7812 Based 12 Volt DC Power Supply Circuit

Many electronic projects need 12V clean power for output devices like LCD, graphic LCD and DC motors.

A simple AC to DC converter using 7812 regulator, provides fixed 12V for small devices and general use; also big 100uF capacitor remove big AC ripple from rectified DC.

Then small 0.1uF capacitor remove small ripple from regulated output.

Further, students and beginners use it for learning electronic power basics and also this 7812 Based 12 Volt DC Power Supply Circuit is easy to build.

Circuit Working:

Parts List:

Components	Values	Quantity
Capacitors	Electrolytic 100uF 25V	1
	Ceramic 0.1uF	1
Semiconductors	IC 7812 Voltage Regulator	1
	Transformer 18V AC Secondary	1
	Bridge Rectifier Diode 1N4001	4

In this article transformer give AC voltage to circuit, then a bridge rectifier change this AC into DC, but DC is still not clean.

After that, a big capacitor charge and smooth the DC so ripple become less and then 7812 regulator take this DC and make fixed 12V output.

Even if input go little up or down then to 7812 keep voltage stable.

Further, small capacitor at output remove tiny noise and make DC more clean and finally circuit give steady 12V DC for any small load or device.

How to Build:

To build a 7812 Based 12 Volt DC Power Supply Circuit we need to follow the below steps for connection:

• First, collect all parts shown in the circuit.
• Next, connect transformer pins 2 and 4 to the AC input pins of the bridge rectifier.
• After that, pin 3 of bridge goes to input pin of 7812 IC.
• Then pin 1 of bridge is negative, connect it to ground.
• Now connect input pin of 7812 to positive side of capacitor C1 and then connect negative side of C1 to ground line.
• Also, connect pin 2 of the 7812 to the ground line.
• Further, pin 3 of 7812 is output, this gives 12V DC.
• Finally, connect one end of capacitor C2 0.1uF to the 12V output and connect the other end of C2 to ground.

Conclusion:

Overall, this circuit give simple and steady 12V DC power for many small electronic works, also it changes AC to stable DC for many hobby circuits.

Moreover, its a good project for small circuits needing clean power.