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    circuit for LED using 230VAC 60hz

    help how to draw the circuit for led using 230vac 60hz

    the circuit should applicable for dimmers

    •   Alt5th March 2011, 09:47

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    Re: circuit for LED using 230VAC 60hz

    if you connect a 1Mohm resistor, the led is protected enough with a high resistor



    •   Alt5th March 2011, 10:32

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    Re: circuit for LED using 230VAC 60hz

    but sir its ac so how can i make it not blinking



    •   Alt5th March 2011, 14:38

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    Re: circuit for LED using 230VAC 60hz

    Humans don't perceive a blink rate above ≈40 Hz so it won't appear to blink at 60 Hz.

    This may be the schematic you want: AC-LED. Whenever you apply AC to an LED you need to protect it from reverse voltage with a diode in reverse parallel as shown.

    This application note on transformerless power supplies may also be of use to you: http://ww1.microchip.com/downloads/e...tes/00954A.pdf.
    Last edited by KJ6EAD; 5th March 2011 at 14:59.


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    Re: circuit for LED using 230VAC 60hz

    Quote Originally Posted by bajgik View Post
    if you connect a 1Mohm resistor, the led is protected enough with a high resistor
    If you used a 1Mohm resistor to limit the current, then you are going to create serious inefficiencies in the circuit. You will be dissipating a lot of wasted power through that resistor (I^2*R).



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    Re: circuit for LED using 230VAC 60hz

    An 100 or 120nF X2 rated cap with a series 1000 ohm surge limiting resistor (2W, 500V rated) will limit the current to near 10mA, put the LED in a bridge rectifier, (any 4 diodes with a V>5V and I>50mA will suffice) and this will work fine, for a triac dimmer input, worst case dissipation on the 1000 ohm will be 0.8 watt.
    (for 5mA rms in the LED use 68nF X2 and so on...)

    Regards, Orson Cart.
    Last edited by Orson Cart; 8th March 2011 at 22:15.



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