Here are 4 simple 12V power supply circuits with output voltages around 12V. First power supply circuit is built with BD139, one zener diode and a few passive components. Each of the schematic is very ...

Diodes whose reverse-breakdown characteristics are controlled precisely during manufacture are called as Zener diodes and are intended specifically for operation in the reverse breakdown mode ...

Normally, when you want a low DC voltage from the AC line, you think about using a transformer of some kind. [RCD66] noticed that an AC monitor meter must have some sort of power supply but had no ...