This is a constant current source, perfect to test the functionallity of 0.02A LEDs.
Old description (wrong):
This is a circuit made for a project I build. I want to make an infrared LED flashlight. The problem is, that LEDs change their resistance, when you shine light on them. Infrared LEDs are even more sensitive. I burned 3 of them just by switching the light on. So, this circuit prevents it from burning.
