hello friends,I have got a problem with making a Regulated power supply, that how to choose a heat sink for preventing the damage that might be occured. i have used LM317 IC for regulation.
And, I want to use a short circuit protector circuit, which intimate us by glowing an LED whenever we short the load terminals.For this, i can use 555 IC, as it is working as a toggle flip-flop.But, I need a seperate Vcc for that. Is there any other method to do kile that....
thank you.....,
CHANDU

 

I have designed a 555 as a toggle flip flop, it may even be what you are referring to. We need a schematic of what you have to date to be able to help you though.

 

Hello,

The size of the needed heatsink depends on the power to be dissipated.
At a LM317 it will be about (Vin-Vout)*Iout.

Here is a page about heatsinks:
http://sound.westhost.com/heatsinks.htm

And here a page how to make a heatsink yourself:
http://sound.westhost.com/articles/diy-heatsink.htm

Bertus