Here is a High power White LED lamp that gives ample light in a room. It is an energy saving lamp and consumes very little power to give sufficient light. The lamp is directly powered from AC hence it is compact and easy to fix inside the switch board box.
The circuit uses 1 Watt White LED as the light source. Luxeon type high watt LEDs are now available. It is rated 3.6 volts and consumes maximum 350 milli amperes current.
1 Watt LED
To get sufficient brightness of the LED, more than 200 mA current is required. The AC power is dropped by three 105K (1uF) AC capacitors to low voltage AC. Three capacitors (C1through C3) are connected in parallel to increase current so around 210 mA current will be available. The low volt AC is then rectified by the bridge comprising D1 through D4 and made ripple free by C4. Since the LED voltage is 3.6 V, Zener diode is used to regulate the DC to a safer level. Capacitor C5 act as a buffer to store current to give maximum brightness to the LED. Resistor R1 removes stored current from the AC capacitors when the circuit is unplugged and resistor R2 protects the circuit from transients and inrush current.
Caution: It is important to note that this circuit can give a lethal shock if handled carelessly. Most points are at mains potential, so that take utmost care while handling. Do not construct this if you are not experienced in handling AC circuits. Do not troubleshoot or test when it is connected to mains.
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Power LED Lamp
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a perfect merging of life science and physical science-congrats!!
Both Biology and Electronics are emerging as One – The Bionics.
Thanks
your circuit designs inspires students who are dreaming to be a successful electronic engineer.. thanks a lot…:D
Thanks
http://dmohankumar.wordpress.com/
Dear Sri. DMK,
Now there are 3,5 and even more wattage bulbs available in the market. can you please give circuit modifications for them too
regards
prasad
Hello Vhhp
Bulbs take large current than High power LED. Brightness is also low when compared to LED. So it is better to use LED.
Dear Sri. DMK, What pieces to change when the main AC is 120V ?
I HAVE A 5X 1W LED IN A BOARD I’M USING THIS CIRCUIT TO TRY OUT BUT I AFRAID THAT THE CIRCUIT WILL NOT SUPPORT ENOUGH CURRENT TO MY BORD, CAN YOU PLEASE HELP OUT? I MEANS NEED TO CHANGE SOME OF THE COMPONENT FROM YOUR CIRCUIT DO YOU HAVE ANY IDEA ? URGENTLY NEED HELP!