On Dec 28, 5:01 pm, Rich Webb <bbew...@mapson.nozirev.ten> wrote:
> On Wed, 28 Dec 2011 14:26:46 -0700, hamilton <hamil...@nothere.com>
> wrote:
>
>
>
>
>
>
>
>
>
> >On 12/28/2011 11:45 AM, cassiope wrote:
> >> On Dec 28, 6:57 am, hamilton<hamil...@nothere.com>  wrote:
> >>> I have noted that many PCB shops around the globe now offer minimum 15
> >>> mil drill size.
>
> >>> What is the most reliable and smallest annular ring for a via with a 15
> >>> mil hole ?
>
> >>> Also, does anyone have a link for a LFBGA100 layout ?
>
> >>> This is my first try on a BGA layout, any advice or suggestions would be
> >>> welcome.
>
> >>> Thanks
>
> >>> don
>
> >I got an email from advanced circuits in Colorado:
>
> >Advanced Circuits requires that vias with connecting traces have a pad
> >that is 10 mils larger than their drill, and component through holes
> >with electrical connections have a pad that is 14 mils larger than their
> >drill. Tooling holes with no electrical connections may have 0 mil
> >annular ring.
>
> >I.e  a 0.015 via drill must have at least a 0.025" pad over it
>
> >I.e  a 0.070 component drill must have at least a 0.084 pad over it if
> >there is a trace attached.
>
> >Do other PCB houses have the same requirements ??
>
> Here's Sunstone's manufacturing requirements:
> <http://www.sunstone.com/pcb-capabilities/manufacturing-capabilities.aspx>
>
> There's a good non-manufacturer-specific discussion of PCB guidelines at
> <http://alternatezone.com/electronics/pcbdesign.htm> by the same gent
> who does thehttp://www.eevblog.com/. Both are much worth checking out.
>
> --
> Rich Webb     Norfolk, VA

I looked at the tutorial and very early in I realized that it is a bit
out of date...

"The majority of electronic components were (and still are)
manufactured with imperial pin spacing".

Uh, since when?  Not only do most of the parts I work with have metric
dimensions, some don't even bother to include imperial dimensions on
the mechanical drawing in the data sheet.

Otherwise I think this tutorial is a fairly good starting point.  I do
recommend that no single reference on PCB design and construction be
taken as gospel.  I see too many differences of opinion and they all
can't be right.

Rick

On Wed, 28 Dec 2011 14:26:46 -0700, hamilton <hamilton@nothere.com>
wrote:

>On 12/28/2011 11:45 AM, cassiope wrote:
>> On Dec 28, 6:57 am, hamilton<hamil...@nothere.com>  wrote:
>>> I have noted that many PCB shops around the globe now offer minimum 15
>>> mil drill size.
>>>
>>> What is the most reliable and smallest annular ring for a via with a 15
>>> mil hole ?
>>>
>>> Also, does anyone have a link for a LFBGA100 layout ?
>>>
>>> This is my first try on a BGA layout, any advice or suggestions would be
>>> welcome.
>>>
>>> Thanks
>>>
>>> don
>
>
>I got an email from advanced circuits in Colorado:
>
>Advanced Circuits requires that vias with connecting traces have a pad
>that is 10 mils larger than their drill, and component through holes
>with electrical connections have a pad that is 14 mils larger than their
>drill. Tooling holes with no electrical connections may have 0 mil
>annular ring.
>
>I.e  a 0.015 via drill must have at least a 0.025" pad over it
>
>
>I.e  a 0.070 component drill must have at least a 0.084 pad over it if
>there is a trace attached.
>
>
>Do other PCB houses have the same requirements ??

Here's Sunstone's manufacturing requirements:
<http://www.sunstone.com/pcb-capabilities/manufacturing-capabilities.aspx>

There's a good non-manufacturer-specific discussion of PCB guidelines at
<http://alternatezone.com/electronics/pcbdesign.htm> by the same gent
who does the http://www.eevblog.com/. Both are much worth checking out.

-- 
Rich Webb     Norfolk, VA

On 12/28/2011 11:45 AM, cassiope wrote:
> On Dec 28, 6:57 am, hamilton<hamil...@nothere.com>  wrote:
>> I have noted that many PCB shops around the globe now offer minimum 15
>> mil drill size.
>>
>> What is the most reliable and smallest annular ring for a via with a 15
>> mil hole ?
>>
>> Also, does anyone have a link for a LFBGA100 layout ?
>>
>> This is my first try on a BGA layout, any advice or suggestions would be
>> welcome.
>>
>> Thanks
>>
>> don

I got an email from advanced circuits in Colorado:

Advanced Circuits requires that vias with connecting traces have a pad
that is 10 mils larger than their drill, and component through holes
with electrical connections have a pad that is 14 mils larger than their
drill. Tooling holes with no electrical connections may have 0 mil
annular ring.

I.e  a 0.015 via drill must have at least a 0.025" pad over it

I.e  a 0.070 component drill must have at least a 0.084 pad over it if
there is a trace attached.

Do other PCB houses have the same requirements ??

They also suggest this web resource:

http://pcdandf.com/cms/magazine/95/3760

don

On Dec 28, 6:57=A0am, hamilton <hamil...@nothere.com> wrote:
> I have noted that many PCB shops around the globe now offer minimum 15
> mil drill size.
>
> What is the most reliable and smallest annular ring for a via with a 15
> mil hole ?
>
> Also, does anyone have a link for a LFBGA100 layout ?
>
> This is my first try on a BGA layout, any advice or suggestions would be
> welcome.
>
> Thanks
>
> don

Maybe you haven't looked very far -- Advanced PCBs is touting their
3mil (finished) hole size.
I'm sure there are many others.  Of course, it will cost you more than
a 15mil process.
You'll have to look at each fabricator to see what kind of annular
ring they require.