hello. i am planning to power an arduino in my car, with a 5V voltage regulator. (i will be using a protective circuit before the Vreg , to protect from cars spikes)
my question is this. the heat generated by the vreg is (Vin-Vout)*I ? (in watts).
the problem is that the voltage regulator will work ALWAYS. it will never stop...
BUT the arduino want draw much power.. it will work something like this: for 3 days, it will be drawing about 10mA. some times on that 3 days, it will draw about 60mA. and some other times , about 30mA.
so the heat generation, want ever be big. but, since it will always be there, will a big heatsink, solve the heat problem?? or after some time, it will become overly heat? do i need to use a small fan to cool it down??
P.S1 (i can use a very big heat sink, and i can use a 2A Vreg, to generate less heat in small currents?)
P.S2 . what about the decoupling capacitors?? can someone shed a bit light on how to hook them, and what they are for?? thanks allot!!