Justin,
Here is our footprint dimensions for 0603 both resistor and capacitor.
Some people increase capacitor pad because caps are usually taller components.
This gives you a taller toe fillet. But we have not found it necessary.
I agree we never attempt to put vias under 0603 and we have not felt comfortable
putting vias in 0603 and smaller components pads. We do alot vias in pads in 0805 and
larger.
Only once on a flex circuit .012 thick did we get away with vias in 0603 pads, very compact
circuit.
X = .9mm (0.036")
Y = 0.762mm (0.030")
G = 0.6mm (0.024")
pad center to pad center = 1.5mm (0.060")
Greg Scott
Cray Inc
Cad Designer
Safavi-Bayat Shahed wrote:
> Justin
> Putting vias between the pads!! That's something I never do with 0603 or
> most of other
> SMT parts. As a matter of fact I make sure that when the parts or shape
> created it has via keep out between
> the pads.
>
> Shahed Safavi-Bayat, C.I.D.
> Cad Designer
>
> 1035 Greenwood Blv. Suite 173
> Lake Mary Fl 32746
> mailto: [log in to unmask]
> Tel : (407)829-4440 ext.216
> Fax : (407)829-2213
>
> -----Original Message-----
> From: Braime, Justin [mailto:[log in to unmask]]
> Sent: Friday, August 31, 2001 5:14 AM
> To: [log in to unmask]
> Subject: [TN] 0603 land pattern debate
>
> Hi all,
> I have had some problems with a recent build with 0603 capacitors. The
> problem was that they were either very skewed or were soldered to one pad
> only (pulled off the other). The land pattern for the 0603 cap on this board
> was (I thought) fairly questionable. Using the IPC-SM-782 terminology, the
> current design is:
> X = 1.27 (0.05")
> Y = 0.508 (0.02")
> G = 1.016 (0.04")
> Our design dept's justification for this design is based on being able to
> put a via between the pads, but to my mind the G value is too borderline for
> consistent results. Also, I think the X value is a little on the high side -
> hence the skewing.
> I'm now trying to convince the design guys to adopt the IPC guidelines - at
> least the recommended G value anyway.
> I'd appreciate anybody else's thoughts on this!
> Incidentally, we placed 0402s on the same board with very few problems :)
>
> Thanks
>
> Justin Braime
>
> Senior Production Engineer
> Thales Instruments Ltd.
> 480 Bath Road
> Slough
> SL1 6BE
>
> Tel: 01628 604455 x 392
> Fax: 01628 662017
> Email: [log in to unmask]
>
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