In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Electronegativity wrote:

Thanks Guenther, That's a really good piont.

I totally overlooked the energy dissapated by the resistor.

I was going to incorporate 4 switches that use a 10K resistor to an input pin and have the switch draw the trickle current to ground when pressed. It seems from what you wrote that this would continuously drain power by heating the resistors.

I must admit though that I don't completely understand the second part of your post.

If you generate a 50% duty cycle then that is the same as putting 5V through the resistor for half as much time, so why isn't the power dissapated 1/2 as much (5.025 mW)? 
Where did the extra factor of 2 come from?

I could see if you used capacitors to smooth out the square wave that you might be able to generate an actual 2.5V supply, but it seems to me that this is a 5V supply that is on 50% of the time.

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