In this post we will talk about a 12V Regulated Power Supply Circuit
It give steady 12V output using few parts.
This circuit is good for small projects which need clean power and easy to build and use.
What is 12V Regulated Power Supply Circuit:
It is an electric circuit that changes moving input voltage into steady 12V output.
This circuit is used to give power to many electronic parts that need 12V DC all time.
Even if input voltage or load changes but output will still stay same 12V because of regulation.
Circuit Working:
Parts List:
| Component | Quantity |
|---|---|
| Resistors | |
| 10Ω 1W | 1 |
| 1k 0.5W | 1 |
| 560Ω 0.5W | 1 |
| Capacitors | |
| Electrolytic 470µF 16V | 1 |
| Electrolytic 100µF 16V | 2 |
| Semiconductors | |
| Bridge Rectifier 1N4007 | 4 |
| Zener Diode 12V 1W | 1 |
| LED Green 3.3V 20mA | 1 |
| Transistor TIP35C | 1 |
| Transformer 0-15V | 1 |
Zener diode is main part in this circuit it work in reverse side which is in Zener breakdown.
Transistor Q1 work like changeable resistor.
It change its resistance when base current change and Zener diode gives fixed voltage to control this.
Output voltage (Vout) we get using this formula:
Vout = Vz − VBE
where:
- Vout is output voltage
- Vz is Zener voltage
- VBE is voltage between base and emitter of transistor
This formula help to know how voltage changes in circuit with transistor and how VBE drop affect output voltage.
It is important to learn this for making circuit where exact voltage is needed.
Advantages and Disadvantages:
Advantages:
- This circuit is easy and cheap way to control voltage.
- Its Output voltage stay always stable.
- It is good for projects that need more current.
Disadvantages:
- This circuits are only good for low or medium power use.
- They are not as efficient as other ways to control voltage.
How to Build:
Follow the below mentioned construction steps for building a 12V Regulated Power Supply Circuit:
- Start with step down transformer to get AC input which is at least 15V.
- Use bridge rectifier or 4 diodes 1N4007 in bridge shape to change AC to DC.
- Then put capacitor C1 to filter and smooth the DC voltage.
- Add LED to show power is ON.
- Connect resistor R3 and capacitor C2 in series from plus to minus side to give VBC to transistor Q1.
- Put 12V Zener diode ZD1 in reverse way to base of transistor Q1.
- When Zener breaks down it controls base of transistor and gives fixed output voltage.
- If we change Zener diode value we can get different output voltage for different needs.
Components Functions:
- Zener Diode ZD1
- Gives fixed voltage (Vz) to circuit.
- Works in Zener breakdown mode.
- Important part to keep voltage stable.
Transistor Q1 – TIP35C
- It is NPN BJT transistor.
- Used for amplifier and switch work.
- Can handle big current and low heat loss.
- Good for medium power projects.
- Comes in TO220 plastic case which is easy to cool and handle.
Conclusion:
12V Regulated Power Supply Circuit is cheap and good way to get steady voltage in electronics.
If person understand basic idea and how to build it they can change circuit for different voltage it needs.
Need to choose right Zener diode and transistor to give wanted voltage and handle enough current.
This circuit can be used in many projects but for big or heavy power use it has some limits in efficiency and power.