Diode D20 purpose?

[Panometric]

D20 separates Field GND from PGND.

1. Why?
2. Is it recommended for the CLT-01 or the VNI8200XP or both?
3. What is the probable drawback of connecting the 2 nets without this diode protection? 

[oteri.massimo · Accepted solution]

​Hello

the diode is used only for reverse polarity protection. it is not necessary for a correct  ICs functionality

Best regards

Massimo