This article for Stabilized Adjustable Power Supply 0-15V/5A Circuit tell us about how to make special power supply circuit, which can give voltage from 0 to 15V.
Also, it can run many electric devices because it give 5 amp current, but one more good thing is this power supply stays stable.
Here, the voltage does not changes much, even if input power is little bit different.
Circuit Working:
Parts List:
| Components | Quantity |
|---|---|
| Resistors (All resistors are 1/4 watt unless specified) | |
| 1k | 4 |
| 10k | 2 |
| R6 (Maximum output current < 5A value not specified) | 1 |
| Potentiometer 10k | 1 |
| Preset 22k | 1 |
| Capacitors | |
| Electrolytic 4700μF 35V, 100μF 25V | 2 each |
| Semiconductors | |
| IC 741 | 1 |
| Transistors 2N2222, 2N3055, BC547 | 1 each |
| Zener Diodes 10V , 5.6V | 1 each |
| Bridge Rectifier 6A4 | 4 |
| Transformer 18V 5A | 1 |
To begin with, the P1 potentiometer controls the power supply and we can adjust the voltage from a few volts up to 15V.
Also, P2 preset control the max limit between 15V and 0V and to find value of R6 use this formula:
R6 = 0.7V / Imax
Imax is the max current
Example: If Imax is 5A then R6 = 0.14Ω.
But when output voltage is low , then current is high like 5A power loss can be big, so it is better to use heatsinks on transistors T1 and T2 to keep them cool.
Formula:
The 2N3055 transistor works in a linear power supply that provides an output voltage from 0 to 15V and a current up to 5A; also 2N3055 acts as an amplifier or pass transistor and helps control the output voltage.
The output voltage Vout set as follows:
Vout = Vref × (1 + R2 / R1)
where:
- Vref is a reference voltage which is usually from Zener diode or stable voltage source.
- R1 and R2 make a voltage divider.
Furthermore, the circuit controls the current by placing a resistor in series with the load and using the voltage drop across the resistor to control the base current of the 2N3055 transistor.
How to Build:
To build a Stabilized Adjustable Power Supply 0-15V/5A Circuit follow the below mentioned connection steps:
How to Connect the Circuit:
- First, connect the input voltage source to LM317 input pin and then ground this pin.
- Next, put R1 between LM317 output and adjust pins.
- Then put R2 between adjust pin and ground.
- After that, connect P1 between adjust pin and ground too.
- Also, connect C1 between adjust pin and ground and connect C2 between output pin and ground.
- Now, put R3 between LM317 output and base of T1 and put R4 between base of T1 and ground.
- Connect T1 collector to LM317 output pin and T1 emitter to ground and now put R5 between T1 collector and base of T2.
- Also, T2 collector connects to LM317 output pin and T2 emitter connects to ground.
- After that, connect C3 between LM317 output and ground.
- Then connect D1 between output pin and adjust pin.
- Finally, P2 goes in parallel with R5 which helps set top voltage limit.
Testing and Changes:
- After circuit is ready then turn ON the power and use multimeter to check output voltage.
- To change voltage, rotate P1 and to set max voltage like 15V or lower then adjust P2.
- Put good heat sinks on T1 and T2 so they stay cool.
Safety Precautions:
- Before turning ON the circuit double check all wires and part values.
- Watch carefully during first test if something is wrong and turn OFF and also be sure about capacitor polarity like positive/negative is correct.
- Avoid short circuits.
Conclusion:
To conclude, this Stabilized Adjustable Power Supply 0–15V/5A Circuit uses a simple design, so always check the component datasheets and follow safety precautions.
Also, if anyone is new to electronics then ask help from someone experienced.
Moreover, this type of power supply works in labs, workshops and testing areas where people need clean and stable voltage to build and test electronic devices.