AD7224CQ

Overview

The AD7224CQ is an 8-bit voltage-output digital-to-analog converter (DAC) with integrated output amplifiers, fabricated on a monolithic CMOS chip. It features double-buffered interface logic consisting of input and DAC registers, allowing simultaneous updates in multi-DAC systems. The device operates with single or dual supplies, supporting reference voltages from +2 V to +12.5 V. Key specifications include a total unadjusted error of ±1 LSB maximum over the operating temperature range, a settling time of 5 μs for positive full-scale changes, and TTL/CMOS compatible digital inputs. The CQ version provides an industrial temperature range of –40 °C to +85 °C and utilizes a 18-pin ceramic DIP package.

Feature Summary

• Integrated 8-bit DAC and unity gain output amplifier on a single LC2MOS CMOS chip
• Double-buffered interface logic enables simultaneous update of multiple devices
• Low total unadjusted error of ±1 LSB maximum over the full operating temperature range
• Operates with single (+15 V) or dual (+15 V / -5 V) power supplies

Applications

• Microprocessor-based data acquisition systems requiring simultaneous multi-channel updates
• Industrial control loops utilizing direct interfacing with standard 8-bit microprocessors
• System calibration cycles employing the zero override function via the RESET line

Procurement Notes

Verify the specific suffix 'CQ' corresponds to the 18-pin ceramic DIP package and the –40 °C to +85 °C industrial temperature range. Confirm that the required performance metrics, such as the ±1 LSB total unadjusted error, align with the dual supply specifications provided in the datasheet. Ensure ESD precautions are observed during handling due to the MOS gate construction.

Selection Notes

Select the AD7224CQ when a low-cost, high-reliability monolithic solution is required for 8-bit conversion with integrated buffering. The double-buffered architecture is essential for applications demanding synchronized updates across multiple DAC channels. Verify that the system can provide the necessary reference voltage stability, as the input impedance varies with the digital code. Consider the settling time requirements, noting that negative-going transitions may be slower in single-supply configurations.

Part Context

The AD7224 series comprises precision 8-bit DACs available in various packages including Plastic DIP, Ceramic DIP, SOIC, PLCC, and LCCC. The 'C' designation indicates the industrial temperature grade (–40 °C to +85 °C), while 'Q' specifies the 18-pin ceramic DIP form factor. This component belongs to Analog Devices' Linear Compatible CMOS family, designed for integration of high-speed digital logic and precision analog circuits on a single die.

Replacement Considerations

Public confirmed substitute part numbers: None.