Re: TI-H: SPinTerface build question

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Re: TI-H: SPinTerface build question

Tony Do wrote:

> I noticed that.  This thing is HUGE!  35V input voltage?  1A output
> current?  I don't think this is needed.  I'm not big in electronics
> (yet) but this sure doesn't seem like the smallest thing we can use.

Yeah, I'm using one on my bench supply to supply a whole crudload of
stuff. Its definitely overkill.

> That sounds right.  But then how come Rich can somehow expect us all to
> get 5 volts in the troubleshooting section of his page?  Did he verify
> it on his calc?

He probably never tested it himself, or possibly did get 5V out... with
a 6V input, it is possible... but the regulator output would not be
stabilized and any fluctuations in current draw (I.E. a gate switching
in the Expander memory chip, etc) would make the regulator output
go haywire.

> So can I just swap regulators and that will solve the problem?  Or is
> there additional wiring involved?

Yes, but the new low dropout regulator may have a different pin out.
Its fairly hard to blow out a regulator, and at $0.35 each it doesn't
matter if you do anyway. So you might as well try. The ground pin
is usually the middle one.

-----

On a side note, as I was experimenting with my Extender uP prototype
I accidentally shorted one of TI connector pins to unregulated 14 VDC
going into my bench supply. Unfortunately, this totally screwed my
PC's I/O parallel port I/O controller (I'm happy my entire PC
isn't screwed... those put everything in one chip chipsets are the
dumbest load of bullsh!t I've ever seen) so my parallel port no
longer works... since everything I own is parallel, I'm essentially
out of business until I can buy an ISA I/O card. Strangely, the port
still works fine for my printer... but the quickcam and my TI link
are broken (I probably blew out the driver gate for one of the lines.)

I have a graph link, but I need a parallel port to burn PICs. Just
letting the list know... if anyone cares... :-) the Extender uP
is pretty much stalled now. :`((((

Bryan Rittmeyer
bryanr@flash.net
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