I am a bit lost now - I am VERY stupid, or its just not that easy. Its coming so hard to me understanding electrics. Also, some confusing texts like "driven at 700mA" are making this more complicated for me. As far as I understand, you dont feed amps into led, you feed volts and led gives back amps. Why not say "driven at 20v" it gives xxxLm?
How long did it take you to learn and fully understand volts and amps things?
It is voltage that induces or "drives" current. Slang has given leeway to use of phrases such as 'driven at 700mA' being acceptable. You can make a fairly direct analogy between driving
LEDs with slightly differring resistances to
pipes with differring diameters. If we applied the same pressure to both, the larger diameter pipe would have a greater
flow (equivalent to current). If I ask someone to make the "
flow" (analog:
current) to be a specified number/rate, then we would need to vary/lower the pressure in the larger diameter pipe until the flows (analog: current) were equal.
So a
current source is basically
:
"a source of variable voltage such that it puts out whatever voltage is needed to 'make' the current the specified value"