Analog Devices Inc. AD7732BRUZ

Overview

AD7732BRUZ from Analog Devices is a 24-bit sigma-delta analog-to-digital converter with two fully differential input channels, ±10 V input range, 18-bit peak-to-peak resolution at 500 Hz, on-chip per-channel system calibration, and 3-wire SPI-compatible serial interface. It operates from a single 5 V analog supply and supports industrial process control signal acquisition where high channel-switching throughput and bipolar voltage measurement are required.

For engineers reviewing the AD7732BRUZ datasheet, AD7732BRUZ pinout, AD7732BRUZ application, or AD7732BRUZ equivalent, key selection considerations include its 2-channel differential architecture, ±16.5 V overvoltage tolerance without adjacent channel crosstalk, 110 dB channel-to-channel isolation, programmable conversion time (372–12.2 kHz), and extended industrial temperature range (–40°C to +105°C).

Technical Context

The AD7732BRUZ implements a 24-bit sigma-delta ADC core with configurable filter word (FW) and chopping enable/disable modes. Its dual differential input multiplexer feeds into a shared modulator and digital filter, enabling fast channel switching with guaranteed 500 μs total conversion time at 2 kHz rate in 16-bit p-p mode.

It integrates on-chip reference detect, per-channel zero-scale and full-scale calibration registers, and a flexible I/O port (P0/P1) with analog-supply-referenced logic levels. The analog front end accepts common-mode voltages from 200 mV to AVDD – 300 mV and tolerates ±50 V absolute input voltage while maintaining ±16.5 V overvoltage immunity across channels.

Key Specifications

Pinout & Package

AD7732BRUZ is housed in a 28-lead thin shrink small outline package (TSSOP) with exposed pad for thermal performance. Pin layout supports compact PCB routing and mixed-signal isolation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-precision, multi-channel sigma-delta ADC applications.

Compared with AD7734BRUZ and AD7738BRUZ, the AD7732BRUZ delivers optimal trade-off of differential input integrity, ±16.5 V fault tolerance, and minimal external components for industrial ±10 V signal chains-making it the preferred choice for PLC analog input modules and high-isolation multiplexed acquisition.

Availability

AD7732BRUZ is available at Aetrix Electronics and suitable for industrial instrumentation, process control systems, and programmable logic controller (PLC) analog input modules requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD7732BRUZ 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 Norwood, MA.

The AD7732BRUZ belongs to Analog Devices' precision sigma-delta ADC product line, engineered specifically for high-accuracy industrial data acquisition where channel isolation, overvoltage resilience, and on-chip calibration are critical.

FAQ

What is the maximum analog input voltage the AD7732BRUZ can tolerate without damage?

The AD7732BRUZ has an absolute maximum rating of ±50 V on AIN pins relative to AGND. However, for guaranteed specification compliance and no degradation of adjacent channel performance, the device supports up to ±16.5 V overvoltage on one channel while maintaining 110 dB channel-to-channel isolation. This overvoltage tolerance applies with nominal BIAS voltage of +2.5 V and proper configuration of RA–RD pins.

Does the AD7732BRUZ require an external voltage reference?

Yes, the AD7732BRUZ requires an external precision voltage reference applied across REFIN(+) and REFIN(–). It is specified for 2.475–2.525 V input, and includes a "No-Reference" detection feature that sets the NOREF bit in the channel status register if the reference falls below 0.5 V. The part does not contain an internal reference and cannot operate without an external reference source.

How does chopping affect the performance of the AD7732BRUZ?

Enabling chopping (CHOP = 1) reduces offset drift to ±2.5 μV/°C and improves integral nonlinearity to ±0.0003% FSR, but limits maximum output data rate to 12.2 kHz. Disabling chopping (CHOP = 0) increases maximum rate to 15.4 kHz and maintains 24-bit no-missing-codes performance, though offset drift rises to ±25 μV/°C. Chopping mode is selected per channel via the mode register.

Can the AD7732BRUZ perform simultaneous sampling on both channels?

No, the AD7732BRUZ does not support true simultaneous sampling. It uses a single sigma-delta modulator with a dual-channel multiplexer, enabling rapid sequential sampling with 500 μs total conversion time at 2 kHz channel-switching rate. While not simultaneous, this architecture achieves effective interleaved acquisition suitable for most multiplexed industrial applications where inter-channel phase skew is not critical.

What digital interface protocols is the AD7732BRUZ compatible with?

The AD7732BRUZ supports 3-wire serial communication compatible with SPI™, QSPI™, MICROWIRE™, and DSP interfaces. All logic inputs (SCLK, CS, DIN, RESET, SYNC/P1, P0) are Schmitt-triggered for noise immunity. The interface operates with either 3 V or 5 V DVDD and supports frame synchronization via CS or SYNC/P1 pin, making it interoperable with most microcontrollers and digital signal processors without level-shifting.