Originally Posted by
erv
that's 100% correct, the makoto design if full parallel, means that the used current is divided equally between each led, or almost (minor differences, if the forward voltage of each LED isn't totally contant, drift over temperature etc).
Like eandori mentionned elsewhere in another thread, it's not the best configuration, but this shouldn't be taken as a generic remark.
If the forward voltage of the LED is like 3V, like the new green one I've used, then you can reasonnably put 2 LEDs in serie, then wire the pairs in //. This will divide the used current by 2 but requires 6 volt to work at an equivalent brightness.
However, with a 7.4V battery setup, 6V are low enough so that you can get autonomy and do regulation. It means that 7.4V will be "adapted" to match 6V, but even with the batteries going down the regulator will maintain the 6V on the output until the battery gets close to, let's say 6.5V.
Knowing also that the batteries will actually start around 8.4V and will remain at 7.4V for a long time (if you choose appropriate capacity versus the used current).
Just like the current CF, if I release a ledstrip version of the board, current, or at least output voltage to the strip will be configurable, of course.
For now, like eastern has tried, you can put CF to the maximum of 1.5A to drive the ledstrip. However, with all the LED in //, that not optimum, 2A will be better, but that's above the capacity of the current regulator (luxeon driver side of the board). Like he said, even with that, the LEDs are already overdriven, I've been to 31 mA per LED when I tried with the overdriven MR strip and my HB experiment.
So far, before getting in the final design of the controller, I'll build a complete blade so that I have the exact requirements and specs for the board.
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