power stage frequency response, PIExpert Topswitch-GX design,

Posted by: rt60man on 11/04/2013

Hi,

I noticed that PIexpert does not redraw the Power stage frequency response even after altering the output capacitor

For eg., If PIexpert selects output capactiance of 3 x 270 uF and then I change it to 2 x 1000uF, I expect the response to roll off at an earlier frequency. That does not seem to happen.

Am I overlooking something here?

Please explain

Thanks!

Comments

Hi.

You found a bug, thanks, and sorry.

There is a work around to the bug though. once you change the output cap, go to the menu Feedback\Components. Click on the calculator symbol next to "crossover target", so that manual input is enabled, and then click again so that it is again automatic (calculator symbol). If you follow the procedure the bode plot will be updated to reflect the new output cap.

We will fix this in a future version. Once again thanks for pointing this out!

Thanks Wesley,

It would also be nice to include custom capactors (esp. for the output stage) wherein one can enter the ripple current/esr/etc of a capacitor that one source easily at time of prototyping

rgds

I have good news for you: you can add your own components including the capacitors to the software.

1 - Open PIExpert, but don't start or open a design

2 - Go to Tools\Component Library

3 - Go to the capacitor tab and select the option "Add"

4 - Enter the parameters of your capacitor

Here you can find a link to see several video tutorials, one of which will help you manage your custom component database.