[arm-allstar] power up

[Andrew Sylthe]

That's good information. I'll have to rework my circuit if if isn't
correct. I've never had an issue and it puts out a stable 5V, but I can't
argue with the manufacturer specs.

Thanks!
On Dec 5, 2014 10:33 PM, "David McGough" <kb4fxc at inttek.net> wrote:

>
> Most data sheets recommend a value of 1uF to 10uF on the INPUT side of the
> LM78xx regulators. This needs to be a good quality capacitor (low ESR),
> just as Bob mentioned. I typically use a 10uF, 50V tantalum cap on the
> input--I've got a big bag of them!
>
> 73, David KB4FXC
>
>
> On Fri, 5 Dec 2014, Andrew Sylthe wrote:
>
> > I typically use a 22 picofarad on the input, and a 10 microfarad on the
> > output of the 7805. Is that not the correct way to do things?
> >
> > Thanks!
> > On Dec 5, 2014 8:29 PM, "Bob" <Bob at fot.com.au> wrote:
> >
> > > Hi All
> > > When using a 7805 Regulator male sure you put  low ESR capacitors
> > > (10microfarad) right on the input and output terminals to ensure it
> doesn't
> > > oscillate
> > >
> > > Bob
> > >
> > >
> > >
> > > On 6 December 2014 10:12:45 "Mark Herson, N2MH" <n2mh at n2mh.net> wrote:
> > >
> > >  I'm running a pair of BBB's each from its own 7805 voltage regulator
> with
> > >> no problems. One BBB is an Element14 card (which is the Chinese
> version,
> > >> problably what comes from MicroCenter) and the other is the USA
> version
> > >> from Beaglebone.org. No startup problems have been noted at all.
> > >>
> > >> Of course, when using a 7805 voltage regulator, one must use a good
> > >> heatsink. I measured the current draw at 350 mA or so. With an 8 volt
> > >> voltage drop, that comes out to about 2.5 to 3 watts that the voltage
> > >> regulator must dissapate. This requires a pretty good heatsink.
> > >>
> > >> 73, Mark, N2MH
> > >>
> > >> > To: arm-allstar at hamvoip.org
> > >> > From: ke2n at cs.com
> > >> > Date: Thu, 4 Dec 2014 06:57:55 -0500
> > >> > Subject: [arm-allstar] power up
> > >> >
> > >> >
> > >> > Any one else have a BBB Rev C power up problem?
> > >> >
> > >> >
> > >> >
> > >> >
> > >> > http://elinux.org/Beagleboard:BeagleBoneBlack#Improper_
> > >> Power_Down....All_
> > >> > Rev
> > >> > isions
> > >> >
> > >> >
> > >> >
> > >> > I got two units from Micro Center and they both have a really hard
> time
> > >> > getting started.
> > >> >
> > >> > One unit I got from Spark Fun works fine every time.
> > >> >
> > >> >
> > >> >
> > >> >
> > >> > Ken
> > >>
> > >>
> > >> _______________________________________________
> > >>
> > >> arm-allstar mailing list
> > >> arm-allstar at hamvoip.org
> > >> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
> > >>
> > >> Visit the BBB web page - http://www.crompton.com/hamradio/
> > >> BeagleBoneBlackAllstar/
> > >>
> > >
> > >
> > >
> > > _______________________________________________
> > >
> > > arm-allstar mailing list
> > > arm-allstar at hamvoip.org
> > > http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
> > >
> > > Visit the BBB web page - http://www.crompton.com/hamradio/
> > > BeagleBoneBlackAllstar/
> > >
> >
>
> _______________________________________________
>
> arm-allstar mailing list
> arm-allstar at hamvoip.org
> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
> Visit the BBB web page -
> http://www.crompton.com/hamradio/BeagleBoneBlackAllstar/
>
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