--- In Electronics_101@..., "lcdpublishing"
<lcdpublishing@...> wrote:
Hi Guys,
I am losing a lot of hair on this one.
I have two PCBs that both have MAX232 chips. One is a cpe the other
has an N suffix. That part really doesn't matter as I have swapped
the chips back and forth (they are in sockets) a number of times and
the problem doesn't follow.
Both PCBs have 10 uf caps. One boad has caps from Radio shack - it
works. The other board has caps from Jameco or Digikey, not sure.
Either way, they ARE marked 10uf 50V.
For both devices, the proper value for the capacitors is 1 ufd, not 10
ufd.
For the MAX232N: pin 2 should be +8.5V and pin 6 should be -8.5V if
the charge pumps are working.
For the MAX232CPE: the datasheet says +10V and -10V on the same pins.
Richard
