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12Vdc. operated white led torch

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zsolt1

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hi,
I played with some white led's (super bright ones) and discovered that they can illuminate quite well .... take a look & improve something .

-what about using a high efficiency dc-dc step down converter insted of the LM317 series regulator ?
-and regarding the light spectrum , how to replace some white led's with other colored led's, in order to obtain a rich spectral composition ?

best regards
Zsolt
 

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Last edited:

hi,
I played with some white led's (super bright ones) and discovered that they can illuminate quite well .... take a look & improve something .

-what about using a high efficiency dc-dc step down converter insted of the LM317 series regulator ?
-and regarding the light spectrum , how to replace some white led's with other colored led's, in order to obtain a rich spectral composition ?

best regards
Zsolt

I guess,
- high efficiency dc-dc conveter will improve power efficiency and not brightness of LEDs . It will have little or no impact on brightness of LEDs as illumination mainly depends on current flowing through it. If current is switched then only illumination will be affected. There is no or very little difference in current profile of Linear regulator and DC-DC for LED load which is similar to resistive load.
 

I guess,
- high efficiency dc-dc conveter will improve power efficiency and not brightness of LEDs . It will have little or no impact on brightness of LEDs as illumination mainly depends on current flowing through it. If current is switched then only illumination will be affected. There is no or very little difference in current profile of Linear regulator and DC-DC for LED load which is similar to resistive load.

totally agree!

At 12V power supply of the circuit :
- i have 2 x 0.06 = 0.12 W power lost on the LM317 , as heet, so with the present configuration the circuit's efficiency is (0.6/0.72)x100 = 83.3 %

So with the high efficiency dc-dc converter the efficiency would be : ... ?? (how much ?? )
does it worth it ?

hehe ... that's all about engineering ;-)

Ps: best wishes for the next year for everyone !
 

totally agree!

At 12V power supply of the circuit :
- i have 2 x 0.06 = 0.12 W power lost on the LM317 , as heet, so with the present configuration the circuit's efficiency is (0.6/0.72)x100 = 83.3 %

So with the high efficiency dc-dc converter the efficiency would be : ... ?? (how much ?? )
does it worth it ?

hehe ... that's all about engineering ;-)

Ps: best wishes for the next year for everyone !

Then it looks LM317 is good solution for your circuit! I think, DC-DC may not give more benifit other than size ..Also, you must be aware of DC-DC pros and cons..It does not seem to be worth for your circuit...

Happy New Year to All!!!
 

other opinions?
what about the aspects regarding the white light of the diodes? (for example i consider white light to be a "cold" light ... eyes get tired....)
 

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