Reply-To: "Kevin Aylward"
From: "Kevin Aylward"
Subject: Re: LT SwitcherCAD Transient Analysis
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Date: Fri, 13 Sep 2002 07:38:57 +0100
NNTP-Posting-Date: Fri, 13 Sep 2002 07:38:58 BST
"David Huhn" wrote in message
> Does anyone know if LT SwitcherCAD experiences a drastic slowdown on
> transient analysis as the circuit complexity increases. I simulated a
> few simple circuit just to become familiar with the interface and they
> came up in no time at all, however, with my h-bridge circuit, I am
> getting about 1 ns of sim time/second.
> I have played around with varying resolutions and simulation times,
> however, that has not made any significant difference. Is this a
> problem that other people have experienced?
This is most likely due to an unreal circuit description. That is,
something in the circuit is too ideal, either in a model or how the
circuit is connected. Unfortunately, SwitcherCAD is so good at
converging it can mask the fact that you should be really be modifying
something in your circuit.
*Always* make sure that no node can change infinitely fast, i.e. make
sure that there is some resistance and capacitance. This might be in the
model if a good model is used, however, ideal models may be set such
that are too ideal.
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.