This reference design demonstrates bandwidth-optimized analog front end (AFE) and real-time FIR implementation using low power to capture broadband frequency spectrum in any waveform. An operational amplifier in each signal path is chosen based on the gain, signal bandwidth, low noise and close to the rail swing requirements while consuming low power. The waveform is processed in real-time both in frequency and time domain using a mixed signal ultra-low power microprocessor with a built-in vector math engine.
Features
- AFE for effective passing both low frequency and high frequency while suppressing signal noise
- Capturing frequency content up to 100 kHz in frequency domain by sampling the signal using 12-bit SAR ADC at 200 ksps and performing real-time FIR filter in MSP430 using low energy accelerator (LEA) frequency domain by sampling the signal using 12-bit SAR ADC at 200 ksps and performing real-time FIR filter in MSP430 using low energy accelerator
- High frequency time domain analysis:
- Capturing arc signatures up to 3MHz using internal comparator of MSP430
- Noise capture up to 10MHz using external comparator
- IQ requirement of 10 mA is derived from single-phase AC supply of 85 Vrms to 270 Vrms with capability of powering up to 100 mA
- Compatible with various sensors like shunt, CT or Rogowski coil