OPAMP comparator hysterisis

[myfaithnka]

Hi all,

LM358,3v from tl431,regulated from a SLA battery of 6v.

this is an opamp comparator circuit i made to cut off the cfl emergeny lamp i made months ago.

the problem i am facing is that this circuit puts off oscillations,but again SLA battery recovers voltage to to be switched on by comparator.

so i am looking a way to make this circuit once turned off,only be turned on at a voltage of 5 v.

how can i bring hysteresis to this circuit?


please help.

 

[Ogu Reginald]

To take care of the hysteresis, add a feedback resistor between the output and the non inverting input.

 

[chuckey]

As above, but make that a high value resistor, say 1 M to start with, will add 3mV Hysteresis. Vh = 3V X 1K/new resistor
Frank