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Trying to regulate 5v from 7.4v

I have a LM2930S-5.0:

http://www.national.com/ds/LM/LM2930.pdf#

in this mess:

I have a cap across the input and a resistor in line on the output (it was 6.8 before I added the resistor).

Yes, it is a cheap meter, but measuring VCC on a Mega I get 5v and on a Fio 3.3v. It is reasonably accurate.

What am I doing wrong? I don't want to smoke my 5v uC. The VR should be putting out 5v (datasheet says 5.5v max).

 

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Note to self - read the datasheets you link to and maybe you won't look like an idiot...

Well, I took the resistor off and put a 22 uF (you may have noticed I am big on overkill) cap between the output and GND and now it reads 4.98. Thanking you is getting to be a regular thing. It's like you follow the software guy around and keep him from letting the smoke out of the chips... Thanks!!!

No cap on the output? From the datasheet: "COUT must be at least 10 μF to maintain stability".