AD7853AR

Overview

The AD7853AR is a 12-bit successive approximation analog-to-digital converter (ADC) from Analog Devices, optimized for high-speed operation with a throughput rate of 200 kSPS. It operates on a single supply voltage ranging from 3.0 V to 5.5 V and features a pseudo-differential input architecture supporting unipolar or bipolar signal ranges. The device includes an internal track-and-hold amplifier that acquires signals within 400 ns. It supports flexible serial interfaces compatible with SPI, QSPI, and 8051 microprocessors. Key performance metrics include a typical Signal-to-Noise Ratio (SNR) of 72 dB and Total Harmonic Distortion (THD) of -78 dB at a 10 kHz input frequency.

Feature Summary

• Integrated self-calibration and system calibration capabilities ensure long-term accuracy across varying temperatures and time.
• Flexible power management options allow for automatic power-down after conversion and multiple sleep modes to minimize energy consumption.
• Versatile serial interface supports various communication protocols including SPI, QSPI, and µP-compatible modes via hardware pin selection.
• On-chip control registers enable software-configurable conversion start, reference selection, and output coding formats.

Applications

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

Procurement Notes

Verify the specific grade suffix (e.g., AR vs BR) against the required operating temperature range and linearity specifications. Confirm package type availability in SOIC-24 format. Ensure reference voltage requirements align with the external 2.5 V reference or internal buffer configuration. Check for RoHS compliance status if environmental regulations apply to the manufacturing process.

Selection Notes

Select the AD7853AR when maximum sampling speed up to 200 kSPS is required compared to the lower power AD7853L variant. Consider the 12-bit resolution and pseudo-differential inputs for applications needing moderate precision with reduced noise sensitivity. Evaluate the need for system calibration features to correct for external sensor gain and offset errors. Ensure the host microcontroller supports the selected serial interface mode and clock frequencies.

Part Context

The AD7853 belongs to a family of single-supply, 12-bit sampling ADCs manufactured by Analog Devices. It is designed to bridge the gap between high-speed data acquisition and low-power consumption. The 'AR' designation indicates a specific thermal and electrical grade packaged in a 24-lead Small Outline Integrated Circuit (SOIC). This component is part of a broader portfolio that includes variants optimized for different power-speed trade-offs.

Replacement Considerations

The AD7853L serves as the low-power alternative within the same family, offering 100 kSPS throughput. For direct pin-compatible upgrades requiring higher speed, verify if the AD7853 meets the new timing constraints. Cross-reference with other 12-bit SAR ADCs if interface compatibility or package footprint changes are acceptable.