[SI-LIST] Re: Insertion Loss of Passive Components
- From: "Hill, John" <John.Hill@xxxxxxxxxx>
- To: <ryan.satrom@xxxxxxxxxxx>, <si-list@xxxxxxxxxxxxx>
- Date: Wed, 13 Dec 2006 09:38:19 -0500
Ryan,
Consider a filter, in the pass band the filter can have a lot of
inductors and capacitors between the source and the load, but the
insertion loss is low. This is because all of the inductances and
capacitances resonate together without changing the real value of the
impedance.
Now consider the same filter in the stop band. The inductors and
capacitances do not resonate together and either changes the real value
of the filter or makes it very non-real.=20
The point is that in the pass band the filter correctly matches the
source impedance to the load impedance and in the stop band the filter
deliberately miss-matches the impedances.=20
Look at your circuit as a filter. Is it matching or miss-matching the
source to the load? Remember digital signal are wide band signals. We
typically need to design our signal paths as low pass filters with high
cutoff frequencies.
As we all know, it is an analog world.
Best regards,
John
John Hill
Design Engineer
TK HOLDINGS INC =20
Electronics=20
27200 Haggerty Road Suite B-12 =20
Farmington Hills, MI 48331
Office Phone: 248 699 2915
Mobile Phone 248 765 3599
=20
---------------------------------------
The information in this email and attachments hereto may contain legally =
privileged, proprietary or confidential information that is intended for =
a particular recipient. If you are not the intended recipient(s), or the =
employee or agent responsible for delivery of this message to the =
intended recipient(s), you are hereby notified that any disclosure, =
copying, distribution, retention or use of the contents of this e-mail =
information is prohibited and may be unlawful. When addressed to Takata =
customers or vendors, any information contained in this e-mail is =
subject to the terms and conditions in the governing contract, if =
applicable. If you have received this communication in error, please =
immediately notify us by return e-mail, permanently delete any =
electronic copies of this communication and destroy any paper copies.
---------------------------------------
-----Original Message-----
From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx]
On Behalf Of ryansatrom
Sent: Tuesday, December 12, 2006 3:49 PM
To: si-list@xxxxxxxxxxxxx
Subject: [SI-LIST] Insertion Loss of Passive Components
SI-Listers:
I have set up a simulation and am very confused by the results. I=20
have a differential trace in series with a connector launch.
I am getting very strange insertion loss results so I'm hoping=20
somebody could help advise me as to whether my model is wrong, or I=20
am wrong.
When I view the differential insertion loss of the system (both=20
subcircuits in series), the loss is better (there is less loss) than=20
the differential insertion of the trace only. Is this possible? I=20
always thought that it was impossible to improve the insertion loss=20
by adding a passive component. And I think I still believe that, but=20
now I'm getting a little confused.
It's also important to note that the single-ended insertion loss=20
results seem to be as expected. That is, the insertion loss of the=20
system is worse than the insertion loss of either individual=20
component.
Is something occurring with the differential signal to allow it to=20
perform better?
Please advise. Thanks in advance for your response.
Ryan Satrom
Everett Charles Technologies
ryan.satrom@xxxxxxxxxxx
------------------------------------------------------------------
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 FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
List archives are viewable at: =20
//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 FAQ wiki page is located at:
http://si-list.org/wiki/wiki.pl?Si-List_FAQ
List technical documents are available at:
http://www.si-list.org
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:
