Learning BeagleBone Python Programming

ADC

The BeagleBone has 7 available inputs to its analog-to-digital converter (refer to Appendix A, The BeagleBone Black Pinout to see which pins support analog inputs). The ADC can approximate voltages at each of these pins between 0 V and 1.8 V. As mentioned in Chapter 1, Before We Begin, putting voltages greater than 1.8 V on any of the ADC's input pins will damage your BeagleBone. That doesn't mean we can't measure higher voltages with it, we just need some external circuitry to do so.

Voltage divider

The simplest method for measuring voltages greater than 1.8 V is to use a voltage divider, which is simply composed of two resistors in a series between your voltage source and 0 V, with the output being the node between them:

The output voltage ...