Analog Devices Inc. AD7865AS-3REEL

Overview

AD7865AS-3REEL from Analog Devices is a four-channel, simultaneous-sampling, 14-bit analog-to-digital converter (ADC) with ±2.5 V input range, 2.4 µs conversion time per channel, and integrated track/hold amplifiers-designed for high-fidelity signal acquisition in motor control and power monitoring systems.

For engineers reviewing the AD7865AS-3REEL datasheet, AD7865AS-3REEL pinout, AD7865AS-3REEL application, or AD7865AS-3REEL equivalent, this page delivers verified specifications, validated pin functions, confirmed timing behavior under internal clock operation, and real-world selection guidance for ±2.5 V full-scale signal chain design.

Technical Context

The AD7865AS-3REEL implements a successive approximation ADC architecture with four independent track/hold amplifiers, enabling true simultaneous sampling across all channels to preserve inter-channel phase integrity. Its aperture delay matching is ≤4 ns, supporting coherent multi-channel acquisition for FFT-based analysis.

It operates from a single 5 V supply (±5%), integrates a 2.5 V reference (±20 mV error), and supports both hardware (SL1–SL4) and software (DB0–DB3 register) channel selection. Conversion is initiated by CONVST rising edge, with BUSY indicating sequence completion and EOC signaling individual channel readiness.

Key Specifications

Pinout & Package

AD7865AS-3REEL is housed in a 44-lead Plastic Lead Quad Flatpack (PQFP), 10 mm × 10 mm body, 0.8 mm lead pitch, with exposed thermal pad (S-44 package option).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar simultaneous-sampling ADC applications.

Compared with AD7865AS-3REEL, AD7656ASTZ offers greater resolution and channel count but mandates external reference and lacks ±2.5 V native support, while ADS8588HIPM provides more channels and bits but removes the self-contained parallel interface and internal clock-making AD7865AS-3REEL uniquely suited for compact, low-latency, ±2.5 V–optimized designs.

Availability

AD7865AS-3REEL is available at Aetrix Electronics and suitable for motor control systems, uninterruptible power supplies, industrial power meters, and data acquisition systems requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for AD7865AS-3REEL includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Wilmington, MA, with over 50 years of innovation in precision data conversion and signal conditioning.

The AD7865 product line was engineered specifically for industrial and energy infrastructure applications demanding simultaneous multi-channel acquisition, robust overvoltage tolerance, and deterministic timing-targeting AC motor drives, power quality analyzers, and automated test equipment.

FAQ

What is the input voltage range supported by the AD7865AS-3REEL?

The AD7865AS-3REEL supports a bipolar ±2.5 V analog input range, as specified in the Ordering Guide and confirmed in the Analog Inputs section of the datasheet. This range is fixed for the -3 variant and cannot be reconfigured to ±5 V or 0–5 V without hardware modification or external signal conditioning. The device includes overvoltage protection up to –4 V to +18 V on each input, safeguarding against transient events without affecting conversion accuracy on other channels.

Does the AD7865AS-3REEL include an internal reference, and can it be overdriven?

Yes, the AD7865AS-3REEL integrates a 2.5 V reference with ±20 mV error over temperature, accessible at the VREF pin. It can be overdriven by an external 2.5 V ±5% reference source to improve stability or reduce temperature drift. A 0.1 µF decoupling capacitor is required between VREF and AGND, and the external reference must meet the 10 pF max input capacitance specification to avoid oscillation or settling errors in the AD7865AS-3REEL reference path.

How does the AD7865AS-3REEL handle simultaneous sampling across four channels?

The AD7865AS-3REEL uses four independent track/hold amplifiers, each with ≤4 ns aperture delay matching, to capture analog inputs on VIN1A/VIN1B through VIN4A/VIN4B simultaneously. Upon CONVST rising edge, all four amplifiers enter hold mode at precisely aligned times, preserving relative phase relationships. This enables accurate vector calculations, such as power factor and harmonic phase angles, without interpolation or post-processing correction.

What is the maximum throughput rate achievable with the AD7865AS-3REEL?

The AD7865AS-3REEL achieves 100 kSPS aggregate throughput when converting all four channels, based on 2.4 µs per-channel conversion time and sequential execution. For single-channel operation, maximum throughput is 350 kSPS. These rates assume internal clock operation and proper timing adherence-including minimum 100 ns hold time before next CONVST-and are validated across the –40°C to +85°C operating range for the AS grade.

Can the AD7865AS-3REEL interface directly with 3 V microcontrollers?

Yes, the AD7865AS-3REEL supports direct 3 V logic interfacing via the VDRIVE pin, which powers the DB0–DB13 data outputs, BUSY, EOC, and FRSTDATA signals. When VDRIVE is supplied with 3 V ±10%, the outputs meet TTL-compatible voltage levels (VOH ≥ 2.4 V, VOL ≤ 0.4 V) while maintaining full timing specifications. This eliminates the need for external level shifters in mixed-voltage systems using 3 V processors or DSPs.