2 12V to 5V DC converter using Zener diode and transistor

DC to DC converter using Zener diode and transistor jpg

This simple converter uses a zener diode and a transistor to convert 12V dc from a battery to 5V DC with a maximum current of 1A. The circuit is very easy to construct and requires only 3 electronic parts, the resistor, Zener diode and transistor. The transistors is  TIP41C, zener diode is  1N4732A or any zener with the same voltage drop and power. Resistor  is   7ohm 7W and  preferably wire-wound type. This converter is useful in powering devices that uses 5V such as USB powered devices and chargers.
The output voltage is given by the formula :
Vout = Zener voltage + 0.65V , where 0.65V is the base-emitter voltage of the transistor


  1. i thank you so much for your time to post these circuit diograms on here. thanx again ya awsome ;-)