circuit design & simulating software

hello
i want a software for the simulation of the circuits, which is best

matlab is better.

Switchercad III, free from www.linear.com , 100% free (no limitations or evaluation versions), parts libraryis constantly updated, etc.

I just d/l switchercad..
very cool, but need a lil help
i am looking for the transient response .. how do i do that?

willB, use a different power source. in the parts screen select the power source labeled "voltage", which is a straight DC supply. The simulation has options to power up the DC Supply and show it in the sim profile...

some other tips: goto File --> "Demo SMPS Circuits", they are demonstrations of what SwitcherCad can do basically, good place to play around, right and left click stuff to see what it does, etc.

also, to change the value of a part you RIGHT Click ON THE PART! Right Clicking on the Label next to the part will just let you change the value of that label... does nothing for the actual part itself.

no go !
i keep getting the same error

odd, what are your settings in the simulation window?

i have no idea where the simulation window is..