integral nonlinearity (INL) of ±1 LSB. The package is a 24-lead skinny PDIP.

Feature Summary

• Octal architecture with eight independent 8-bit DACs and individual output buffers.
• Parallel microprocessor-compatible interface with TTL/CMOS levels and 95 ns write pulse compatibility.
• Guaranteed monotonic operation with ±1 LSB DNL and INL specifications.
• Supports single-supply (15 V) or dual-supply (+15 V/-5 V) operation.

Applications

• Automated test equipment requiring multi-channel signal generation.
• Industrial process control systems utilizing multiple analog outputs.
• Programmable power supplies and setpoint controllers.

Procurement Notes

Verify the suffix KNZ indicates the K grade version in the 24-lead PDIP package. Confirm that the specific revision of the datasheet matches the production lot requirements. Ensure that the ordering documentation explicitly lists the Analog Devices manufacturer part number to avoid confusion with other grades such as B or L.

Selection Notes

Select the AD7228KNZ when eight isolated 8-bit channels are required in a single component. The K grade offers ±2 LSB total unadjusted error compared to ±1 LSB for the B/L/C grades. Verify that the system can accommodate the 2 kΩ minimum load resistance and that the 5 µs settling time meets the application's speed requirements. Ensure the PCB layout accommodates the 24-lead PDIP footprint.

Part Context

The AD7228 series belongs to Analog Devices' LC2MOS family of high-speed linear-compatible CMOS DACs. The KNZ variant specifically denotes the commercial temperature range (-40°C to +85°C) and the K performance grade. This component serves as a cost-effective solution for applications needing multiple low-resolution analog outputs without external buffering components.

Replacement Considerations

The AD7228BKNZ provides improved accuracy with ±1 LSB TUE while maintaining the same pinout and package. The AD7228ABRZ offers surface-mount SOIC packaging with similar electrical characteristics. Cross-referencing should verify that the replacement part supports the required dual or single supply voltages and maintains the 8-bit resolution.