Design issue Serial Comm. Isolator with Level shifting

Discussion in 'General Electronics Chat' started by geobabu, Apr 18, 2009.

  1. geobabu

    Thread Starter New Member

    Aug 13, 2008
    3
    0
    Hi,
    I am trying to implement a isolation in between a serial communication system. One side its have a RS232-TTL(MAX232 circuit) level terminal & other side contains a 3.3V based microcontroller whose power is directly driven from a transformer less capacitor based power supply. I tried a setup a circuit that mentioned in the attached file ,but it doesn't helped helped me. Please help me to rectify the error in this circuit.
    Thanks&Regards,
    Geo
     
  2. leftyretro

    Active Member

    Nov 25, 2008
    394
    2
    Well if built like drawn then your missing +5vdc power for the Max232 chip, it goes to pin 16.

    http://www.datasheetcatalog.org/datasheet/texasinstruments/max232.pdf

    Lefty
     
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