This reference design shows an active integrator design that covers wide-input current range for Rogowski Coil with accuracy, linearity, stability and repeatability. The integrator uses a precision amplifier with very-low offset and temperature drift. Two configurations of the integrator are shown. One is for precision measurement with less than 3O-phase error and the other is for fast response time (< 15-ms RC). While the output signal is bipolar, optional level shifting stage can be used when unipolar output is required.
Features
- Active integrator design using low offset and close to zero drift amplifier (OPA2188)
- Integrator output compatible with unipolar or bipolar ADC input range (Example: ADS131A04 with 0-5-V or ±2.5-V input)
- Integrator has been tested for accuracy at 50/60 Hz, repeatability and temperature stability over 25°C ± 35°C
- The integrator operates from a single 5-V DC input with positive and negative voltages for bipolar operation generated on board.