Why LM311 comparator switches when V1+1volt>V2?

[SphinX]

LM311 Comparator ?

Salam,

I design Battery backup circuit.
I use LM311 as comparator but i have noticed the following

The comparator switch from Low o/p to High o/p when for V1+1volt>V2 !

Why 1volt ?

I want my comparator to switch as V1 as greater than V2 with equal or less than 0.05 volt

How can i do that ?

Thanks

 

[nicleo]

LM311 Comparator ?

Interesting ...

Is the LM311 driven by dual power supplies or single power supply?

What's the value (minimum) of V2? Is V2 stable enough? Pls do aware that the input of LM311 is NOT R-R.

'1V' does look like 'noise'. Anyway, you may try to confirm whether it's due to noise or not. If it's, you probably need to add 'hysteresis' loop (positive feedback) to the comparator.