Hello everyone.
just finishing my list to go to the candy shop to get some parts.
I have some 78L05 regulators and I would like to ask if its possible to use instead of the 7805?
Ive read in some pages that there would be a problem with the pins, but the 78L05 would fit in the layout. But to follow the specs, I would need to interchange pins 1 and 3.
From the layout it seems that would fit a TO92. Might be missing an "L" on the schematics?
The suggestion is the capacitors before and after that might need a change..
anyone ever tried this?
thanks a lot
I haven't built a Sea Urchin, but the main difference between the 7805 and the 78L05 is the current handling. The ZeroPoints are OK with the 100mA output of the 78L05, so I'd guess the Sea Urchin would be too. As far as the caps go, the regulator would probably be happier with some small bypass caps in addition, but I think it'll be fine with what is there too.
hey RobA
as far as I understood I should change the pins 1 and 3 too right? the input of the 7805 is on the pin 1 and the 78L05 is on the 3 :-\ :o
I think you can actually measure that? Socket the regulator, and put it in there, then take out the ol' DMM and measure. If it's not 5V you get, spin it 180 degrees. Just make sure the PT2399 is not on the board when you try this (again, socket) as they die when faced with anything higher then 5V.
Paul
If you can find the spec sheet for the part you've got from the manufacturer, check it out there. I've seen different orientations for specific regulators. The parts sheets I've got do show the 7805 and the 78L05 from Fairchild exactly flipped 180°.
I think you could get away with checking the voltage output as long as you did it fast. I've actually blown up a couple of LM7915's by putting them in backwards and letting them sit too long. And by blown up, I mean shrapnel flying all over the place -- pretty impressive bang too.
i dont remember which one is the L one but ive built 2 urchins and ive used the bigger one with no problems and no twisting of leads :)
I will put it in a breadboard and measure the voltage without the iC and see!
I hope nothing will explode it
Thanks for helping