Analog Devices Inc. AD7472AR

Overview

AD7472AR from Analog Devices is a 12-bit, 1.5 MSPS successive approximation analog-to-digital converter (ADC) with parallel interface, operating from a single 2.7 V to 5.25 V supply and consuming only 4.5 mW at 3 V. It features 12-bit resolution, 70 dB typical SNR at 500 kHz input, and 24-lead SOIC packaging. It is used in high-speed data acquisition systems requiring low power and precise timing control via CONVST and BUSY signals.

For engineers reviewing the AD7472AR datasheet, AD7472AR pinout, AD7472AR application, or AD7472AR equivalent, key selection considerations include its 12-bit resolution, 1.5 MSPS throughput at 5 V, 14-cycle conversion time, external 2.5 V reference requirement, and SOIC-24 package with separate analog/digital grounds and VDRIVE for level-shifted outputs.

Technical Context

The AD7472AR implements a standard successive approximation register (SAR) architecture with no pipeline delay, enabling deterministic latency: conversion completes 531.66 ns after the falling edge of CONVST at 26 MHz clock. Its track-and-hold amplifier supports full-power bandwidth up to 20 MHz and acquires input within 135 ns after BUSY goes low.

It uses dual-supply separation (AVDD/DVDD) with strict ±0.3 V inter-rail tolerance and independent AGND/DGND references. Output drivers are powered by VDRIVE (2.7–5.25 V), allowing digital interface to 3 V logic while AVDD operates at 5 V for optimal dynamic performance.

Key Specifications

Pinout & Package

AD7472AR is housed in a 24-lead SOIC (R-24) package with gull-wing leads, 75°C/W junction-to-ambient thermal resistance, and Pb-free finish compliant with RoHS. Pin layout separates analog (AVDD, AGND, VIN, REF IN) and digital (DVDD, DGND, CS, RD, DB0–DB11) domains to minimize coupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit parallel SAR ADC applications.

Compared with AD7472BR, AD7472AR trades guaranteed 12-bit monotonicity for cost-sensitive industrial use; compared with ADS7822U, it delivers 6× throughput and parallel interface efficiency but requires more PCB area and design effort for bus routing and timing.

Availability

AD7472AR is available at Aetrix Electronics and suitable for industrial data acquisition, medical instrumentation, communications test equipment, and automotive sensor interface applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for AD7472AR 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Norwood, MA, with design and manufacturing expertise spanning over 50 years.

The AD7472AR belongs to Analog Devices' high-speed SAR ADC product line, engineered for applications demanding deterministic latency, low power at high throughput, and robust analog performance in industrial and instrumentation environments.

FAQ

What is the maximum clock frequency supported by the AD7472AR?

The AD7472AR supports a maximum CLK IN frequency of 26 MHz at 5 V and 20 MHz at 3 V, as specified for A and B versions. This clock determines conversion time (14 cycles) and achievable throughput (1.5 MSPS at 5 V). Exceeding these frequencies may cause timing violations or reduced AC performance.

Does the AD7472AR require an external reference voltage?

Yes, the AD7472AR requires an external 2.5 V reference applied to the REF IN pin, with ±1% tolerance for specified performance. The device does not include an internal reference; using a precision external reference directly impacts offset, gain, and full-scale accuracy.

How does the VDRIVE pin function in the AD7472AR?

The VDRIVE pin supplies power to the AD7472AR's digital output drivers independently of DVDD. This allows the analog core (AVDD) and digital logic (DVDD) to operate at 5 V for optimal performance while driving 3 V logic levels on DB0–DB11 - eliminating external level shifters in mixed-voltage systems.

What is the purpose of the BUSY signal in the AD7472AR?

The BUSY signal is an active-high open-drain output that goes high at the start of conversion and returns low 531.66 ns after the falling edge of CONVST (at 26 MHz). It indicates conversion completion and synchronizes read operations with CS and RD, ensuring data validity before latching.

Can the AD7472AR operate with separate analog and digital ground planes?

Yes, the AD7472AR has dedicated AGND and DGND pins, but they must be held within ±0.3 V of each other at all times - even during transients - to prevent distortion or latch-up. Best practice is a single-point star ground connection near the device with separate copper pours.