[SI-LIST] Re: LVDS Termination
- From: "Tabatchnick, Justin" <justin.tabatchnick@xxxxxxxxx>
- To: <si-list@xxxxxxxxxxxxx>
- Date: Thu, 10 Apr 2003 21:16:53 -0700
Mike;
I don't quite understand your approach , it seems to me that you will
still get large reflection because your load impedance is now complex
with the addition of the cap and the real part is still a large
impedance. Can you elaborate more ?
Thanks
Justin
-----Original Message-----
From: Mike Brown [mailto:bmgman@xxxxxxxxxx]=20
Sent: Thursday, April 10, 2003 8:08 PM
To: kenneth.w.siders@xxxxxxxx
Cc: 'si-list@xxxxxxxxxxxxx'
Subject: [SI-LIST] Re: LVDS Termination
Think about driving the 2 lines in parallel, with only a high-Z path to=20
ground at the receiver input (the condition without the cap). Without=20
the capacitor, the CM reflection coefficient approaches 1. With the=20
cap, it approaches zero. With an appropriate resistor in series with=20
the cap at the CT of the 50 ohms, it can be made to be zero.
The obvious drawback is parts count and board real estate.
Regards
Mike
Siders, Kenneth W wrote:
>Hello Group,
>My question concerns terminating an LVDS receiver with two 50 ohm
resistors
>in series with a center tap capacitor to ground across the inputs of
the
>receiver to achieve better common mode noise rejection? What type of
>improvement if any will I see. Also, are there any draw back with this
type
>of termination.
>
>Regards,
>Ken
>
>Ken Siders
>Sr. Design Engineer
>Lockheed Martin MFC
>5600 Sand Lake Rd.
>MP 916
>Orlando, FL 32819-8907
>Phone: (407) 356-4891
>Pager: (888) 363-3411
>Fax: (407) 356-8944
>Email: kenneth.w.siders@xxxxxxxx
>L
>
>------------------------------------------------------------------
>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 archives are viewable at: =20
> //www.freelists.org/archives/si-list
>or at our remote archives:
> http://groups.yahoo.com/group/si-list/messages=20
>Old (prior to June 6, 2001) list archives are viewable at:
> http://www.qsl.net/wb6tpu
> =20
>
>
> =20
>
------------------------------------------------------------------
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 archives are viewable at: =20
//www.freelists.org/archives/si-list
or at our remote archives:
http://groups.yahoo.com/group/si-list/messages=20
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
=20
------------------------------------------------------------------
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 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:
