 
| Subject: | |
| From: | |
| Reply To: | (Designers Council Forum) |
| Date: | Thu, 5 Feb 2004 12:13:53 -0600 |
| Content-Type: | text/plain |
| Parts/Attachments: |
|
|
Sorry I don't have any scientific data to back this up,
but when I used to do a lot of diff pairs the rule was
to keep other copper a distance of 3x the trace width.
The strength of the field decreases by the square of
the distance, so even adding a tiny bit of clearance can
reduce crosstalk (or whatever) a LOT.
good luck,
Jack
|---------+---------------------------->
| | Ray Dwyer |
| | <Ray.Dwyer@DALSEM|
| | I.COM> |
| | Sent by: |
| | DesignerCouncil |
| | <DesignerCouncil@|
| | ipc.org> |
| | |
| | |
| | 02/05/2004 11:57 |
| | AM |
| | Please respond to|
| | "(Designers |
| | Council Forum)"; |
| | Please respond to|
| | Ray Dwyer |
| | |
|---------+---------------------------->
>------------------------------------------------------------------------------------------------------------------------------|
| |
| |
| |
| |
|To: [log in to unmask] |
|cc: |
| |
| |
| |
| Subject: [DC] copper pour stand-off |
>------------------------------------------------------------------------------------------------------------------------------|
Caterpillar: Confidential Green Retain Until: 03/06/2004
Retention Category: G90 -
General
Matters/Administration
Greetings,
I am concerned about rules for stand-off distance for copper pour on an
outer layer to provide added isolation to a pair of sensitive low current
traces. There are other traces on the top layer as well. The basic info
is
50 ohm impedance, 10 mil wide microstrip, digital TTL signal current as low
as in 10s of mili-amps, FR-4 material, 1 oz copper.
Ray Dwyer
972-371-4046
Maxim
4401 Beltwood Parkway
Dallas, Tx. 75244
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV
1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To set a vacation stop for delivery of DesignerCouncil send: SET
DesignerCouncil NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail Archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
---------------------------------------------------------------------------------
|
|
|
