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Design >> Analog Design >> strange transient reponse of low pass filter
https://designers-guide.org/forum/YaBB.pl?num=1254984914

Message started by yixiusky on Oct 7^th, 2009, 11:55pm

Title: strange transient reponse of low pass filter
Post by yixiusky on Oct 7^th, 2009, 11:55pm

Hello ^^

I attach the ac response and transient simulation result of my low pass filter. The circuit is exactly differential and symmatric. But the transient show different voltage swing. Could you help me to explain this problem? thank you very much

(1) ac response of LPF

(2) zoom in to cutoff frequency part

3) 3dB bandwidth

(4) transient simulation

5) zoom in to transient simulation

thank you very much

Title: Re: strange transient reponse of low pass filter
Post by ywguo on Oct 9^th, 2009, 2:07am

The pictures are small and vague.

Quote:

But the transient show different voltage swing.

What's your problem? What are the voltage waveforms for?