Look thru this pdf.
E

 

I've gone through every pdf on the net, nothing is clear. They are all written from an engineers perspective. If you could share the math behind the schematic then that would give me something to start with.

 

hi anish.
This simple LTS shows the resistor chain around the comparator.
Note the change in Vref for the On and Off states of the Comp output.
Use Ohms law the derive the basic equations

E

 

To get an inverted output, should i add another opamp following the previous with the output from the first to inverting pin of the second ? or is there a better way to do it with one opamp ?

 

To get an inverted output, should i add another opamp following the previous with the output from the first to inverting pin of the second ? or is there a better way to do it with one opamp ?
View attachment 195446

You could use a simple NPN transistor not gate. That would have the added advantage of its being able to supply much more current.

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You could use a simple NPN transistor not gate. That would have the added advantage of its being able to supply much more current.

View attachment 195451​

adding the transistor would override hysteresis window.

 

But adding a series resistor to the transistor does the job.

 

View attachment 195451​

that thing is slow . . .
. . . let's see if the Falstad can make a difference . . .​

 

that thing is slow . . .
. . . let's see if the Falstad can make a difference . . .​

He could use an nFet too...

 

He could use an nFet too...

i haven't used junction-fet for DC amplification . . . other than four quadrant multiplier . . . ← but this assumed analog or smooth varying signal . . .
? Do you have some digital switching example circuit -- it would be interesting to see

 

To get an inverted output, should i add another opamp following the previous with the output from the first to inverting pin of the second ? or is there a better way to do it with one opamp ?
View attachment 195446

Hi

Reverse the input connections (+/-) on U2.

eT