I am trying to make a simulation by using Multisum 14 for i bi-directional channel for Logic level circuit from SparkFun which use Philips AN97055 IC as a Bi-directional level shifter...
My circuit design
The UN-clear part in this simulation is I'm using the low side or TX_LV to transmit serial data signal from 3.3v MCU to 5v MCU over this LLC, if I send "Logic 1" 3.3v from MCU over serial pin to the mosfet the last will read it as open circuit and don't send 5v in the other site and when I stop sending data "Logic 0" 0v the mosfet will read low pin as open circuit then drive 3.3v from pull up resister to source pin in mosfet and this make the mosfet drain pin connect to ground which the last cause drive 5v from pull up resister to TX_LV pin?
Hope to find some explain about that.
Thanks for everyone shearing his knowledge in this site,