The top circuit, in the diagram above, is a half-wave rectifier and you can see the circuit’s effects on a sinusoidal signal. What is the bottom circuit and how would it effect a sinusoidal input?

This circuit was designed to meet a medical application’s requirement to drive a laser diode with reasonable precision and a minimum of components and footprint (the device is now in clinical trials).

When looking across the discrete components in your electronic armory, it is easy to overlook the humble diode. After all, one can be forgiven for the conclusion that the everyday version of this ...