AD7853BRZ

Overview

The AD7853BRZ is a high-speed, low-power, 12-bit successive approximation register (SAR) analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from a single 3 V to 5.5 V power supply and supports a throughput rate of 200 kSPS. The device features a pseudo-differential input sampling scheme with an acquisition time of 400 ns. It includes system and self-calibration capabilities with autocalibration on power-up to maintain accuracy over temperature variations. Power consumption is typically 20 mW at 5 V and 12 mW at 3 V in normal mode, dropping to 25 µW after conversion. The ADC provides flexible serial interface compatibility with SPI, QSPI, 8051, and microprocessor systems.

Feature Summary

• Supports read-only operation upon power-up without requiring software configuration.
• Integrates automatic self-calibration and system calibration functions for precision maintenance.
• Features flexible serial communication interfaces compatible with standard protocols.
• Includes automatic power-down functionality following each conversion cycle.

Applications

• Battery-powered medical instruments
• Pen computers and personal digital assistants
• Instrumentation and control systems
• High-speed modems

Procurement Notes

Verify the specific grade suffix 'B' corresponds to the required linearity specifications and operating temperature range before procurement. Confirm package availability matches the design requirements, as the BRZ designation indicates a 24-lead SOIC package. Ensure that the ordering documentation explicitly lists the component as the AD7853 variant rather than the lower-speed AD7853L version to guarantee the 200 kSPS performance target.

Selection Notes

Select the AD7853BRZ when a 200 kSPS sampling rate is required alongside low power consumption. Choose this part over the AD7853L if higher throughput is necessary, noting the increased power dissipation. Consider the pseudo-differential input architecture for noise rejection benefits. Verify that the external reference voltage range aligns with the 1.2 V to AVDD specification. Ensure the system timing allows for the specified track-and-hold acquisition period.

Part Context

The AD7853BRZ belongs to the AD7853/AD7853L family of 12-bit sampling ADCs designed for single-supply applications. This family distinguishes between speed-optimized (AD7853) and low-power-optimized (AD7853L) variants. The BRZ suffix specifically denotes the commercial-grade B version housed in a 24-lead Small Outline Integrated Circuit (SOIC) package. This component serves as a bridge between high-speed data acquisition and battery-operated constraints.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Designers should verify pinout and electrical parameter compatibility if considering alternative SAR ADCs from other manufacturers.