Today, many electronic circuits need DC power, but main supply is AC power, so we must change AC to DC.
Therefore, this Simple 12V Power Supply Circuit with Filter Capacitor is needed, as this circuit gives 12V DC output and current capacity is up to 2A.
This circuit is very simple, easy to make, cost is low and only few components are used.
Moreover, this circuit is good for beginners as it can be used for audio amplifiers.
It is useful for electronics projects and is also good for testing boards and lab work.
Circuit Working:
Parts List:
| Components | Value | Quantity |
|---|---|---|
| Resistor | 1.2k 1/4 watt | 1 |
| Capacitor | Electrolytic 2200uF 25V | 1 |
| Semiconductors | LED any color 5mm 20mA | 1 |
| Diode 1N5402 | 2 | |
| Fuse 1A | 1 | |
| ON / OFF Switch | 1 | |
| Transformer primary 220V AC, secondary 12V-0-12V 2A center Tap | 1 |
First, AC supply is given to the circuit and then the switch S1 turns the circuit ON or OFF.
After that the fuse F1 protects the circuit but if excess current flows then fuse will break.
Next, transformer steps down voltage and it converts 230V AC to 12V-0-12V AC.
Then diodes D1 and D2 act as rectifier and then they convert AC voltage into pulsating DC.
Afterward the capacitor C1 filters the ripple and so the output becomes smooth DC.
Finally, LED shows power ON indication and the output DC voltage is around 17V without load.
Why output is 17V and not 12V?:
Because 12V is RMS value and after rectification the peak voltage increases.
Also, capacitor charges to peak value and therefore output becomes higher than 12V.
Formula with Calculation:
RMS voltage of transformer secondary = 12V
Formula for peak voltage is:
Peak voltage = RMS voltage x 1.414
Peak voltage = 12 x 1.414
Peak voltage = 16.97V
This means AC voltage goes up to 16.97V at its highest point.
Therefore, after rectifier and capacitor voltage becomes near 16.97V value.
How to Build:
To build a Simple 12V Power Supply Circuit with Filter Capacitor following steps are required for connection:
- Start, the circuit connection by collecting all the circuit parts as shown in above diagram.
- Then start with transformer primary pins and connect to AC mains via switch and fuse.
- Secondary pins are connected to 12V, CT and 12V.
- Center tap pin connects to ground line.
- Diode D1 1N5402 anode connects to one 12V pin of transformer.
- Cathode connects to positive output.
- Diode D2 1N5402 anode connects to another 12V pin of transformer.
- Cathode connects to positive output and positive of capacitor C1.
- Capacitor C1 positive pin connects to positive output.
- Negative pin connects to ground.
- LED anode connects to resistor R1 and cathode connects to ground.
- Lastly, resistor R1 one side connects to positive output and other side connects to LED anode.
Conclusion:
To conclude, this Simple 12V Power Supply Circuit with Filter Capacitor is a very useful project.
It is easy to understand and build.
Therefore, beginners can try this circuit easily and also it is good for basic electronics projects.
However, for sensitive circuits voltage regulator is recommended.
Overall, this is a reliable and educational power supply circuit.
References:
12VDC 3500mA filtering, what are voltage regulators and capacitor values [closed]