On Wed, 19 Oct 2005 06:47:59 +1000, you wrote:

>
>Greetings Piclisters.
>
>I currently have a 78L05 (100mA) in the WARP-13 but with the possible 
>change over to USB via a 18F2550 it tends to run just a little hot.
>
>My question  is if I change it over for a Zetec ZSR500C that is rated 
>for 200mA does it follow that the output drive is lower impedance and 
>therefore if I draw the same amount of current from it, it would not 
>generate as much heat as the 78L05? Right/Wrong?

No. 
Linear regs burn off the difference between input and output voltage as heat, so the device rating
makes no difference. 
Heatsinking, changing to a TO220 package, reducing input voltage or load current are the only things
you can do.
Could you run the PIC off the USB supply instead ?


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