AD7875KR

Overview

The AD7875KR is a complete monolithic 12-bit analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It features an LC2MOS architecture with a 2 μs track-and-hold amplifier and an 8 μs successive approximation conversion time. The device operates from ±5 V power supplies and accepts a unipolar analog input range of 0 V to +5 V. It includes an on-chip 3 V buried Zener reference and offers parallel, byte, and serial digital interface options. Key performance metrics include a signal-to-noise ratio of 72 dB at a 10 kHz input frequency and a data access time of 57 ns. Typical power dissipation is 60 mW.

Feature Summary

• Integrates a 12-bit ADC, track-and-hold amplifier, internal clock, and voltage reference on a single chip.
• Provides versatile digital output formats including 12-bit parallel, two 8-bit bytes, and serial data.
• Features laser-trimmed internal clock for accurate conversion timing without external components.
• Designed for fast microprocessor interfacing with standard control inputs and low data access times.

Applications

• Data acquisition systems requiring 12-bit resolution.
• Digital signal processing (DSP) applications utilizing dynamic performance specifications.
• Industrial control systems interfacing with modern 8-bit or 16-bit microprocessors.

Procurement Notes

Verify the specific suffix 'KR' against the manufacturer's current ordering guide to confirm package type, temperature range, and lead-free status. Ensure compatibility with existing PCB footprints and thermal management requirements. Confirm that the component meets all necessary regulatory standards for the intended deployment environment.

Selection Notes

Select the AD7875KR when a unipolar 0 V to +5 V input range is required. Compare SNR and linearity specifications against system noise floors. Evaluate the interface mode (parallel vs. serial) based on available microprocessor pins and throughput needs. Consider the operating temperature range specified by the suffix letters.

Part Context

The AD7875KR belongs to the AD7870/AD7875/AD7876 family of 12-bit sampling ADCs. While sharing core architecture, the AD7875 is distinguished by its unipolar input range, unlike the bipolar AD7870 (±3 V) and AD7876 (±10 V). The KR suffix typically denotes a plastic SOIC package variant within this product line.

Replacement Considerations

Direct replacements within the same family include AD7870KR (bipolar ±3 V) and AD7876KR (bipolar ±10 V), provided input scaling circuits are modified. Verify pinout compatibility and electrical characteristics before substitution.