MAX3243E: Recommended DPST switches.

Valid RS-232 signal levels are up to ±15 V. Switches like the TMUX6119 can handle this, if you have appropriate supply rails.

The actual output voltage of many RS-232 transmitters is lower. What ICs are you using? How many channels do you need to switch? What power supply voltages do you have available?

Hi Kengo,

If you are switching all the bus switches on the MAX3243E you need 8 channels for the multiplexer for the MAX3232E you need 4 channels.  RS-232 can have up to +/-15V on a line which will require a mid-voltage multiplexer with +/-15V source - the TMUX6119 is a potential option but you'd require multiple IC's. The MAX3243E typically is only putting out +/-5.4V - but I think because of the range the TMUX6xxx or TMUX7xxx families are still the best bet in finding a switch that will work. However I am going to tag the Multiplexer team in the reply to see if they have another option that they may want to highlight. In  general a lot of switches don't integrate too well with RS-xxx standards due to the large possible  voltage ranges - there are work-arounds  but they aren't always the most practical as they usually require voltage supplies beyond what is needed for the transceivers themselves. 

Best,

Parker Dodson

Hi Kengo,

For a 2:1 switch with +/-15V capability, you can looking into our TMUX62XX family which support voltages up to +/-18V. Some suggestions would be the TMUX6219 (2:1x1 channel), TMUX6236 (2:1x2 channel), or the TMUX6234 (2:1x4 channel).

If you have other requirements, please let me know and I can help suggest other devices as well.

Thanks!

Bryan

Hi Bryan,Parker, Clemens

Thank you so much for your help !!
I understood.

I'll recommend TMUX62XX family  to my customer.

Sincerely.
Kengo.