AD7922AUJ-REEL

Overview

The AD7922AUJ-REEL is a dual-channel, 12-bit successive approximation analog-to-digital converter manufactured by Analog Devices Inc. It operates on a single supply voltage ranging from 2.35 V to 5.25 V and supports throughput rates up to 1 MSPS. The device features an internal track-and-hold amplifier with a wide input bandwidth and utilizes an external reference derived from the power supply. It communicates via a flexible high-speed serial interface compatible with SPI, QSPI, MICROWIRE, and DSP standards. Key electrical specifications include a typical signal-to-noise ratio of 72.5 dB at 100 kHz input frequency, a maximum conversion time of 888 ns, and low power consumption of approximately 15.5 mW at 5 V supplies during operation.

Feature Summary

• Dual-channel architecture with integrated track-and-hold amplifier for simultaneous data acquisition
• Flexible serial interface supporting multiple communication protocols including SPI and MICROWIRE
• Daisy-chain capability allowing multiple devices to be connected for expanded system control
• Low power management with standby mode reducing current consumption to 1 µA maximum

Applications

• Battery-powered systems such as personal digital assistants and mobile communications
• Medical instruments requiring precise analog signal digitization
• Data acquisition systems and instrumentation control applications
• High-speed modems and optical sensor interfaces

Procurement Notes

Verify that the ordering suffix matches the required reel packaging configuration. Confirm the specific grade (A Grade) and temperature range requirements against the application environment. Ensure the component is sourced from authorized distributors to guarantee authenticity and adherence to manufacturing standards.

Selection Notes

Select this component when a 12-bit resolution is required for dual-channel signal processing. Consider the operating voltage range and power constraints relative to the system design. Evaluate the need for daisy-chain functionality if multiple converters are necessary for the application architecture.

Part Context

This part belongs to the AD7912/AD7922 family of high-speed, low-power ADCs. The AD7922 variant specifically provides 12-bit resolution compared to the 10-bit AD7912. Both share identical pinouts and operational characteristics, differing primarily in resolution and associated dynamic performance metrics.

Replacement Considerations

The AD7912AUJ-REEL serves as a functional substitute within the same package if 10-bit resolution is sufficient. Verify compatibility regarding resolution requirements and dynamic performance specifications before implementation.

FAQ

How is the reference voltage determined for the AD7922?

The AD7922 does not contain an internal reference; it derives its reference directly from the VDD power supply, allowing for the widest dynamic input range.

What is the maximum serial clock frequency supported?

The device supports a maximum serial clock frequency of 18 MHz, which enables the full 1 MSPS throughput rate.

Does the device introduce pipeline delays during conversion?

No, the AD7922 features no pipeline delays, providing accurate control of the sampling instant via the CS input.