AD7853ANZ

Overview

The AD7853ANZ is a 12-bit, single-channel successive approximation register (SAR) analog-to-digital converter manufactured by Analog Devices. It operates from a single 3 V to 5.5 V supply and supports a throughput rate of 200 kSPS with a maximum master clock frequency of 4 MHz. The device features a pseudo-differential input range of 0 V to VREF or bipolar ±VREF/2, selectable via the AMODE pin. Power consumption is typically 20 mW at 5 V and 6.85 mW at 3 V in normal mode, with automatic power-down reducing dissipation to 25 mW post-conversion. It includes internal self-calibration and system calibration capabilities to maintain accuracy over temperature variations.

Feature Summary

• Integrated track-and-hold amplifier acquires signals within 500 ns using a pseudo-differential sampling scheme.
• Flexible serial interface compatible with standard SPI, QSPI, 8051, and microprocessor protocols.
• On-chip calibration logic performs automatic self-calibration on power-up and supports system offset/gain adjustments.
• Operates as a read-only ADC upon reset without requiring software configuration.

Applications

• Battery-powered portable systems such as personal digital assistants and mobile communications devices.
• Medical instrumentation requiring high precision and low power consumption.
• Pen computers and handheld data acquisition terminals.
• Industrial control systems and high-speed modems.

Procurement Notes

Verify the specific grade suffix (e.g., AN for commercial grade) against the required operating temperature range of -40°C to +85°C. Confirm package availability, as the 'N' suffix denotes a 24-lead plastic DIP. Ensure reference voltage requirements align with the external REFOUT capability or internal 2.5 V reference constraints.

Selection Notes

Select the AD7853ANZ when a 200 kSPS sampling rate is required compared to the lower-power AD7853L variant. Consider the 24-lead DIP package if through-hole mounting is necessary for the application board. Evaluate the need for bipolar input ranges, which requires biasing AIN(-) to VREF/2 when AMODE is set high.

Part Context

The AD7853ANZ belongs to the AD7853 family of 12-bit SAR ADCs designed for speed and low power efficiency. It shares architectural similarities with the AD7853L but offers higher throughput. The component is part of Analog Devices' broader portfolio of data converters, often paired with evaluation boards like EVAL-AD7853CB for design verification.

Replacement Considerations

The AD7853L series serves as the low-power alternative with reduced throughput. For direct pin-compatible replacements, verify if the AD7853BR or AD7853AR variants meet the specific linearity and temperature requirements, noting that package types differ between SOIC, SSOP, and DIP options.