Sanjiv Dutta saved some money when he decided to make this LED Based Handycam Light instead of going to the store and buying one. It looks very bright and based on the pictures on his site (scroll to the bottom) it seems to work very well!
“I have come with a naive solution, but a working one. I put resistors to drop the supply voltage when needed, by means of a 3 position switch as described in the Ckt. below.
Lets see the current & voltage delivered to the LEDs that way:-
It was found that , when voltage across LED = 3 v, current consumption = 20 mA approx.
And for 3.1.v, it becomes about 22 mA.
For 20 LEDs, that is = 440 mA
Hence, if Supply voltage is 3.6 v, voltage drop needed across the resistor = 0.5 v.
Again, when Supply voltage drops to 3.3 v, voltage drop needed across the resistor = 0.2 v.
We do not need any resistors when Supply voltage further drops to 3.1 v or 3 v.
Thus we found out the required resistor values.”
September 7th, 2006
Site is down
are those 10mm LEDS?
September 7th, 2006
cool.. will try this out!
September 7th, 2006
LOL.. nice
September 7th, 2006
Do you have schematics for this?
September 8th, 2006
Yes, 10 mm. I have schematics, but withdrawn later to hide from some unthankful greedy ppl.
Kevin pl. gimme your e-mail id I wil sent it directly.
Have u anyway saw the whole article on geocities.com/san011070/site/LED_light.htm ?
Bye…& Thx
September 8th, 2006
Sorry, I mean http://geocities.com/san011070/code/LED_light.htm
April 13th, 2007
led? not using IR? I`m intrested in using ir, and take out ir pass filter from yhe camera.
please email me,i want to know :=)