AD7870AQ

Overview

The AD7870AQ is a complete monolithic 12-bit analog-to-digital converter featuring a 2 μs track-and-hold amplifier and an 8 μs successive approximation ADC. It operates from ±5 V power supplies with a typical power dissipation of 60 mW. The device includes an on-chip 3 V buried Zener reference and supports parallel, byte, and serial digital interfaces. It offers a signal-to-noise ratio of 72 dB at a 10 kHz input frequency and a data access time of 57 ns. The industrial temperature range spans from -40°C to +85°C.

Feature Summary

• Integrated 12-bit SAR architecture with internal laser-trimmed clock oscillator
• Versatile interface logic supporting parallel, byte, and serial data formats
• On-chip temperature-compensated 3 V buried Zener reference

Applications

• Data acquisition systems requiring high-speed sampling
• Digital signal processing front-ends
• Industrial control applications

Procurement Notes

Verify the specific suffix AQ against official Analog Devices documentation to confirm the industrial temperature rating and package type. Ensure compatibility with ±5 V supply requirements and check for any obsolete status or lifecycle notices in current manufacturer catalogs before finalizing procurement plans.

Selection Notes

Select this component for applications requiring a single-supply compatible 12-bit resolution with integrated timing and reference circuitry. Consider the ±3 V input range limitation compared to other variants in the family. Evaluate the 57 ns access time against microprocessor bus speeds to ensure proper system synchronization without external wait states.

Part Context

This part belongs to the AD7870/AD7875/AD7876 family of fast, complete 12-bit sampling ADCs. While sharing core architectural features like the SAR converter and track-and-hold amplifier, it differs from siblings such as the AD7875 (unipolar) and AD7876 (±10 V input) primarily through its bipolar ±3 V input specification and industrial temperature grade designation.

Replacement Considerations

Direct substitutes within the same family include the AD7870KPZ or AD7870KNZ, which share identical electrical specifications but may differ in package style or commercial versus industrial temperature ratings. Verify pinout and voltage range compatibility when cross-referencing.