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WIP

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1. Basic theory of digital measurements
2. Measurement errors
   1. Physical measurement errors
   2. Time-domain errors
   3. Digital domain errors

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Basic theory of digital measurements

Measurement errors

Physical measurement errors

• shunt resistor value offset
• shunt resistor temperature and current dependence
• amplifier input offset voltage
• ADC errors
  • DNL
  • INL
  • Gain error
  • Offset error
  • Quantization error
  • Clipping
  • Noise
• Reference errors

Time-domain errors

• Attenuation at higher frequencies
• Simultaneity and sampling jitter
• Aliasing

Digital domain errors

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• Assumptions about averaging

• LUT calculation errors

• Latency

  • ADC sampling time (1μs)
  • Firmware buffering (0.4ms)
  • USB buffering (1-10ms)
  • Client-side buffering (1-10ms)
  • Client-side processing and visualization (16-33ms)

• Other errors

  • Correcting for voltage drop
  • INA216A1 shunt amplifier supply current

• USB sensor manual - 2016.pdf

• pac1933 datasheet: https://ww1.microchip.com/downloads/aemDocuments/documents/OTH/ProductDocuments/DataSheets/PAC1931-Family-Data-Sheet-DS20005850E.pdf