[SI-LIST] Re: Rise time bandwidth relation
- From: "Tom Dagostino" <tom@xxxxxxxxxxxxx>
- To: <a.ingraham@xxxxxxxx>, "'si-list'" <si-list@xxxxxxxxxxxxx>
- Date: Tue, 8 May 2007 13:59:29 -0700
Staric and Margan did a very easy to understand derivation of the
relationship between risetime and bandwidth in their book "Wideband
Amplifiers". See chapter 2.
Tom Dagostino
Teraspeed(R) Labs
13610 SW Harness Lane
Beaverton, OR 97008
503-430-1065
tom@xxxxxxxxxxxxx
www.teraspeed.com
Teraspeed Consulting Group LLC
121 North River Drive
Narragansett, RI 02882
401-284-1827
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On
Behalf Of Andrew Ingraham
Sent: Tuesday, May 08, 2007 10:21 AM
To: si-list
Subject: [SI-LIST] Re: Rise time bandwidth relation
> Can somebody help me in understanding the derivation of the
> following formula for digital signals:- Bandwidth = 0.35/Rise time.
Don't they teach that in college anymore?
I guess I shouldn't be surprised..... :-(
Someone on this list (I think it was Howie Johnson, but might have been
someone else) wrote a lengthy discussion about this formula and others like
it, on the SI-List a few years ago, maybe a couple of times. (Some form of
this question comes up every couple of years.) He derived the formulas for
the most common cases of theoretical interest, including single pole and
gaussian responses. Maybe you can find it if you search the archives.
> In the
> instance of an infinite pole, all pass filter a.k.a coax cable, I've
> read that BW ~ .31/Tr (10% to 90%). Can anyone clarify the origin of
> THAT number?
Certainly not!
Or was that meant as a trick question?
An all-pass response such as a lossless coax cable, would have infinite
bandwidth, so the formula above would be meaningless.
Or perhaps you meant lossy coax with some assumed low-pass response...?
Regards,
Andy
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List technical documents are available at:
http://www.si-list.net
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List technical documents are available at:
http://www.si-list.net
List archives are viewable at:
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
