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00:09, 24. Nov. 2014 == Idea ==
Build a cheap and simple full software controlled step-up (boost) converter to drive a LED string of 10 LEDs. LEDs are used as string to light up a acrylic engraved plate placed in a holder (also made out 5 layers of lasered black acrylic glas). Step up is from 5V to about 30V, current regulated to about 20mA.
== Circuit ==
Poti is for software features only. Current is measured by voltage at 10 Ohm resitor feedback to uC ADC3. Standard components like 1N4148 and BC817-40 are good enough for delivering 20mA output current (software limit here, more might be possible). Coil is a standard 100uH coil, but should be able to withstand 250mA as coil current is at least LED-current times boost-factor. Boost-factor is about 6 (30V LED vs 5V input).
== Download ==
All source files, schematic, Arduino code, LTSpice simulation files etc. included here: