Connect with us

what to do with unused pins on MAX232/MAX233

Discussion in 'Electronic Basics' started by Michael Noone, Jul 4, 2005.

Scroll to continue with content
  1. Hi - I'm just wondering - I'm working on a board that uses a MAX233 (it's a
    MAX232 with internal caps). It has two RS-232 inputs and two RS-232
    outputs. I'm only using one of each. What should I do with the ones that
    I'm not using? In the back of my head something is telling me I should
    ground the inputs (so RS-232 input input, and the RS-232 output input, if
    you follow my wording). Is that right? Thanks!

    -Michael J. Noone
  2. Rich Webb

    Rich Webb Guest

    It's always a good rule of thumb to tie unused inputs. However, the
    MAX233 has built in pull-ups and -downs (400K up for TTL inputs and 5K
    to ground on the RS-232 side) so in this case you're covered.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day