AD7876BQ

Overview

The AD7876BQ is a monolithic 12-bit successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices. It operates from ±5 V power supplies and accepts an analog input voltage range of ±10 V. The device integrates a track-and-hold amplifier, an internal 3 V reference, and versatile interface logic supporting parallel, byte, and serial data formats. Key electrical specifications include a maximum conversion time of 9 μs using the internal clock, a typical power dissipation of 60 mW, and a signal-to-noise ratio of 72 dB at a 10 kHz input frequency. It is housed in a hermetically sealed ceramic dual-in-line package.

Feature Summary

• Integrates a complete 12-bit ADC with a 2 μs track-and-hold amplifier and an on-chip laser-trimmed clock oscillator.
• Features a versatile digital interface allowing selection between single 12-bit parallel words, two 8-bit bytes, or serial data output.
• Includes a factory-trimmed 3 V buried Zener reference capable of sourcing up to 500 μA for external scaling circuits.

Applications

• Data acquisition systems requiring high-speed sampling with bipolar input ranges.
• Digital signal processing applications utilizing DSP-compatible microprocessor interfaces.
• Industrial control environments necessitating hermetically sealed components for radiation or harsh condition resilience.

Procurement Notes

Verify the specific suffix 'Q' against the manufacturer's current ordering guide to confirm the exact temperature grade and package variant, as suffixes define operational limits. Confirm availability status directly with authorized distributors, as this component may be subject to discontinuation or limited production runs. Ensure compliance with relevant environmental regulations applicable to the specific manufacturing lot.

Selection Notes

Select the AD7876BQ when a ±10 V input range is required alongside 12-bit resolution and fast throughput. Compare performance against the AD7870 if a narrower ±3 V range suffices, or the AD7875 for unipolar 0 V to +5 V applications. Consider the package type; the BQ designation indicates a ceramic DIP, which differs electrically and mechanically from plastic SOIC or PLCC variants within the same family.

Part Context

The AD7876BQ belongs to the AD7870/AD7875/AD7876 family of complete 12-bit sampling ADCs. While sharing identical core architecture and interface logic, the family members are distinguished primarily by their analog input voltage ranges: ±3 V for the AD7870, 0 V to +5 V for the AD7875, and ±10 V for the AD7876. The 'BQ' suffix specifically denotes the industrial temperature range and the hermetic ceramic dual-in-line package construction.

Replacement Considerations

Publicly confirmed substitute part numbers for the AD7876BQ are not available in the provided documentation. Replacement requires verifying pin compatibility and electrical equivalence with other hermetic ceramic DIP ADCs from Analog Devices or third-party manufacturers offering equivalent radiation-hardened or military-grade specifications.