is 4.7 v at the +5v ok ?

fragged8 · Post by **fragged8** » Tue Jul 24, 2007 7:57 pm

hiya
i've checked the voltage as per the instructions, im using a lab supply at +12v and checked it with the multimeter but the outputs only read 4.7v is this acceptable ?

thx

fragged

MartinM · Post by **MartinM** » Tue Jul 24, 2007 8:17 pm

It's a bit on the low side - the spec for a LM2937ET-5.0 shows within +/- 0.15v either side of 5v at 25C....and within +/- 0.25v either side across the whole temperature range.

So you're about 3% below the expected minimum at 25C

Is it getting hot? ... it shouldn't be!

Have you got the 33uF capacitors in place either side?

I've just measured one of mine at 5.15 volts.

The bottom line is I doubt it will make much difference....

fragged8 · Post by **fragged8** » Tue Jul 24, 2007 10:59 pm

hiya
i didnt run it long but it didnt smell or anything so i just carried on soldering the parts on anyway.

fingers crossed

Oliver Sedlacek · Post by **Oliver Sedlacek** » Fri Aug 10, 2007 7:34 am

How accurate is your multimeter? Everything should run at 4.7V, so it's probably fine.