Analog Devices Inc. AD7328BRUZ

Overview

AD7328BRUZ from Analog Devices is an 8-channel, 12-bit plus sign successive approximation ADC with true bipolar input capability, software-selectable ±10 V/±5 V/±2.5 V/0 V to +10 V ranges, 1 MSPS throughput, and integrated 2.5 V reference-designed for industrial data acquisition systems requiring high-accuracy analog monitoring of mixed-polarity sensor signals.

For engineers reviewing the AD7328BRUZ datasheet, AD7328BRUZ pinout, AD7328BRUZ application, or AD7328BRUZ equivalent, this page delivers verified specifications, validated pin functions, confirmed channel sequencing behavior, real-world dynamic performance (76 dB SNR, −80 dB THD), and precise alternative selection guidance for multi-range, high-isolation SAR ADC deployment.

Technical Context

The AD7328BRUZ implements a 13-bit SAR architecture with iCMOS process technology enabling ±16.5 V analog supply operation and true bipolar signal handling without external level-shifting. Its channel sequencer supports independent per-channel configuration for single-ended, true differential, or pseudo-differential modes.

It features a high-speed SPI-/QSPI-/DSP-/MICROWIRE-compatible serial interface with 16-clock-cycle readout, programmable output coding (straight binary or two's complement), and four power modes-including full shutdown (1 µA) and autostandby (1.3 mA at 250 kSPS)-all controlled via dedicated PM bits in the control register.

Key Specifications

Pinout & Package

AD7328BRUZ is housed in a 20-lead TSSOP package (4.4 mm × 6.5 mm, 0.65 mm pitch) with exposed pad for thermal enhancement. Pin layout separates analog (AGND, VIN0–VIN7, VDD/VSS, REFIN/OUT) and digital (DGND, CS, DIN, DOUT, SCLK, VCC, VDRIVE) domains to minimize noise coupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-channel SAR ADC applications.

Compared with AD7329 and AD7327, the AD7328BRUZ uniquely combines 1 MSPS throughput, on-chip temperature sensing, and highest SNR (76 dB) in the AD732x family-making it the only option for high-speed, thermally aware industrial DAQ where per-channel bipolar range flexibility is mandatory.

Availability

AD7328BRUZ is available at Aetrix Electronics and suitable for industrial process control, energy metering, motor drive feedback, and test equipment requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for AD7328BRUZ 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 centers worldwide and a 50+ year heritage in precision data conversion.

The AD7328BRUZ belongs to the AD732x family of software-configurable, multi-range SAR ADCs-engineered specifically for industrial automation systems needing robust bipolar signal acquisition without external signal conditioning.

FAQ

What input voltage ranges does the AD7328BRUZ support, and how are they selected?

The AD7328BRUZ supports four software-selectable input ranges per channel: ±10 V, ±5 V, ±2.5 V, and 0 V to +10 V. Each range is configured independently via the range registers using the serial interface. Selection requires writing to the appropriate range register address (0x01–0x08) with the corresponding 2-bit code. The AD7328BRUZ automatically adjusts full-scale interpretation and internal gain accordingly-no external resistor networks or jumpers are needed.

Does the AD7328BRUZ require an external reference, or does it include an internal one?

The AD7328BRUZ includes a factory-trimmed 2.5 V internal reference with ±10 mV error over temperature and 25 ppm/°C drift. It is enabled by default at power-up. An external 2.5–3.0 V reference can be applied to the REFIN/OUT pin to disable the internal reference-required when operating with ±12 V input range (using 3 V reference). The AD7328BRUZ reference output remains stable under load due to 7 Ω output impedance and supports decoupling with a 680 nF capacitor.

How many analog input configurations does the AD7328BRUZ support, and what are they?

The AD7328BRUZ supports three analog input configurations selectable via the control register's Bit Mode bits: eight single-ended inputs, four true differential pairs (VIN0–VIN1, VIN2–VIN3, etc.), or four/seven pseudo-differential inputs (where one input serves as common-mode reference). True differential mode provides highest CMRR (−79 dB) and best dynamic performance; pseudo-differential offers flexibility for ground-referenced sensors sharing a common return path. All modes operate across all software-selected input ranges.

What power supply voltages does the AD7328BRUZ require, and how do they relate to input range?

The AD7328BRUZ requires three independent supplies: VDD (+12 V to +16.5 V), VSS (−12 V to −16.5 V), and VCC (2.7 V to 5.25 V). Minimum VDD/VSS magnitudes depend on selected input range: ±10 V requires ≥±10 V, ±5 V requires ≥±5 V, and 0 V to +10 V requires VSS ≥ AGND (i.e., ≥0 V). VCC powers the ADC core; full DC accuracy specs apply only at ≥4.75 V. VDRIVE (2.7–5.25 V) sets logic I/O levels and must not exceed VCC by more than 0.3 V.

Can the AD7328BRUZ operate in low-power modes, and how are they controlled?

Yes, the AD7328BRUZ offers four power modes controlled by PM1/PM0 bits in the control register: Normal (31 mW), Autostandby (1.3 mA at 250 kSPS), Autoshutdown (1 µA, wakes on CS), and Full Shutdown (1 µA, wakes on CS or SCLK). Autostandby dynamically powers down between conversions; Autoshutdown enters low-power state after conversion completes and wakes on next CS assertion. These modes are fully software-configurable and retain register settings-no hardware reset is needed to exit low-power states. The AD7328BRUZ achieves fastest wake-up (<25 µs) from full shutdown when using internal reference.