Analog Devices Inc. AD7190BRUZ

Overview

AD7190BRUZ from Analog Devices is a 24-bit sigma-delta ADC with integrated PGA, designed for high-precision DC and low-frequency AC measurement systems. It delivers 8.5 nV RMS noise at 4.7 Hz (gain = 128), supports up to 4.8 kHz output data rate, features 2 differential or 4 pseudo-differential inputs, and operates across –40°C to +105°C - ideal for weigh scales and strain gauge transducer interfaces.

For engineers reviewing the AD7190BRUZ datasheet, AD7190BRUZ pinout, AD7190BRUZ application, or AD7190BRUZ equivalent, key selection criteria include its 24-bit no-missing-codes resolution, simultaneous 50/60 Hz rejection capability, internal 4.92 MHz clock, 4 general-purpose digital outputs, and automotive-qualified TSSOP-24 package.

Technical Context

The AD7190BRUZ implements a sinc4/sinc3 digital filter architecture with selectable chop mode, enabling programmable trade-offs between noise performance (e.g., 16 noise-free bits @ 2.4 kHz, gain = 128) and settling time. Its on-chip PGA offers gain settings from 1 to 128, and the automatic channel sequencer supports up to four pseudo-differential inputs without external multiplexer control.

It integrates reference detect circuitry, a temperature sensor (±2°C typical accuracy), bridge power-down switch (RON ≤ 10 Ω), and burnout currents (500 nA) for sensor diagnostics. The serial interface is SPI/QSPI/MICROWIRE/DSP-compatible with Schmitt-triggered SCLK and dual-function DOUT/RDY pin supporting both data transfer and conversion-ready signaling.

Key Specifications

Pinout & Package

The AD7190BRUZ is housed in a 24-lead TSSOP package (θJA = 128°C/W), with exposed pad for thermal enhancement and RoHS-compliant finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7177-2BRUZ and ADS1256IDBT, the AD7190BRUZ uniquely balances integrated PGA, simultaneous 50/60 Hz rejection, automotive qualification, and 24-bit metrology-grade linearity - making it optimal for industrial weighing and sensor modules where signal chain simplicity and regulatory compliance are critical.

Availability

AD7190BRUZ is available at Aetrix Electronics and suitable for weigh scales, strain gauge transducers, and PLC analog input modules requiring stable component supply, long-term lifecycle support, and automotive-grade reliability.

Supply support for AD7190BRUZ 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, with design centers and manufacturing facilities worldwide.

The AD7190BRUZ belongs to Analog Devices' precision sigma-delta ADC product line, engineered specifically for high-accuracy industrial and instrumentation applications demanding low noise, high linearity, and robust EMC performance in harsh environments.

FAQ

What is the maximum output data rate supported by the AD7190BRUZ?

The AD7190BRUZ supports an output data rate range of 4.7 Hz to 4.8 kHz. At the upper limit of 4.8 kHz, noise performance degrades to ~12.5 noise-free bits (gain = 128, sinc4 filter, chop disabled), while maintaining full 24-bit no-missing-codes resolution. This makes the AD7190BRUZ suitable for both ultra-low-noise static measurements and moderately fast process monitoring. The AD7190BRUZ achieves this range using either its internal 4.92 MHz clock or an external crystal/clock source.

Does the AD7190BRUZ require an external reference voltage?

No, the AD7190BRUZ does not require an external reference voltage. It supports internal reference operation using AVDD as the reference source (REFIN1(+) = AVDD, REFIN1(−) = AGND), with nominal reference voltage of AVDD (4.75 V to 5.25 V). It also accepts external references from 1 V to AVDD on either REFIN1 or REFIN2 pairs. The AD7190BRUZ includes reference detect circuitry that monitors reference integrity and flags faults via status register bits.

How many analog input channels does the AD7190BRUZ support, and how are they configured?

The AD7190BRUZ supports up to four analog input terminals (AIN1–AIN4) that can be configured as either two fully differential input pairs (AIN1/AIN2 and AIN3/AIN4) or four pseudo-differential inputs referenced to AINCOM. Configuration is controlled via the configuration register. The on-chip channel sequencer automatically cycles through enabled channels, eliminating the need for external multiplexing or timing logic. This flexibility allows the AD7190BRUZ to serve diverse sensor topologies without hardware redesign.

What is the purpose of the BPDSW pin on the AD7190BRUZ?

The BPDSW (Bridge Power-Down Switch) pin on the AD7190BRUZ is an internal low-RON (≤10 Ω) switch that connects to AGND. It is used to power down Wheatstone bridge sensors between conversions, minimizing self-heating errors and improving long-term measurement stability. When activated, BPDSW disconnects the bridge from excitation, reducing thermal drift and power consumption. This feature is especially valuable in high-precision weigh scale and strain gauge applications where thermal equilibrium is critical. The AD7190BRUZ controls BPDSW timing automatically during sequenced conversions.

Is the AD7190BRUZ compatible with standard SPI interfaces?

Yes, the AD7190BRUZ is fully compatible with standard 3-wire SPI interfaces, including QSPI™, MICROWIRE™, and DSP-compatible protocols. It uses CS (active-low chip select), SCLK (with Schmitt-triggered input for noise immunity), DIN (data in), and DOUT/RDY (dual-function data out / ready indicator). The SCLK falling edge clocks data out, and the rising edge latches data in. The AD7190BRUZ supports continuous and non-continuous clock modes, and CS can be hardwired low to simplify interface wiring - making the AD7190BRUZ easy to integrate with microcontrollers, FPGAs, and isolated digital interfaces.