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Dear Development Team Great tool!

https://www.circuitlab.com/circuit/ptpaf7/cmp_test_fail/ Does this Analog comperator work correctly? Have a look at the Time domain. To me it should not have a built in hysteresis or do I miss something?

Background While developing an step up V converter where I normaly use an HC14 as ocilator (resistor feedback + cap to ground) I needed to simulate an HC14 and tried to use the Analog Comperator and as it did not work I narrowed down the problem to the Analog Comperator.

System Should not have to much influence here but anyway: Firefox 12 on XP 512 ram... Java US 7 10.5.1.255

Regards

Try making the time step 0.01 Then I get an expected result I think some times the solvers used have trouble with nonlinear step.

thanks

@membercare,

@Garrett is right.

About Time Steps and Stop Time.

Setting the right Time Step size is very important to get a realistic simulation and setting the right Stop Time is also important so that you run the sim for long enough for it to start up and/or reach a steady state.

See:

https://www.circuitlab.com/circuit/d4qjc5/relaxation-osc-fixed-01/

for more background.

However, in many astable and oscillator circuits, the circuit has to be given an initial kick to get it started or to speed up the startup.

Unlike mature spice simulators, CL does not yet allow a sim to be plotted from an arbitrary time after T=0 so if you need a long time for a circuit to start up or settle and a small time step to get the detail right you end up waiting ages for the sim to complete and then the little bit you may actually be interested in is lost in a huge plot so you have to wait ages again for the zoom to sort itself out.

Have a read through some of the examples in:

https://www.circuitlab.com/browse/by-tag/initial-conditions/

https://www.circuitlab.com/browse/by-tag/startup/

and:

https://www.circuitlab.com/circuit/b24363/ramped-and-glitched-signals-and-supplies-01/

See also:

https://www.circuitlab.com/docs/faq/#q_unrealistic_spikes

BTW: Firefox 12?

That's very old now. You could do with updating that.

:)