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Re: [N8VEM-S100:4453] MAX-232 chips

Can we please keep this thread on the original topic and not hijack it for another topic.  Please create another thread.

On Wednesday, July 2, 2014 12:03:28 AM UTC-5, Rob Doyle wrote:
On 7/1/2014 7:42 PM, norwestrzh via N8VEM-S100 wrote:
> <https://groups.google.com/d/optout>I just learned that apparently (I
> have not looked at the data sheet myself) MAXIM has changed the function
> of pin 2 on their serial line driver chip.  The old configuration was a
> polarized cap. tied to gnd. (that's the way I always wired them), and
> their data sheet now shows the cap. tied to vcc (I'm told).  Could
> account for the heat, and short service life!!! *grin*  Bottom line is
> check the data sheets, or stick with T.I. 232 chips (they still work the
> same old way).  Wonder why they did this????
> Roger

The CAP has a lower voltage across it when wired to VCC.   Otherwise it
doesn't matter.   It's just part of the charge pump.

There are also newer variants of the MAX232 that don't require polarized
caps which I prefer.