You can make energy efficient low cost LED lamp using burnt out waste CFL lamp. Normally, only the outside tube of CFL lamps will be burnt and all other components of CFL lamps can be used. If you are an electronic hobbyist you can make use of these components to make a new energy efficient low cost LED lamp.
1) The holder of CFL lamp
2) CFL lamp’s existing PCB
3) Light reflector plastic film
4) General purpose dotted PCB
5) Other elec comp as shown in ckt dgm.
- The elec components are soldered on CFL Lamps existing PCB by drilling holes and by disconnecting unwanted tracks existing on the PCB (Main ckt board).
- 24 numbers of white LEDs are connected in series on a separate PCB with good reflector plastic film as shown in the figure. I have used the inside of biscuit pack cover as a reflector. Do not use the metal reflector, as it will short the LEDs terminals, unless u insulate it.
- Drill two holes on the CFL lamp holder for heat dissipation.
- Use good insulator like cardboard piece in between main ckt board and LED ckt board.
- Place the main ckt board inside the lamp holder and use the binding wire to hold the LED board with lamp holder (as shown in photos).
- 1uF 400V Poly capacitor for high impedance.
- 100Ω & 220Ω 2W resistors to control inrush of current.
- 440kΩ resistor discharges the poly capacitor after switch off.
- 1N4007 diodes full wave rectifier bridge will convert the AC in to DC.
- 470uF 63V electrolytic capacitor will act as reservoir.
- All the LEDs are connected in series across the +ve and –ve terminal of the rectifier bridge as shown in the photo below.
During testing this circuit take extra care because you are dealing with the 230V AC mains. Capacitors will be in charged condition even after you switch off the supply.
Build this circuit with your own risk.