12VDC to 9VDC Converter

This is a 12VDC to 9VDC converter circuit. You may use this DC to DC stepdown converter circuit if you have fixed 12V power supply / battery, but you need 9V power supply for your electronic devices.

Scheme Diagram:

12VDC to 9VDC Converter circuit diagram

Components List:

R1________ 560 ohm, resistor
C1________ 1000uF/16V, Electrolytic capacitor
C2________ 100uF/16V, Electrolytic capacitor
C3________ 330nF, Ceramic capacitor
Z1________ 9.1V, 0.4watt zener diode
Q1________ ECG184, NTE184 NPN Transistor


Circuit Notes:

To get a more precise output voltage, replace zener diode Z1 with 10V and R1 with a 1 Kilo ohm potentiometer.
A Coolrib / heatsink for Q1 is optional but recommended for better transformer performance. Simple circuit to power your 9 volt cassette recorder and other stuff.


4 thoughts on “12VDC to 9VDC Converter

  1. bryan

    hi,, can you make diagram for 36vdc to 12vdc?? thanks..

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