AD7921AUJ-R2

Overview

The AD7921AUJ-R2 is a dual-channel, 12-bit successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from a single supply voltage ranging from 2.35 V to 5.25 V and supports throughput rates up to 250 kSPS. 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 a 100 kHz input frequency, a maximum Integral Nonlinearity (INL) of ±1.5 LSB, and a maximum Differential Nonlinearity (DNL) of -0.9/+1.5 LSB. Power consumption is typically 4 mW at 250 kSPS with 3 V supplies. The component is housed in an 8-lead TSOT package.

Feature Summary

• Dual-channel architecture with on-chip multiplexing for efficient signal acquisition.
• Internal reference derived from the power supply to maximize dynamic input range.
• Flexible serial interface compatible with standard microprocessor protocols.
• Low power operation with dedicated standby mode for energy efficiency.

Applications

• Battery-powered personal digital assistants
• Medical instrumentation systems
• Mobile communications devices
• Data acquisition systems

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and reel specifications. Ensure compatibility with system voltage requirements before integration. Confirm availability through authorized distributors as stock levels may vary. Check for RoHS compliance status if required by local regulations.

Selection Notes

Select this component when a 12-bit resolution is required for dual-channel applications. Consider the 250 kSPS throughput rate relative to the input signal bandwidth. Evaluate the TSOT package constraints for PCB layout. Compare performance metrics against the AD7911 if lower resolution is acceptable for cost reduction.

Part Context

This part belongs to the AD7911/AD7921 family of low-power, high-speed ADCs. The AD7921 variant specifically provides 12-bit resolution compared to the 10-bit AD7911. Both share identical pinouts, interfaces, and power characteristics, differing primarily in conversion accuracy and data word length.

Replacement Considerations

The AD7911AUJ-R2 is a functional substitute within the same family but offers 10-bit resolution instead of 12-bit. Verify that the reduced resolution meets application accuracy requirements before substitution.