AD7822BR-REEL

Overview

The AD7822BR-REEL is an 8-bit, single-channel sampling analog-to-digital converter (ADC) from Analog Devices. It features a maximum throughput of 2 MSPS and a conversion time of 420 ns. The device includes an on-chip track-and-hold amplifier and a 2.5 V reference with ±2% tolerance. Operating from a single supply of 3 V ± 10% or 5 V ± 10%, it utilizes a flexible parallel interface with an End-of-Conversion (EOC) pulse for standalone operation. Key specifications include a Signal-to-(Noise + Distortion) Ratio of 48 dB min at 2 MHz sampling, Integral Nonlinearity of ±0.75 LSB max, and Differential Nonlinearity of ±0.75 LSB max.

Feature Summary

• Integrates an 8-bit half-flash ADC architecture with a dedicated track-and-hold amplifier for high-speed signal acquisition.
• Features automatic power-down functionality triggered by the CONVST pin state at the end of conversion to minimize power consumption.
• Includes an on-chip 2.5 V voltage reference and a VMID pin for adjustable analog input span centering within the supply range.

Applications

• Data acquisition systems
• DSP front ends
• Disk drives
• Mobile communication systems

Procurement Notes

Verify the specific package variant against the ordering guide, as the AD7822 series supports multiple packages including PDIP, SOIC, and TSSOP. Confirm that the BR suffix corresponds to the industrial temperature range (-40°C to +85°C). Ensure compatibility with the required supply voltage (3 V or 5 V) and check for any discontinuance notices associated with this specific reel packaging configuration.

Selection Notes

Select the AD7822BR-REEL when a single-channel, high-speed 8-bit conversion is required with minimal external component count. The integrated reference and track-and-hold simplify design compared to discrete solutions. Consider the parallel interface requirements and ensure the microprocessor can handle the 420 ns conversion time and data access timing constraints specified in the datasheet.

Part Context

The AD7822 is part of the AD7822/AD7825/AD7829 family of high-speed sampling ADCs. While the AD7825 offers four channels and the AD7829 offers eight, the AD7822 provides a single-channel solution. All variants share identical core performance characteristics, including the 2 MSPS throughput and 8-bit resolution, differing primarily in channel count and package pinout.

Replacement Considerations

Direct replacements within the same family include the AD7825BR (4-channel) and AD7829BR (8-channel), provided additional channels are acceptable. For single-channel applications, verify if other Analog Devices 8-bit SAR ADCs meet the 2 MSPS speed and parallel interface requirements.