Typical via size?

Discussion:

Typical via size?

richmogd

2007-05-23 01:45:44 UTC

Hi All,

It's been a while since I've mad a PCB, so I want to get an idea of
what a typical via size should be. I'm being told by a PCB
manufacturer that the pad needs to be 0.6mm bigger than the hole (and
the hole is ideally 0.4mm). The tracks are all 0.2mm (the signal
tracks at least). With a clearance of 0.2mm on either side, that means
each via will take up 1.4mm space on the board. Does this sound
strange to anyone else? I'm not sure I could actually lay out the
board with vias of this size.

Thanks,

Glenn.

Please read the Kicad FAQ in the group files section before posting your question.
Please post your bug reports here. They will be picked up by the creator of Kicad.
Please visit http://www.kicadlib.org for details of how to contribute your symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the kicad-devel group at http://groups.yahoo.com/group/kicad-devel

Robert Kondner

2007-05-23 02:11:07 UTC

Permalink

I typically run .15 traces and spaces with .5mm vias using .3mm holes.

That is a little light on the via ring, I have to tell the fab shop NOT to
oversize the drill hole. This does result in vias plating solid but that is
ok with me.

(I typically work in mils and my actual numbers are 6 mil trace clearance,
20 mil via, 12 mil drill. If I have room I use a 24 mil via which is plenty
or room.)

I run these boards through Advanced Circuits which does not charge extra
for these rules. If I go any tighter then I would have to use a different
shop and pay much more money.

Bob Kondner

-----Original Message-----
From: kicad-users-***@public.gmane.org [mailto:kicad-users-***@public.gmane.org] On
Behalf Of richmogd
Sent: Tuesday, May 22, 2007 9:46 PM
To: kicad-users-***@public.gmane.org
Subject: [kicad-users] Typical via size?

Hi All,

It's been a while since I've mad a PCB, so I want to get an idea of
what a typical via size should be. I'm being told by a PCB
manufacturer that the pad needs to be 0.6mm bigger than the hole (and
the hole is ideally 0.4mm). The tracks are all 0.2mm (the signal
tracks at least). With a clearance of 0.2mm on either side, that means
each via will take up 1.4mm space on the board. Does this sound
strange to anyone else? I'm not sure I could actually lay out the
board with vias of this size.

Thanks,

Glenn.

Please read the Kicad FAQ in the group files section before posting your
question.
Please post your bug reports here. They will be picked up by the creator of
Kicad.
Please visit http://www.kicadlib.org for details of how to contribute your
symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the
kicad-devel group at http://groups.yahoo.com/group/kicad-devel
Yahoo! Groups Links

Please read the Kicad FAQ in the group files section before posting your question.
Please post your bug reports here. They will be picked up by the creator of Kicad.
Please visit http://www.kicadlib.org for details of how to contribute your symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the kicad-devel group at http://groups.yahoo.com/group/kicad-devel

richmogd

2007-05-23 02:51:36 UTC

Permalink

Hi Bob,

Thanks for that - these sizes seem much more reasonable, not too far
off what I've got. I can adjust the via sizes to match without too
much trouble to the board layout.

Also, I like the freedfm services that Advanced Circuits offer!

I'll try to work out a solution with my current manufacturer, but
they're talking about doubling the size of my vias, so I don't think
it's an option for my board if they can't do what AC does.

Best Regards,

Glenn.

Post by Robert Kondner
I typically run .15 traces and spaces with .5mm vias using .3mm holes.
That is a little light on the via ring, I have to tell the fab shop NOT to
oversize the drill hole. This does result in vias plating solid but that is
ok with me.
(I typically work in mils and my actual numbers are 6 mil trace clearance,
20 mil via, 12 mil drill. If I have room I use a 24 mil via which is plenty
or room.)
I run these boards through Advanced Circuits which does not charge extra
for these rules. If I go any tighter then I would have to use a different
shop and pay much more money.
Bob Kondner
-----Original Message-----
Behalf Of richmogd
Sent: Tuesday, May 22, 2007 9:46 PM
Subject: [kicad-users] Typical via size?
Hi All,
It's been a while since I've mad a PCB, so I want to get an idea of
what a typical via size should be. I'm being told by a PCB
manufacturer that the pad needs to be 0.6mm bigger than the hole (and
the hole is ideally 0.4mm). The tracks are all 0.2mm (the signal
tracks at least). With a clearance of 0.2mm on either side, that means
each via will take up 1.4mm space on the board. Does this sound
strange to anyone else? I'm not sure I could actually lay out the
board with vias of this size.
Thanks,
Glenn.
Please read the Kicad FAQ in the group files section before posting your question.
Please post your bug reports here. They will be picked up by the creator of
Kicad.
Please visit http://www.kicadlib.org for details of how to

contribute your

Post by Robert Kondner
symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the
kicad-devel group at http://groups.yahoo.com/group/kicad-devel
Yahoo! Groups Links

Please read the Kicad FAQ in the group files section before posting your question.
Please post your bug reports here. They will be picked up by the creator of Kicad.
Please visit http://www.kicadlib.org for details of how to contribute your symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the kicad-devel group at http://groups.yahoo.com/group/kicad-devel

Magnus Beischer

2007-05-23 20:56:45 UTC

Permalink

Have a look at this table:
http://www.multek.se/engelska/produktionsunderlag-en/kapabilitet-en/monsterklasser-en/

A good graphical view of the different dimensions that affect the cost
for your board. So far we have only needed to use class M5 for our
boards with 0.3 mm vias. M5 shouldn't be a problem for any PCB manufacturer.

I don't think that M5 - M8 is a industry standard in any way, but could
be used as cost guideline for anyone designing a board.

// Magnus

Post by richmogd
Hi All,
It's been a while since I've mad a PCB, so I want to get an idea of
what a typical via size should be. I'm being told by a PCB
manufacturer that the pad needs to be 0.6mm bigger than the hole (and
the hole is ideally 0.4mm). The tracks are all 0.2mm (the signal
tracks at least). With a clearance of 0.2mm on either side, that means
each via will take up 1.4mm space on the board. Does this sound
strange to anyone else? I'm not sure I could actually lay out the
board with vias of this size.
Thanks,
Glenn.
Please read the Kicad FAQ in the group files section before posting your question.
Please post your bug reports here. They will be picked up by the creator of Kicad.
Please visit http://www.kicadlib.org for details of how to contribute your symbols/modules to the kicad library.
For building Kicad from source and other development questions visit the kicad-devel group at http://groups.yahoo.com/group/kicad-devel