Hello all, im trying to build some kind of frequency-voltage converter, i started out with the first block which is a comparator with internal hysteresis, so it doesnt need external resistors, and vref is vcc/2.

I did the simulation after importing the component, but in output i dont see a square wave with 50% duty cycle, why so? the circuit connections should be simple,i dont explain my self why i dont see any, consider that output is push-pull.

Thanks all

 

It sure looks like that should produce a square wave output. Are you certain of the device model, because that is the only thing I see that might be wrong.

 

It sure looks like that should produce a square wave output. Are you certain of the device model, because that is the only thing I see that might be wrong.

Yeah its the correct one, i copied the parameters in the directive and created a symbol with .SUBCKT TLV7031 IN+ IN- V+ V- OUT , right clicking on this.

 

Hello all, im trying to build some kind of frequency-voltage converter, i started out with the first block which is a comparator with internal hysteresis, so it doesnt need external resistors, and vref is vcc/2.

I did the simulation after importing the component, but in output i dont see a square wave with 50% duty cycle, why so? the circuit connections should be simple,i dont explain my self why i dont see any, consider that output is push-pull.

Thanks all

Remove the .subckt statement from your schematic.

Change the .trans duration to something reasonable so you can see the 3khz waveform.

Per=1/3k=333.3 usec (one cycle) x 10 cycles= 3.33 msec

Maybe like this:

.tran 0 5m