How does one protect MAX3250 ISOCOM pin against ESD and surge pulse going above absolute maximum ratings?
The specified limit for the MAX3250 is 50V with an absolute maximum rating of 80V. Internal back-to-back SCRs between logic and line circuits will break down when the limits are exceeded. Therefore, an external TVS protection diode will be needed. Please contact the manufacture of the TVS diodes for a suitable part for your application.