12V & 5V power supply

If you have an old CD-ROM drive. It can play an audio CD alone, a great sound. But it requires a 12V 5V power supply circuit. We have many ways to builds DC power supply for Audio CD-ROM player.

Sometimes you want to save money or want to learn. To create a circuit by yourself.
All circuits are DC voltage regulator. So, you can trust them, low noise.

CD-ROM drive that plays music just by itself

12V 5V power supply circuit using 2N3055 and LM7805
This circuit can deliver DC voltage of 12V and 5V. Which it uses a base parts 2N3055 and Zener Diode-12V. We have to use the input voltage of 15V up. Make can take volt can reach about 15V maintain one’s position voltage be stable 12V well.

And change the integrated circuit LM7805 for regulating about 5V for apply to Digital Circuit general get. For C3-0.1uF filter, the frequency disturbs all well. For other detail, friends see in the circuit.

Note: In this circuit, we use LM309K(ancient) which it is the same as the popular LM7805(Now).

DC power supply 5V and 12V using 2N3055-LM309

Convert two-level DC voltage 5V, 12V
The working principle circuit, start with the AC-line or the electric Current power is fed to this circuit to the transformer T1. Which It will convert AC to lower voltage 9-volts will be switched from AC power into DC with D1-D4 connected to circuit Rex Comment fire Bridge Terminal. (Bridge-Rectifier)

Then, the capacitor C1 will filter to smooth the DC current, which at this point can use the output voltage approximately 12 volts. The output level will flow to diode D5, it acts as to prevent spike voltage through the connection of the output.

Then, the DC current flowing into pin 1 of IC1. Which it acts as the regulated voltage of 5 volts out in pin 3 of IC1, the output level.

The second capacitor C2 and C3 is a current filter to smooth more.

Convert AC to DC voltage two-level, 5V 12V
Convert AC to DC voltage two-level, 5V 12V

Parts you will need
D1,D2,D3,D4,D5: 1N4007, 1000V 1A Diodes
IC1: 7805, 5V DC regulators IC

Electrolytic Capacitors
C1: 470uF 25V
C2: 10uF 25V
C3: 0.1uF 63V Polyester Capacitor
T1: 230V AC primary to 12V,1A secondary transformer

Some want 9V power supply instead of a battery. It is a good idea because it is suitable for low current use.

Also 5V 9V 12V power supply circuits

12V power supply circuits
5v Regulated
Multi voltage regulated dc power supply

Top Linear power supply regulator 5V 5A with 7812 and LM723 When you need a power supply often missed the 3 legs Regulator ICs. But some jobs that apply a high current over 1 Ampere up there, is very difficult. Even if it is 5 amp and 10 amp, but the price is quite high.[…]
5V-12V Multiple Supply Switching regulator by L4970 and L4974A oday take Multiple Supply Switching regulator Circuit. Come to deposit friends keep see in rows think out it can give Voltage supply about 5V 10A and 12V 3.5A. In same circuit by the character of Switching Regulator at use integrated readymade circuit.[…]

What’s more? You can look other power supply circuits: Click Here

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how much AMBER can i take or can i give me from this circuit?



Good Morning Sir,
I saw the circuits on tour website and I want to built, so Just to Know, How to buy the components to make the 2 circuits:
1)Convert Two level DC voltage 5V, 12V
2)Simple AC to DC converter 9V AC to 36V DC
Thank you


how many amps can the above circuit is


We need complete circuit diagram for in put ac 230 volt and out put DC 12vdc13.8vdc amp 15


And diode 2 and 3 what is the number of


470 micro F , may i know about the voltage?


How many ampere does it have?
in DC power supply 5V and 12V using 2N3055-LM309
I need 5v with 3.5A and 12v with 40mA

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