AD7922ARM

Overview

The AD7922ARM is a dual-channel, 12-bit successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from a single power supply 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 capable of handling input frequencies exceeding 6 MHz. Key electrical specifications include a typical signal-to-noise ratio (SNR) of 72.5 dB at 100 kHz input frequency, a maximum integral nonlinearity (INL) of ±1.5 LSB, and a differential nonlinearity (DNL) of -0.9/+1.5 LSB. Power consumption is typically 4.8 mW at 1 MSPS with 3 V supplies. The component utilizes a flexible serial interface compatible with SPI, QSPI, MICROWIRE, and DSP standards.

Feature Summary

• Dual-channel architecture with on-chip multiplexing for efficient data acquisition
• Flexible serial interface supporting multiple standard communication protocols
• Integrated track-and-hold amplifier for wide bandwidth signal capture
• Internal reference derived from the power supply to maximize dynamic range

Applications

• Battery-powered systems such as personal digital assistants
• Medical instruments requiring low power consumption
• Mobile communications equipment
• Instrumentation and control systems
• Data acquisition systems

Procurement Notes

Verify the specific package variant when ordering, as the AD7922 series includes both MSOP and TSOT options. Confirm that the A Grade temperature rating meets the operational requirements of the target environment. Ensure the design accounts for the internal reference source derived from VDD rather than an external precision reference.

Selection Notes

Select the AD7922ARM when a 12-bit resolution is required alongside high-speed sampling capabilities. This model is suitable for applications needing two single-ended inputs processed at rates up to 1 MSPS. Consider the power dissipation characteristics relative to the available thermal headroom in the enclosure. Verify compatibility with the host microcontroller's serial clock speed limits.

Part Context

The AD7922ARM belongs to the AD7912/AD7922 family of high-speed, low-power ADCs. While the AD7912 offers 10-bit resolution, the AD7922 provides 12-bit accuracy within the same form factor and pinout configuration. Both devices share identical timing characteristics and interface protocols, allowing for potential design flexibility between resolution requirements without changing the physical footprint.

Replacement Considerations

The AD7912 serves as a lower-resolution alternative within the same package. No other direct cross-model replacements are documented in the provided datasheet.