Subject: | |
From: | |
Reply To: | TechNet E-Mail Forum. |
Date: | Thu, 19 Nov 1998 08:05:35 -0500 |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Ken,
1) True position is to the drill tape specified position. Best way to get
a handle on this number is to look at your process capability by measuring
position on a large number of your small holes on the bottom panel of the
stack and perform the statistics.
2) Front to back is a layer to layer registration specification. Features
on different layers that are supposed to line up exactly should not be more
than 0.005" out.
Jeff Perkins
-----Original Message-----
From: Ken Patel [SMTP:[log in to unmask]]
Sent: Wednesday, November 18, 1998 8:03 PM
To: [log in to unmask]
Subject: [TN] True Position and Registration on Fab
Fab Gurus,
We are designing board with a 40 mil BGAs first time and the fab will be
having 10 mil plated finished holes on it. I opened up an old existing
drawing of different non-BGA board and now I have couple of questions after
reading my fab drawing notes.
(1) Fab note: All holes to be within .006" true position on the diameter
with respect to original data.
Question: What is true position and why .006"? How to decide this number?
(2) Registration: Front to back to be within +/-.005". Can anyone explain
what is registration and why .005"? Who can decide this #, is it fab
house's
processing capability?
re,
Ken Patel
______________________________________________________
Ken Patel Phone: (408) 490-6804
1708 McCarthy Blvd. Fax: (408) 490-6859
Milpitas, CA 95035 Beeper: (888) 769-1808
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following
text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section
for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or
847-509-9700 ext.312
################################################################
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information.
For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312
################################################################
|
|
|