Dummy pad 用于PCB 制造过程中，
用于内层： 是为了防止PCB板压合后出现部分压合厚度不均匀导致PCB 变形或层于层
粘合力不足。
用于外层： 是考虑到线路上电镀铜厚度，如果空旷区域很大，导致周围线路导线增
粗，增厚， 此时应在空旷区域添加一些dummy pard 来平衡周围的铜离子，
JiaXing LIU <[log in to unmask]>
Sent by: TGAsia <[log in to unmask]>
05/15/2007 05:32 PM
Please respond to
Asia Committe Task Group Forum <[log in to unmask]>; Please respond to
JiaXing LIU <[log in to unmask]>
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Subject
Re: [TGA] 答复: Re: [TGA] acti ve pad and dummy pad
Sometimes also leave some pads on non-circuit area of external lay of PCB
for plating current uniformity, so that can reduce PTH copper thickness
difference in different holes.
no special chinese name for dummy pad in this case. same meaning as false
pad.
Best reagrds
Jason Liu
Asia Pacific Strategic Sourcing
SDE
TRW Systems Consulting Services(Shanghai) Co., Ltd.
5F, 62 Building, 421 Hongcao Road,
Shanghai 200233, P.R.China
Tel:+86 21 6120 1166 or 6120 2266
Dir Tel:+86 21 6121 1811
Fax:+86 21 6120 7058
Mobile:+86 138 1895 6432
Email:[log in to unmask]
>>> Bob Neves <[log in to unmask]> 2007-5-15 17:04:42 >>>
Hello All,
In the plated through hole of a multi-layer PCB the terms that are
typically used for pads are “functional” (pads that actually carry a
signal to the PTH) and “non-functional” (pads that DO NOT carry a signal
to the PTH). This may be what is meant by “active” and “dummy”.
The designer has 2 choices for pads when designing a PCB.
First is to include pads on each layer connecting to the PTH. This would
include both functional and non-functional. This has the benefit of
reducing the amount of resin in the z-axis and therby reduces overall
z-axis expansion of the PTH when exposed to heat. The negative side to
this approach is that it leaves many more opportunities for “shorts”
between the non-functional pads and the surrounding circuitry.
The second choice is to remove these non-functional (non signal carrying)
pads from the design. This significantly decreases the possible failure
due to shorts, but increases the resin content of the PTH area and
increases the Z-Axis expansion during heat exposure.
Best Regards,
Bob Neves
Chairman/CTO
Microtek Laboratories
Anaheim, CA
+1 (714) 999-1616
Changzhou, China
+86 (519) 548-7805
[log in to unmask]
www.TheTestLab.com
________________________________
From: TGAsia [mailto:[log in to unmask]] On Behalf Of Chris Katzko
Sent: Tuesday, May 15, 2007 4:42 PM
To: [log in to unmask]
Subject: [TGA] 答复: Re: [TGA] active pad and dummy pad
Good question,. Is it Active/Dummy pad for PCB or for BGA component? In
the case of BGA, the Active pad would have electrical connections, the
Dummy pad would be for mechanical attachment and thermal enhancement.
C.B. Katzko, CTO
Meadville Group
e-mail [log in to unmask]
tel +86 21 5774 6907
fax +86 21 5774 0635
mobile +86 13817362590
JiaXing LIU <[log in to unmask]>
发件人: TGAsia <[log in to unmask]>
2007-05-15 16:25
请答复 给
Asia Committe Task Group Forum <[log in to unmask]>; 请答复 给
JiaXing LIU <[log in to unmask]>
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主题
Re: [TGA] active pad and dummy pad
Su
Active pad and dummy pad used in PCB processs or any other process?
Best reagrds
Jason Liu
Asia Pacific Strategic Sourcing
SDE
TRW Systems Consulting Services(Shanghai) Co., Ltd.
5F, 62 Building, 421 Hongcao Road,
Shanghai 200233, P.R.China
Tel:+86 21 6120 1166 or 6120 2266
Dir Tel:+86 21 6121 1811
Fax:+86 21 6120 7058
Mobile:+86 138 1895 6432
Email:[log in to unmask]
>>> Su Shibo <[log in to unmask]> 2007-5-15 15:49:45 >>>
Hi All,
Who knows those two items "Active pad" and "Dummy pad" in Chinese?
Many thanks,
Regards,
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