AD7858ARZ

Overview

The AD7858ARZ is a high-speed, low-power 12-bit Analog-to-Digital Converter (ADC) manufactured by Analog Devices Inc. It operates from a single 3 V to 5.5 V supply and features an 8-channel multiplexer supporting eight single-ended or four pseudo-differential inputs. The device utilizes a Successive Approximation Register (SAR) architecture with a throughput rate of 200 kSPS. It includes system and self-calibration capabilities that activate on power-up to ensure accuracy over temperature variations. The ADC communicates via a flexible serial interface compatible with SPI, QSPI, and µP standards, housed in a 24-lead SOIC package.

Feature Summary

• Integrated system and self-calibration mechanisms with automatic initialization upon power-up to maintain measurement precision across varying temperatures.
• Configurable analog input multiplexer allowing selection between eight single-ended channels or four pseudo-differential pairs.
• Flexible digital serial interface supporting multiple communication protocols including SPI, QSPI, and standard microprocessor modes.
• Comprehensive power management options featuring automatic power-down states after conversion cycles to minimize energy consumption.

Applications

• Battery-powered portable systems such as personal digital assistants and mobile communications devices
• Medical instrumentation requiring precise signal acquisition
• Pen computers and handheld data collection terminals
• Industrial instrumentation and control systems

Procurement Notes

Verify the specific ordering suffix against manufacturer documentation to confirm package type and temperature range specifications. Ensure compatibility with existing board layouts regarding the 24-lead SOIC footprint. Confirm that the selected variant meets the required operating voltage and sampling rate constraints for the target application environment.

Selection Notes

Select this component when a balance of speed and power efficiency is required for multi-channel data acquisition. The AD7858ARZ is suitable for applications needing 200 kSPS performance with 12-bit resolution. Consider the integrated calibration features if long-term stability without external trimming is necessary. Evaluate the serial interface requirements to ensure compatibility with the host controller's available ports.

Part Context

The AD7858ARZ belongs to the AD7858 family of 12-bit sampling ADCs from Analog Devices. This series distinguishes between speed-optimized and low-power variants. The 'A' grade specifies the commercial temperature range of -40°C to +85°C. The 'R' suffix indicates the Small Outline Integrated Circuit (SOIC) package configuration used for surface-mount assembly.

Replacement Considerations

The AD7858BRZ is a parameter-equivalent alternative within the same product family offering improved linearity specifications. Verify pinout compatibility and electrical characteristics before substitution.