AD7872KRZ

Overview

The AD7872KRZ is a complete monolithic 14-bit successive-approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from ±5 V power supplies and accepts bipolar input signals within the ±3 V range. The device integrates a track-and-hold amplifier, SAR ADC, internal 3 V reference, and laser-trimmed clock oscillator. It supports an 83 kSPS throughput rate with a typical power dissipation of 50 mW. The K version guarantees a minimum signal-to-noise ratio of 80 dB at a 10 kHz input frequency. Data is transmitted via a serial interface using SCLK, SDATA, and SSTRB pins.

Feature Summary

• Integrates a high-speed track-and-hold amplifier capable of acquiring signals to 14-bit accuracy in under 2 μs.
• Features a self-contained, laser-trimmed internal clock that eliminates the need for external timing components.
• Includes a factory-trimmed buried Zener voltage reference outputting 3 V with low temperature coefficient.
• Supports synchronization with digital system clocks via an external CLK input to minimize noise.

Applications

• Digital signal processing systems
• High-speed modem applications
• Speech recognition and synthesis circuits
• Spectrum analysis equipment

Procurement Notes

Verify the ordering suffix 'K' corresponds to the commercial temperature range (0°C to +70°C) and the specific dynamic performance grade (80 dB SNR). Confirm package availability matches the required footprint, as the AD7872 is offered in PDIP, CERDIP, and SOIC variants. Ensure supply chain sources provide original manufacturer documentation to validate component authenticity.

Selection Notes

Select the AD7872KRZ when a serial-only data interface is required, distinguishing it from the parallel-capable AD7871. Choose this variant over the J or A versions if the application demands guaranteed 80 dB SNR performance within the commercial temperature range. Verify that the ±5 V supply rails are available, as the device does not support single-supply operation.

Part Context

The AD7872KRZ belongs to the AD7871/AD7872 family of fast, complete 14-bit sampling ADCs. While the AD7871 provides parallel, byte, and serial interfaces, the AD7872 is restricted to serial output only. Both devices share identical analog performance characteristics and internal architecture, fabricated using Analog Devices' LC2MOS mixed technology process.

Replacement Considerations

The AD7872JRZ serves as a direct functional substitute within the same product family. When replacing the KRZ with the JRZ, verify that the lower SNR specification (79 dB min) meets the system requirements. Ensure the replacement part maintains compatibility with the existing serial communication protocol and physical package constraints.