According to IPC-SM-782,  from around 3-4% misses to less than 1%.
Reference: Figure 5-2, pg 46.
Also, see section 5.7.1, para. 5.  Square pads would further reduce false
probing.

Roger M. Stoops, C.I.D., PCB Designer


Trimble
Engineering and Construction Division
5475 Kellenburger Rd.
Dayton, OH 45424-1099 USA
Ph: +01 937.233.8921 or +01 937.233.4574 ext 288
Fax: +01 937.233.7511






                    Lothar Thole
                    <Lothar.Thole@V        To:     [log in to unmask]
                    SL.COM.AU>             cc:
                    Sent by:               Subject:     [TN] 32mil vs 40mil
                    TechNet
                    <[log in to unmask]
                    G>


                    03/07/01 03:02
                    AM
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                    Please respond
                    to Lothar Thole





What reduction in false probing could be expected if 32mil test pads were
replaced by 40mil pads on a 900 node HP3070 fixture?

Lothar Thole
=======================================================
Lothar Thole
Manufacturing Manager
Vision Systems - ADPRO
Second Avenue, Technology Park,
MAWSON LAKES, SA 5095,
AUSTRALIA.
tel: +61-8-8300-4747 (direct)
tel: +61-8-8300-4400 (switch)
fax: +61-8-8300-4422
mobile: +61-407-166-600
email: [log in to unmask]
web site: www.vsl.com.au/adpro
=======================================================

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