AD7865AS-1

Overview

The AD7865AS-1 is a four-channel, simultaneous sampling, fast, 14-bit analog-to-digital converter (ADC) manufactured by Analog Devices Inc. It operates from a single +5 V supply and features four track/hold amplifiers that preserve relative phase information across inputs. The device supports input ranges of ±5 V and ±10 V with overvoltage protection up to ±9 V or ±18 V respectively. Key electrical parameters include a conversion time of 2.4 µs per channel, a maximum throughput of 350 kSPS for a single channel and 100 kSPS for all four channels, 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 simultaneously sampled inputs with dedicated track/hold amplifiers
• Hardware or software selectable channel conversion sequences
• High-speed parallel data interface supporting 3 V logic levels
• Integrated internal 2.5 V reference and on-chip clock oscillator

Applications

• AC motor control systems
• Uninterruptible power supplies
• Industrial power meters and monitors
• Data acquisition systems
• Communications equipment

Procurement Notes

Verify the specific suffix AS-1 confirms the ±5 V and ±10 V bipolar input range and commercial temperature grade (-40°C to +85°C). Ensure the package type matches the required 44-lead Plastic Lead Quad Flatpack (PQFP). Confirm RoHS compliance status if required for the specific manufacturing batch.

Selection Notes

Select the AD7865AS-1 when simultaneous sampling of four channels is required to maintain phase coherence. Choose this model over the -2 or -3 variants if bipolar input signals within ±5 V or ±10 V ranges are present. Consider the 115 mW power consumption and 44-pin PQFP package constraints during system design.

Part Context

The AD7865 series comprises three main variants differentiated by analog input voltage ranges: the -1 for standard industrial bipolar ranges, the -2 for unipolar ranges, and the -3 for ±2.5 V processing. The AD7865AS-1 specifically denotes the commercial temperature grade version with ±5 V and ±10 V input capabilities.

Replacement Considerations

Direct pin-compatible replacements within the same family include the AD7865BS-1, which offers improved accuracy specifications but maintains the same ±5 V and ±10 V input ranges and package.