02-13-2015 04:58 AM
Hi all of you
I'm using Multisim 12.0 to do personal research in electronic. In the present lab, I multiply the sinusoidal and square signals using AD633AN component (U8) and the circuit works fine. But when the square signal is complemented before being used in AD633AN (U1), the transient analysis fails with a 'time step too small" error.
Please, kindly help me to fix this issue.
Circuits in JPEG and Multisim format are ateched
02-14-2015 04:58 PM
Hello buddy.
I was able to reproduce the situation and have found the partial solution.
first of all a few thoughts -
for simulation you do not need to add blocking caps - they will just slow down the simulation.
in order to get 2 opposite phased waveforms I am using builtin generator called Function generator XFGxxx - it has 3 options for wave shape and 2 opposite phase outputs .
check out the attached file( it is in ms13 format, sorry I do not have version 12.)
but there is the snapshot.
problem begins when 1 or both input signals are meanders (square shape). I do not know why it is happening, I guess the reason is the way the MS simulate the meander - the rises are to short , problem with dividing on zero or something like that. I tryed to use automatic solution finder but with no results.
so after you manage to reproduce the schematic in your MS12, switch both generators to sine and start simulation.
then switch one to triangle and see the results,
then switch the second to triangle,
and then try to switch one of them to meander.
I have been doing it a few times - some times it works, some times it is stocking the simulation.
good luck.
Michael
02-24-2015 10:43 AM
Hi Michael
thank you for your contribution. I've tried your solution. It's only ok for bipolar square signal. In my case, I need unipolar square signal and the multiplier does not walk when I use the inverted square signal.