Voltage ranges - BelaPlatform/Bela GitHub Wiki

Moved to learn.bela.io/using-bela/about-bela/bela-hardware/#voltage-levels

Absolute maximum ratings:

  • Audio input/output: 3.3Vpp
  • Analog input/output: 0V to 5V
  • Digital input/output: 0V to 3.3V

Real-world voltages and their digital counterparts in Bela:

  • audio input input range is 1.8Vpp when the PGA is 0dB. This maps to values between -1 and 1 when using audioRead().
  • the headphone out is 2.6Vpp AC coupled when the heapdhone out level is set to 0dB. This maps to value between -1 and 1 when using audioWrite().
  • the hot(+) signal at the line output (unpopulated pads on J9) is 1.8Vpp DC coupled with a DC offset of 1.3V. So audioWrite(context, n, ch, 1) gives 2.2V, audioWrite(context, n, ch, 0) gives 1.3V, audioWrite(context, n, ch, -1) gives 0.4V.
  • the analog inputs have a range of 0V to 4.096V. This maps to values between 0 and 1 when using analogRead()
  • the analog outputs have a range of 0V to 5V. This maps to values between 0 and 1 when using analogWrite()
  • the digital outputs have a range of 0 to 3.3V. using digitalWrite(context, n, ch, 0) you will get 0V, when using digitalWrite(context, n, ch, 1) you will get 3.3V.