First I apologize for being completely noobish with this question.
I want to use a .5watt LED as a strobe. I found a nice schematic using a 555 timer and pot to vary the time between blips, but what I really want is two quick flashes, 2 second pause, and repeat. I was talking to a friend who is an electronics guru and he was talking about adding this and that to the circuit when it occurred to me that a Arduino could do this easily.
But, the Arduino is way too big for what I am using it for. But I do have three ATTiny85 chips in my desk that I've never used before. Could I use one to drive a MOSFET transistor? I have absolutely no idea what I would need to make it work, which is why I ask you all. I can write the code easily enough, but the electronics side is still a bit of a mystery to me.
I have 21-17 Volts coming in (it's a Lithium Poly battery powering a hexacopter). I was thinking of using a 1000uf Cap just after the power comes in/out, then branching positive in two directions- one to a 3.3V regulator to power the AT chip, and the other through a 100ohm resister (if I did my LED math right), to the LED, then to the MOSFET transistor, then back to ground. My issue is, do I need anything else? Can I run a digital output to the MOSFET by itself, or do I need a resistor? How do I determine the resistance needed? What other obvious noob thing did I forget about?
Any help would be greatly appreciated.