AD7247AAR

Overview

The AD7247AAR is a dual 12-bit voltage-output digital-to-analog converter (DAC) fabricated in LC2MOS technology. It integrates two independent DAC channels, on-chip Zener voltage reference, and buffered output amplifiers on a single monolithic CMOS chip. The device features a parallel loading structure with separate Chip Select inputs for each DAC and a common Write input. It supports operation from +12 V to +15 V supplies, offering unipolar (0 V to +5 V, 0 V to +10 V) or bipolar (±5 V) output ranges via the ROFS pin configuration. Key electrical parameters include a typical settling time of 8 µs, ±1 LSB relative accuracy, and low power consumption of 165 mW typ in single supply mode.

Feature Summary

• Dual 12-bit DAC architecture with integrated 5 V Zener reference and output buffer amplifiers
• Parallel interface with individual Chip Select (CSA/CSB) and common Write (WR) inputs
• Configurable output ranges: 0–5 V, 0–10 V (unipolar), or ±5 V (bipolar)
• Improved interface speed with 30 ns typical data setup time

Applications

• Microprocessor-based data acquisition systems
• Industrial process control loops
• Programmable gain amplifier biasing
• Waveform generation circuits

Procurement Notes

Verify the specific suffix 'R' indicates the SOIC-24 package option when sourcing. Confirm temperature grade requirements, as the 'A' suffix denotes the industrial range (-40°C to +85°C). Check for military-grade variants if MIL-STD-883 compliance is required by adding '/883B' to the part number. Ensure ESD precautions are observed during handling due to CMOS sensitivity.

Selection Notes

Select the AD7247AAR over the AD7237A variant if a direct 12-bit parallel interface is preferred, eliminating the need for double-buffered 8-bit write cycles. Verify that the system requires separate Chip Select lines for independent DAC updates. Ensure the supply voltage range (+12 V to +15 V) aligns with the available power rails. Consider the SOIC-24 package dimensions against PCB space constraints.

Part Context

The AD7247AAR belongs to the AD7237A/AD7247A family, which serves as an enhanced version of the industry-standard AD7237/AD7247. This family improves upon previous generations by supporting wider supply voltages (12 V to 15 V), faster interface times, and better reference stability with respect to VDD variations. It utilizes Linear Compatible CMOS (LC2MOS) process technology.

Replacement Considerations

The AD7247ABR offers improved accuracy (±1/2 LSB max) compared to the AD7247AAR (±1 LSB max) within the same package and temperature range. For extended temperature applications (-55°C to +125°C), the AD7247ATQ is the compatible alternative. The AD7237AAR provides a similar function but uses an 8-bit wide double-buffered interface instead of parallel 12-bit loading.