TINA/Spice/LMC6762: Voltage input violation

Tool/software: TINA-TI or Spice Models

Hi all,

I am using LMC6762 to check the correct positive voltage level of a power rail. I am using a reference on the negative input and a voltage divider on the positive input

and the supply of the comparator is +5V and GND. However, there might be a case when negative supply voltage appears on the supply rail, so the positive input

goes below ground. According to the datasheet it is a problem (max values: +Vs+0.3V and -Vs-0.3V), but I am not sure if it damages the device or not. I check this schematics in tina spice and for the negative voltage range it gave me about -800mV at maximum on the positive input no matter how big was the negative supply (up to -20V).

So my questions are; what is the internal structure of the device that allows or not this operation? does it bear the negative on the positive input if the negative supply is gnd or does it damage the comparator and I need a low drop schottky to keep the positive input maximum below -0.3V ?

Thanks for the reply,

Andrew