High-accuracy ±0.5% current and isolated voltage measurement reference design using 24-bit delta-sigma ADC

This analog front end (AFE) design shows how to connect two or more Σ-Δ ADCs for simultaneous sampling and how to expand the number of input channels to provide maximum flexibility. Precision current measurement is achieved by connecting the AFE to a current transformer (CT) and a Rogowski coil. Likewise, accurate voltage measurements are achieved using resistive voltage dividers without and with isolation amplifiers. The AFE can be configured to measure unipolar or bipolar inputs. The required power is provided onboard. Additionally, diagnostics can be integrated into one design, as shown in TIDA-00810.

characteristic

• ● Precision data acquisition over a wide input range using 4-channel simultaneous sampling 24-bit Σ-Δ ADC
• ● Channel expansion by connecting multiple devices with simultaneous sampling synchronized to a buffered common clock
• ● Current measurements – verify performance using current transformers or Rogowski coils with hardware integrator
• ● Voltage measurement – ​​Verify performance using voltage divider (PD) without and with isolation amplifier (basic or reinforced isolation)