Hi guys, Today I’m going to discuss a new circuit by me, which is a regulated 220v AC to 5v DC Regulated transformerless power supply using LM7805 and TIP41.The circuit discussed in this article is a bit more than just a few capacitors, diodes, and Zener diodes. So, let’s get started with the materials, then circuit, and concept at the end.”Regulated transformerless power supply circuit.
- C1 -2uf, 400v polyester capacitor
- R1 470-600k resistor
- R2 10R(10 OHMS)
- D5 1N4742A(ZENER)
- C2 470uf,50v
- D6 1N5400
- D7 1N4007
- C3 100nf
- U1 LM7805
- D8 1N4007
- Q1 TIP41
- C4 100uf
- C5 0.01uf
Working of a transformerless power supply Circuit and concept:
The circuit diagram above is quite similar to the small one but the difference is the added extra power regulation stages for understanding the basic transformerless power supply click here. After that rectifier stage, I have added a 4742 Zener diode to regulate output to 12v 1w and added a filter capacitor 470uf, 50v. The LM7805 regulator cant provide that much power with this kind of circuitry so I have used transistor TIP41 to amplify its power to 0.8w as due to 2.2uf c1 earlier it wasn’t capable of providing even 0.8w power, although 7805 can provide 1 A current which is equivalent to 5w but though it was not possible here for the regulator alone due to less backup input power to re
Output capacitor c4 and c5 do the filter and backup wor for output. This circuit is suitable for providing power up to 0.8w-1w max. That can power 20 LEDs of 10 ma or 1 piece of 1 watt LED. The circuit can be dangerous while touching under operation. The circuit is tested by simulation and parameters work quite well.
I hope you liked this circuit, if you have any doubts or suggestions, you can comment them below. Thanks for reading.