3.3.1 Isolated Sensing

In some cases, the voltage on the output is too high to divide down reasonably. For these situations, isolated sensing might be a better option. The simplest approach is to use a (linear) optocoupler, which is comprised of an isolated LED and phototransistor. The light from the LED is absorbed by the phototransistor, changing the current through the transistor, which can be used to determine the current flow on the measurement side.