Analogue front end targets power monitoring applications

The ADC’s wide dynamic range, scalable data rates up to 64 kSPS, and internal fault detect monitors make the ADS131E08S suitable for smart grid and other industrial power monitoring, control, and protection applications.

The AFE incorporates the signal chain with a 24-bit, delta-sigma ADC; built-in programmable gain amplifiers (PGAs); an internal reference; and an internal oscillator on a single 10mm² chip.

The device takes advantage of its eight true high-impedance differential inputs to interface directly with a resistor-divider network or a voltage transformer to measure line voltage, or to a current transformer or Rogowski coil to measure line current.

The ADS131E08S has an individual input multiplexer per channel that engineers can connect to the internally generated signals for test, temperature, and fault detection.

The device has integrated comparators to detect out-of-range conditions on the input signals by comparing the input voltage against a threshold voltage set by a three-bit digital-to-analog converter (DAC) based off the analog power supply.

A performance demonstration kit, also available from Mouser, provides hardware and software for evaluating the ADS131E08S AFE. The kit includes the ADS131E08SEVM evaluation board and a TI MMB0 modular evaluation motherboard, and provides built-in analysis tools — including oscilloscope, fast Fourier transform (FFT), and histogram displays — as well as flexible input configurations and the ability to export data.