MAX3232E-Q1: schematic review

Hi Liping,

I don't see any major concerns. (It should be functional)

Some notes:

• The 100 ohm series resistors will affect the max speed and the distance you can communicate. The larger the resistance the more it will affect the communication. If you have to use serries resistors I would probably say 33 ohms would be better.
• Your ESD clamping voltage looks like it's out of the abs max for our device (especially on the DOUT pins). 
  • You should try to clamp DOUT before +/-13V and RIN before +/-25V

I've reassigned this thread to the ESD team to see if they can recommend a bi-directional TVS diode. If you have a required ESD rating, you can let them know.

-Bobby

Hi Liping,

For the DOUT lines, TPD1E10B06-Q1 is our best automotive qualified option. It has a working voltage of 5.5V and can clamp before 13V.

For the RIN lines I would recommend ESD501-Q1. It operates at -12V to 12V to support RS-232 protocol and can clamp the lines below 25V.

Best,

Chris