Re: led dimmer circuit



i would like a simple circuit that could be used to dim a high
brightness white led for installation inside a bird box for a colour
camera. i don't want to scare the birds by a simple on / off . A
gradule increase in brightness would be good. i have tried a resistor
in series followed by another variable resistor which works to a degree
but there comes a point when the brightness suddenly increases with a
small turn of the pot. could anyone post a simple cicuit please ?

The LED brightness depends on the current. It is easy to make a
voltage to current converter with an opamp:

http://www.allaboutcircuits.com/vol_3/chpt_8/7.html/conversion

But there should also be no problem using resistors. What resistances are
you using (fixed and variable) and is the variable one linear-taper or
audio-taper?


.



Relevant Pages

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  • Re: led dimmer circuit
    ... brightness white led for installation inside a bird box for a colour ... i don't want to scare the birds by a simple on / off. ... gradule increase in brightness would be good. ... in series followed by another variable resistor which works to a degree ...
    (sci.electronics.design)
  • Re: led dimmer circuit
    ... brightness white led for installation inside a bird box for a colour ... gradule increase in brightness would be good. ... in series followed by another variable resistor which works to a degree ... PWM may cause interference when using a digital camera. ...
    (sci.electronics.design)