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#1 Oct 10, 2018
changqiy
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Joined: 2018-10-10 20:19

Problem with easy circuit simulation

Hi all,

I have been using Pspice for a half years, today I met a very wired problem with Pspice simulation.

I tried to simulate a very simple RC circuit. But the simulated waveform is absolutly wrong. I put 5V, 1k Ohms R and 1uF C in series, attaching V probe at C.

Theoretically voltage of capacitor should increase gradually and time constant should be 1ms. But I observed simulated waveform for capactor volatge is 5V at t=0s.

Does any one know how to fix this stupid problem.

Thanks in advance.

btw: how to attach pictures here?

Thu, 2018-10-11 07:23
RobertoGb
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Joined: 2016-05-24 03:10

Hi,

Make double click on the Capacitor and define the property IC as IC=0. It means the capacitor is not charged at the time t=0s. 

You can attached a pic using Internet Explorer. 

Regards

Thu, 2018-10-11 12:08 (Reply to #2)
changqiy
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Joined: 2018-10-10 20:19

Hi, it does help me. Thanks a lot.

Fri, 2018-10-12 07:32
Pviny
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I think it  is  a   software  problem.It  sometimes happens.It also means that the software has not the intelligence to deal with this thing.It may need to be modified.Take for example the same problem of  time circuit done through a book.If  you actually test it with meters or osciloscopes probably it will show the correct waveform.If in that case also it shows the wrong waveform then the circuit is wrong ,which in your case seems unlikely.It is good point to discuss in future.

Fri, 2018-10-12 12:47 (Reply to #4)
changqiy
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Joined: 2018-10-10 20:19

Yes, I do see some glitches happened on my maganetic switch simulation. Current flew throuth inductor is discrete but not continous. So far I have not yet found a fix for the problem. It's really annoying.

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