This LED lamp circuit is made from scrap parts taken from broken LED bulbs making it a simple and cheap way to create an LED light using stuff that would otherwise be thrown away.
In this article, you will find a method to turn a broken CFL light into an energy saving LED light.
The cool thing about this circuit is that it can work directly with 230V AC power so you do not need a transformer, which helps save energy.
It uses a capacitive power supply to control the current allowing five bright LEDs to shine efficiently.
Circuit Working:

Parts List:
Component Type | Value/Specification | Quantity |
---|---|---|
Resistors | 470k 1/4W | 1 |
120Ω 1/2W | 2 | |
Capacitors | PPC 0.47µF 400V | 1 |
Electrolytic 47µF 25V | 1 | |
Semiconductors | 1N4007 Bridge Rectifier | 4 |
Zener Diode 16V 1W | 1 | |
LEDs | White Straw Hat 5mm 30mA | 5 |
The circuit we are talking about has a power supply that uses a capacitor.
After that, there is a bridge rectifier, a smoothing capacitor, a Zener diode to keep the voltage steady and some LEDs that act as the output load.
In this circuit diagram the capacitor C1 can handle up to 400V is the main part that controls the current.
There are also two resistors R2 and R3 that help protect the circuit from sudden surges of current and voltage spikes that could cause problems.
Additionally, resistor R1 helps to discharge capacitor C1 when the circuit is turned off.
The diodes D1 to D4 are arranged in a bridge rectifier, change the alternating current AC voltage into direct current DC.
This means the AC input is turned into a pulsating DC output.
The capacitor C2 is important for smoothing out the rectified DC voltage making the output more stable.
To keep the voltage safe and prevent it from going too high a Zener diode D5 is used for voltage regulation.
Finally, there are five bright LEDs each needing 3V and 30mA connected in series to use the 16V output efficiently.
Each LED drops about 3V so for five LEDs the total voltage needed is 5 × 3V which equals 15V.
This is well within the safe limits set by the Zener diode ensuring everything works properly.
Formulas with Calculations:
Below mentioned are the formulas with calculations for DIY LED Lamp Circuit using Salvaged Parts from Blown LED Bulb:
Current Limiting by Capacitor C1:
The capacitive reactance formula:
Xc = 1 / (2πfC)
where,
C1 = 0.47µF and f = 50Hz:
Xc = 1 / (2 × 3.1416 × 50 × 0.47 × 10⁻⁶)
Xc = 6770Ω
The current through C1:
I = V / Xc
For 230V AC input:
I = 230V / 6770Ω
I = 34mA
Since the LED current requirement is 30mA this current is suitable.
Power Dissipation in Resistors:
For R2 and R3 (120Ω each):
Power = I² × R
P = (0.034)² × 120
P = 0.14W
Using 1/2W resistors ensures safety.
How to Build:
To build a DIY LED Lamp Circuit using Salvaged Parts from Blown LED Bulb following steps need to be followed while assembling and connections:
- Carefully remove the broken glass from the frame.
- Take your time to avoid injuries from sharp edges.
- Once the glass is removed, gently open the assembly to access the internal components.
- Handle it cautiously to prevent further damage.
- Detach the electronic components carefully.
- This may involve unscrewing or unclipping parts, so proceed gently to avoid damage.
- Dispose of the removed components properly following local regulations for hazardous materials.
- Build the circuit on a dot matrix PCB or a 1mm thick laminate sheet.
- If using a laminate sheet, cut a round piece with scissors, ensuring it is large enough for the circuit.
- Plan the circuit layout and mark six evenly spaced holes for the LEDs.
- Use a drill to create the holes selecting a drill bit that fits the LEDs snugly.
- Clean up any rough edges to ensure a smooth fit.
- Apply a small amount of glue to the base of each LED and insert them into the holes.
- Let the glue dry completely for a strong bond.
- Close the assembly carefully, ensuring that no wires touch each other.
- Use cable ties or clips to keep the wiring neat.
- Once everything is in place, connect the assembly to a 230V AC power source.
- Follow all safety precautions and monitor the circuit to ensure it works correctly.
- Now gather all the necessary components mentioned in the above circuit diagram and design your own brightness lamp.
Conclusion:
This DIY LED Lamp Circuit using Salvaged Parts from Blown LED Bulb is a simple and smart way to light up a space while using very few parts.
It does not need a big transformer, which makes it small and affordable.
By using recycled parts it offers a budget friendly and environmentally friendly way to provide light.
This setup is perfect for understanding the basics of changing AC to DC, driving LEDs, and using capacitive power supplies.
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