Analog Devices Inc. EVAL-AD7191EBZ

Overview

EVAL-AD7191EBZ from Analog Devices is an evaluation board designed exclusively for the AD7191 pin-programmable, ultralow noise, 24-bit sigma-delta ADC. It supports standalone battery-powered operation with LCD display, USB-connected PC software control, and flexible analog front-end interfacing for bridge sensor applications including weigh scales and precision instrumentation.

For engineers reviewing the EVAL-AD7191EBZ datasheet, EVAL-AD7191EBZ pinout, EVAL-AD7191EBZ application, or EVAL-AD7191EBZ equivalent, this board enables rapid validation of AD7191 performance in low-frequency, high-resolution measurement systems - particularly where PGA gain (up to 128), 10 Hz output data rate, external reference support (ADR421), and dual differential inputs (AIN1/AIN2, AIN3/AIN4) are critical selection criteria.

Technical Context

The EVAL-AD7191EBZ implements a complete hardware interface for the AD7191, integrating on-board voltage regulators (ADP3303ARZ-5 and ADP3303ARZ-3.3), a Cypress CY7C68013A-56LFXC USB microcontroller, and an ADR421BRZ precision 2.5 V reference. It supports three power modes: USB 5 V, 9 V battery (regulated to 5 V), and external DC input via screw terminal J10.

Hardware configuration is managed via DIP switch S6 (ODR, gain, channel, clock source), header links (J1 for supply selection, J3 for reference/analog routing), and SMB connectors (REF+, REF−, AIN1, AIN2, MCLK) enabling precise signal injection and noise testing per UG-280 Figures 2–5. The board also provides direct load cell interface through 8-pin header J4 with excitation, sense, and output routing.

Key Specifications

Availability

EVAL-AD7191EBZ is available at Aetrix Electronics and suitable for precision sensor evaluation, industrial weigh scale prototyping, and low-noise instrumentation development requiring stable component supply, traceable sourcing, and long-term lifecycle support.

Supply support for EVAL-AD7191EBZ 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.

The EVAL-AD7191EBZ belongs to Analog Devices' precision data acquisition evaluation platform family, engineered to accelerate design-in of ultralow-noise, high-resolution ADCs for bridge-based sensing and industrial process monitoring.

FAQ

What is the primary function of the EVAL-AD7191EBZ?

The EVAL-AD7191EBZ is a dedicated evaluation board for the AD7191 24-bit sigma-delta ADC. It provides full hardware and software infrastructure - including USB interface, LCD display, on-board reference, configurable power options, and load cell connectivity - to validate the AD7191's performance in ultralow-noise, low-frequency measurement applications without requiring custom PCB development. The EVAL-AD7191EBZ enables immediate functional testing and parameter optimization out of the box.

Does the EVAL-AD7191EBZ support standalone operation without a PC?

Yes, the EVAL-AD7191EBZ supports fully standalone operation using a 9 V battery or external 9 V DC supply. In this mode, it runs a built-in weigh scale demonstration that reads conversions from the AD7191, applies user-calibrated offset and full-scale coefficients, and displays real-time weight on the onboard LCD. Calibration is performed using four tactile buttons beneath the display, and all configuration is handled by the on-board microcontroller - no PC connection is required for basic evaluation of the EVAL-AD7191EBZ.

How is the AD7191 configured on the EVAL-AD7191EBZ?

The AD7191 on the EVAL-AD7191EBZ is configured via 8-position DIP switch S6, which sets output data rate (e.g., 10 Hz), PGA gain (e.g., 128), active channel (AIN1–AIN2 or AIN3–AIN4), clock source, and temperature sensor enable. Switch positions directly map to AD7191 pin states (ODR2, ODR1, CLKSEL, PGA1, PGA2, CHAN, TEMP), and the board's PC software reflects these settings in real time. This eliminates register-level programming during initial evaluation of the EVAL-AD7191EBZ.

Can the EVAL-AD7191EBZ be used with custom sensor circuits?

Yes, the EVAL-AD7191EBZ supports integration with custom sensor designs. Header J2 allows disconnection of the on-board microcontroller, enabling direct SPI interfacing between an external host MCU and the AD7191. Additionally, analog inputs (AIN1/AIN2), reference pins (REF+/REF−), and clock input (MCLK) are accessible via SMB BNC connectors, while header J4 provides standardized load cell routing. This modular architecture lets users repurpose the EVAL-AD7191EBZ's analog section as a ready-to-use front end for proprietary sensor modules.

What software tools accompany the EVAL-AD7191EBZ?

The EVAL-AD7191EBZ ships with Windows-based PC software that provides graphical real-time data visualization, configurable sampling (continuous or defined set), noise analysis (rms, peak-to-peak), WeighScale Demo, Low Noise Quick Test, and User Units Setup for system calibration. Data can be exported to Excel or MathCAD for further analysis. All software functionality is tightly coupled to the EVAL-AD7191EBZ hardware - including automatic detection of switch S6 settings and dynamic update of ADC configuration parameters - ensuring accurate, repeatable evaluation of the EVAL-AD7191EBZ.