AD7237AAR

Overview

The AD7237AAR is a dual 12-bit voltage-output digital-to-analog converter (DAC) from Analog Devices, packaged in a 24-lead Small Outline Integrated Circuit (SOIC). It integrates two complete DAC channels with on-chip output amplifiers and a Zener voltage reference. The device operates from single or dual power supplies ranging from +10.8 V to +16.5 V for VDD and -16.5 V to 0 V for VSS. Key electrical specifications include a maximum settling time of 8 µs, a typical power dissipation of 165 mW in single-supply mode, and an input data setup time of 30 ns. The part supports unipolar (+5 V, +10 V) and bipolar (±5 V) output ranges.

Feature Summary

• Dual 12-bit resolution with integrated buffered output amplifiers and internal 5 V reference.
• Improved interface speed with a typical 30 ns data setup time for direct microprocessor connection.
• Flexible power supply operation supporting single (+12 V to +15 V) or dual (±12 V to ±15 V) rails.
• Configurable output voltage ranges including 0 V to +5 V, 0 V to +10 V, and ±5 V via ROFS pins.

Applications

• Industrial process control systems requiring precise analog signal generation.
• Portable instrumentation utilizing single-supply operation for low power consumption.
• Microprocessor-based data acquisition systems interfacing via parallel 8-bit buses.
• Test and measurement equipment needing simultaneous dual-channel updates.

Procurement Notes

Verify the specific suffix 'R' confirms the SOIC-24 package variant when sourcing. Confirm the temperature grade corresponds to the industrial range (-40°C to +85°C) required for the application environment. Ensure that the ordering documentation specifies the A version accuracy class if tighter linearity tolerances are not critical, as B versions offer improved accuracy.

Selection Notes

Select the AD7237AAR over the AD7247A when interfacing with 8-bit microprocessors, as the AD7237A utilizes an 8+4 bit double-buffered loading structure compatible with standard 8-bit data buses. Choose this component if the design requires an asynchronous LDAC signal for synchronized multi-channel updates. Verify that the required output swing fits within the supported unipolar or bipolar configurations defined by the ROFS resistor connections.

Part Context

The AD7237AAR belongs to the DACPORT family, which combines precision analog circuits with CMOS logic on a monolithic LC2MOS chip. This integration eliminates the need for external trimming components typically required in discrete DAC designs. The 'A' designation indicates the industrial temperature grade and standard accuracy class, while 'AR' denotes the plastic SOIC package option.

Replacement Considerations

The AD7237ABR is a direct pin-compatible replacement offering improved relative accuracy (±1/2 LSB max vs ±1 LSB max) within the same industrial temperature range and SOIC package. For extended temperature applications (-55°C to +125°C), the AD7237ATQ is available in a ceramic QFP package, though physical footprint changes must be accounted for.