[mrcheese321]

Hey everyone,

I'm trying to build a battery pack for my Vaio Pocket. It runs off of 5.2 volts.

I have 4 AA batteries in series and then a 7805 5v regulator to make it 5v.

I wired up everything as the instructions say, but the multimeter is reading 6v still.

anyone have any suggestions?

c

 

[mono]

Alkaline or rechargeable battery?

It's probably fine at 6V, since use will soon enough drop the voltage significantly. If you just need a minor voltage drop then consider putting a diode in series on the power lead, because the dropout (voltage loss) from a 7805 regulator can easily be higher than 0.8V, it is not really suitable for this use. If you really want to use a regulator, consider an "LDO" type or a simplier pass-transistor setup (Google should find simple schematics).

However, I'm wondering if you wired it right? No matter what there should not be same voltage on the output of the 7805.

If you have a good detailed picture of the circuit that might help figure out what's up with the 7805 but otherwise I just wouldn't use it.

 

[BlazerFRS]

I'd prolly just throw a $0.50 diode inline with the thing and call it a day; they usually have voltage drops of between .6 and .8 volts, which should get you close enough.