Texas Instruments ADS1251EVM

Overview

ADS1251EVM from Texas Instruments is an evaluation module designed to demonstrate and accelerate development with the ADS1251 - a 24-bit, delta-sigma analog-to-digital converter (ADC) delivering 19-bit effective resolution at up to 20.8kHz data rate, ±15ppm INL, 1.5ppm rms noise, and differential input architecture. It supports external reference voltages from 0.5V to 5V and operates from a single +5V supply, targeting high-precision measurement in cardiac diagnostics and chromatography systems.

For engineers reviewing the ADS1251EVM datasheet, ADS1251EVM pinout, ADS1251EVM application, or ADS1251EVM equivalent, this module provides validated hardware for rapid prototyping of low-noise, high-resolution ADC interfaces - including clock synchronization, power-down mode verification, and sinc5 digital filter response characterization using real-world sensor signals.

Technical Context

The ADS1251EVM implements the ADS1251 IC in an SO-8 package with full support for its 4th-order delta-sigma modulator, sinc5 digital filter, and 2-wire synchronous serial interface (SCLK/DOUT-DRDY). It enables precise control of system clock (CLK) frequency to tune data output rates from 100Hz to 20.8kHz and configure notch rejection at 50Hz/60Hz via CLK selection per Table I in SBAS184A.

Hardware design includes buffered reference circuitry (REF3040 + OPA350), decoupling capacitors per TI layout guidelines, isolated digital signal paths, and test points for analog inputs (+VIN/–VIN), VREF, CLK, SCLK, and DOUT/DRDY - all aligned with the ADS1251's absolute maximum ratings and thermal limits (–40°C to +85°C).

Key Specifications

Availability

ADS1251EVM is available at Aetrix Electronics and suitable for precision sensor interface validation, medical-grade signal chain development, and industrial process controller prototyping requiring stable component supply and documented reference hardware.

Supply support for ADS1251EVM 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision data acquisition and signal chain solutions.

The ADS1251EVM belongs to TI's high-accuracy delta-sigma ADC evaluation platform family, engineered specifically to simplify adoption of 24-bit converters in applications demanding ultra-low noise, high CMRR (>90dB), and flexible digital filtering - such as portable instrumentation and smart transmitters.

FAQ

What is the primary function of the ADS1251EVM?

The ADS1251EVM is an evaluation module that provides a complete, tested hardware platform for developing and validating systems using the ADS1251 24-bit delta-sigma ADC. It includes all necessary support circuitry - clock generation, buffered reference, decoupling, and test points - enabling immediate characterization of the ADS1251's performance in real-world signal chains without custom PCB design.

Does the ADS1251EVM include the ADS1251 IC?

Yes, the ADS1251EVM integrates the ADS1251U IC in an SO-8 package as its core conversion engine. The module is fully assembled and tested, with the ADS1251 mounted and electrically connected per TI's recommended layout and grounding practices outlined in SBAS184A.

Can the ADS1251EVM be used to evaluate synchronization of multiple ADS1251 devices?

Yes - the ADS1251EVM supports multi-converter synchronization via the SCLK hold-high method defined in the ADS1251 datasheet. By applying a sustained HIGH on SCLK for ≥4 DRDY cycles, users can verify synchronized modulator reset and aligned DOUT/DRDY timing across multiple ADS1251EVM units or mixed configurations.

What reference voltage configuration does the ADS1251EVM use?

The ADS1251EVM implements TI's recommended buffered reference circuit (Figure 2 in SBAS184A): REF3040 precision voltage reference driving an OPA350 op-amp buffer, delivering low-noise, low-impedance 4.096V to the ADS1251's VREF pin. This configuration ensures optimal 1.5ppm noise performance and minimizes reference current-induced errors.

Is the ADS1251EVM compatible with microcontrollers or FPGAs?

Yes - the ADS1251EVM's 2-wire synchronous serial interface (SCLK and DOUT/DRDY) is directly compatible with standard GPIO or SPI peripherals on microcontrollers and FPGAs. Timing parameters (e.g., t6, t7, t8 per Table II) are fully characterized, and the module provides accessible test points for probing and integration into host system firmware.