Lpc2000

----- Original Message ----- 
From: "David Willmore" <willmore@...>
To: <lpc2100@yahoogroups.com>
Sent: Wednesday, January 07, 2004 10:11 PM
Subject: Re: [lpc2100] MAX3232 problems?


> Hello, Leon.
>
> > It sounds as if the MAX3232 has failed, it shouldn't take anything like
that
> > amount of current and shouldn't be warm. Many years ago I had quite
frequent
> > failures of the earlier version of this type of chip, caused by
connecting
> > the host machine to my board whilst the host was powered up. The current
> > chips have ESD protection and seem a lot more robust.
>
> Are you talking about the difference between the MAX3232 and MAX3232E kind
of
> difference?

No, I'm talking about the original MAX232, 20 years ago. 8-)

>
> > Check the voltages on the charge pump capacitors, if they are wrong
(IIRC
> > they should be about +/- 5V and +/- 12V) it won't work. Make sure you
> > haven't got any shorts. Have you tried a new chip?
>
> They are off. They're more like 2.7V and 5.5V and -5.1V.

2.7 V is definitely wrong.

Leon
--
Leon Heller, G1HSM
Email: aqzf13@...
My low-cost Philips LPC210x ARM development system:
http://www.geocities.com/leon_heller/lpc2104.html