AD7858ARZ-REEL

Overview

The AD7858ARZ-REEL is a 12-bit successive approximation register (SAR) analog-to-digital converter manufactured by Analog Devices Inc. It operates from a single 3 V to 5.5 V supply and supports a throughput rate of 200 kSPS. The device features eight single-ended or four pseudo-differential analog inputs, selectable via the control register. It utilizes a flexible serial interface compatible with SPI, QSPI, and 8051 protocols. Power consumption is typically 25 mW in normal mode at 3 V. The component is housed in a 24-lead SOIC package.

Feature Summary

• Integrated system and self-calibration capabilities with automatic calibration on power-up to maintain accuracy over time and temperature variations.
• Flexible power management options including automatic power-down after conversion and multiple sleep modes for low-power applications.
• Versatile serial I/O port supporting standard communication protocols such as SPI, QSPI, and 8051 microprocessor interfaces.

Applications

• Battery-powered systems including personal digital assistants and mobile communications devices
• Medical instruments requiring precise signal acquisition
• Instrumentation and control systems

Procurement Notes

Verify the specific suffix 'REEL' indicates tape-and-reel packaging rather than tube packaging when sourcing components. Confirm that the 'A' grade designation matches the required performance specifications for integral nonlinearity and gain error. Ensure the operating voltage range aligns with the 3 V to 5.5 V specification provided in the datasheet.

Selection Notes

Select the AD7858ARZ-REEL for applications requiring high-speed sampling up to 200 kSPS with 12-bit resolution. Consider the AD7858L variant if lower power consumption is prioritized over maximum speed. Ensure the design accommodates the 24-lead SOIC package dimensions and thermal requirements specified for commercial temperature ranges.

Part Context

This component belongs to the AD7858 family of high-speed, low-power ADCs. The AD7858 model is optimized for speed, while the AD7858L variant focuses on reduced power dissipation. Both share similar architectural features but differ in maximum clock frequencies and power profiles.

Replacement Considerations

The AD7858BRZ is listed as a parameter-equivalent substitute within the same product line. Verify pin compatibility and electrical specifications before substitution.

FAQ

What is the input voltage range for the AD7858ARZ?

The analog input voltage range is from 0 V to VREF, where VREF can be an external reference or the internal 2.5 V reference.

How does the device handle calibration?

The AD7858 supports both system and self-calibration. It can perform automatic self-calibration on power-up if a capacitor is connected to the CAL pin, or it can be triggered via software commands.

What is the typical power consumption in normal mode?

Typical power dissipation is 25 mW when operating at 3 V in normal mode.