My little dilemma with LEDs shining through a label

Started by PeterPan, May 24, 2015, 08:58:28 PM

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Jdansti

Quote from: armdnrdy on May 25, 2015, 02:59:07 PM
This is from the OPs first post.

"I've used small 3MM low current (2ma) LEDs like the Vishay TLLR4401 in may many project, whenever I had a low current requirement"

If I recall correctly...the OP had another thread going that included pictures and explained what this thing is.
It is a portable switcher. Battery powered. This is why he wants to use low current LEDs.
It doesn't matter where in the circuit the LEDs are connected...they will draw the same amount of current.

Maybe, but I was going by this:

The brighter LEDs you mentioned, I can try that right away on some of the LEDs, because they are driven by a buffer. For those I can just drop the series resistor. Two others though that are drive right from an MCU that only has 2 mA available, that will require some circuit revision to accomplish.

I read this to mean that the limiting factor is the current available on the output of the MCU and not the power supply. It could be that the PS is also a limiting factor, but I haven't seen that in his posts. (I certainly could have missed it.  :) )
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armdnrdy

I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

davent

Ultra brite 'regular current' LED's can be run at well under 1ma, i'm regularily under half an ma and they're still plenty bright enough in a 'bare' application. Those Vishays are only 2mcd at 2ma, no idea what the currnet vs. mcd ratings would be with the regular Ultra brites but they're rated in the 1000's of mcd at their regular current.
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amptramp

There is always the option of using a photosensor to control the light output along with a series resistor to limit the maximum current and a parallel resistor to put a lower limit on the dark current.  If you are playing a dark roadhouse, the current is limited.  If you are playing a stadium, well, you have made it, haven't you?  You can afford a case of batteries and a roadie to swap them out when you ask.

The photosensor can also fit under the label.

italianguy63

Quote from: Perrow on May 25, 2015, 07:37:42 AM
Playing while kayaking?

I'm assuming Randy is the supplier for the equipment to GWAR.  That would answer that.

MC
I used to really be with it!  That is, until they changed what "it" is.  Now, I can't find it.  And, I'm scared!  --  Homer Simpson's dad

Perrow

Quote from: italianguy63 on May 26, 2015, 10:14:04 AM
Quote from: Perrow on May 25, 2015, 07:37:42 AM
Playing while kayaking?

I'm assuming Randy is the supplier for the equipment to GWAR.  That would answer that.

MC

They go kayaking often?
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italianguy63

Quote from: Perrow on May 26, 2015, 10:41:55 AM
Quote from: italianguy63 on May 26, 2015, 10:14:04 AM
Quote from: Perrow on May 25, 2015, 07:37:42 AM
Playing while kayaking?

I'm assuming Randy is the supplier for the equipment to GWAR.  That would answer that.

MC

They go kayaking often?

Now, that would be a party.

MC
I used to really be with it!  That is, until they changed what "it" is.  Now, I can't find it.  And, I'm scared!  --  Homer Simpson's dad