AD7865BSZ-3

Overview

The AD7865BSZ-3 is a four-channel, simultaneous sampling, 14-bit successive approximation analog-to-digital converter (ADC) manufactured by Analog Devices. It operates from a single +5 V supply and features an internal 2.5 V reference and on-chip clock oscillator. The device provides ±2.5 V bipolar input ranges with overvoltage protection up to ±18 V. Key electrical parameters include a maximum conversion time of 2.4 µs per channel, a track/hold acquisition time of 0.35 µs, and a typical power dissipation of 115 mW in normal mode. It utilizes a high-speed parallel interface compatible with 3 V processors.

Feature Summary

• Four independent track/hold amplifiers enable true simultaneous sampling across all channels to preserve relative phase information.
• Hardware or software selectable channel sequences allow conversion of any subset of the four inputs to maximize throughput rates.
• Integrated signal conditioning circuitry supports multiple input voltage ranges including ±2.5 V, ±5 V, ±10 V, and unipolar options.
• High-speed parallel data bus facilitates direct interfacing with microprocessors, microcontrollers, and DSPs.

Applications

• AC Motor Control
• Uninterruptible Power Supplies
• Industrial Power Meters/Monitors
• Data Acquisition Systems

Procurement Notes

Verify the specific suffix 'B' indicates improved accuracy specifications compared to the 'A' version. Confirm the '-3' suffix corresponds to the ±2.5 V input range requirement for your application. Ensure the PQFP-44 package dimensions match your PCB footprint constraints. Check for RoHS compliance status if required by your manufacturing standards.

Selection Notes

Select this component when simultaneous multi-channel sampling is critical to maintain signal phase relationships. The AD7865BSZ-3 is appropriate for applications requiring ±2.5 V input ranges with higher linearity accuracy than the standard A-version. Consider the 115 mW power consumption against thermal management capabilities in enclosed designs.

Part Context

This part belongs to the AD7865 family of fast, low-power ADCs. The BSZ-3 variant specifically denotes the B-grade accuracy level within the Plastic Lead Quad Flatpack (PQFP) package. It shares the same functional architecture as the ASZ-3 but offers tighter gain error and nonlinearity specifications.

Replacement Considerations

The AD7865ASZ-3 serves as a lower-cost alternative with slightly relaxed accuracy specifications. For unipolar applications, the AD7865BSZ-2 offers 0 V to 5 V ranges. Bipolar ±5 V or ±10 V requirements necessitate the AD7865BSZ-1 variant.