My Flip-flop multivibrator LT spice simulation is not working

[neptune]

what is wrong with this circuit.
transient analysis = stop time 100ms , start time 0ms , maximum timestep 10

 

[ericgibbs]

what is wrong with this circuit.
transient analysis = stop time 100ms , start time 0ms , maximum timestep 10

Look at these images... you have tran settings wrong.

 

[neptune]

how did it worked ? i used the same transient settings.
i am getting this

 

[ericgibbs]

how did it worked ? i used the same transient settings.
i am getting this

hi,
Like i said the .tran is wrong

You have a STOP time of 0.1second and a Time STEP of 10 seconds.

Note: the Time Step is the intervals which LTS calculates the plot points.!

so your total Stop time for the plot is 0.1 second and the next interval is 10 seconds later.

The STOP is the length of the Time Axis of the plot.

Do you follow OK.?

 

[neptune]

what transient settings should i use then, my 1/RC time constant is 1/100s alternatively frequency is 100Hz
image attached

 

[ericgibbs]

what transient settings should i use then, my 1/RC time constant is 1/100s alternatively frequency is 100Hz
image attached

hi neptune,
Post your asc file and I will modify it for you.

 

[ericgibbs]

what transient settings should i use then, my 1/RC time constant is 1/100s alternatively frequency is 100Hz
image attached

Look at this marked up image.

 

[alec_t]

Use Simulate/Edit simulation Cmd, empty all the boxes in the pop-up dialogue, then just enter 0.3 in the Stop Time box.

 

[neptune]

i got this using same settings.
now what ?

 

[ericgibbs]

i got this using same settings.
now what ?

Look at the frequency of your bistable in post #2.
Your time axis of 500usec will not show a single waveform...

Make it 1second

 

[neptune]

ok now its coming .
but its therotical frequency is something else if you calculate 1/RC But it is showing freq. as 7Hz . ?

 

[ericgibbs]

ok now its coming .
but its therotical frequency is something else if you calculate 1/RC But it is showing freq. as 7Hz . ?

Thats better.

What do you calculate the frequency should be.??
Most electrolytic caps can have a tolerance of +/-10% or more!

 

[neptune]

if i calculate it , R= 10K ohm and C= .000001 Farad
1/RC = 0.1s , so Freq. = 10 Hz
thats 3 Hz behind :?

 

[ericgibbs]

if i calculate it , R= 10K ohm and C= .000001 Farad
1/RC = 0.1s , so Freq. = 10 Hz
thats 3 Hz behind :?

hi,
Look at this link.
**broken link removed**

 

[neptune]

ok , i forgot the formula thankyou

 

[ericgibbs]

ok , i forgot the formula thankyou

So now what do you calculate the freq should be?

 

[neptune]

7.29 Hz calculated
7 Hz shown in simulation

 

[ericgibbs]

7.29 Hz calculated
7 Hz shown in simulation

Thats close enough when component tolerances are considered.