Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Should I panic over .5mm pitch BGA?

Views: 4107

#36418

Should I panic over .5mm pitch BGA? | 31 August, 2005

Hi,

We have a new part we need to mount, and it's a .5 mm pitch BGA with .3 mm diameter pads. That's a lot smaller than we have done before, and we currently use 1 mm pitch BGA's with .5 pads.

Has anyone does .5 mm pitch BGA's and what needs to be done on the stencil to handle that? We use 5 thou with 1:1 reduction currently. Laster cut.

Regards,

Grant

reply »

#36419

Should I panic over .5mm pitch BGA? | 31 August, 2005

BGA's with pitch < 1.0 mm we use square aperture size 1:1 and 0.127 mm (5 thou) stencil thickness. Currently we produce 0.75 mm pitch & 0.8 mm pitch uBGA's without any problem. Maybe You can try this?

reply »

PWH

#36427

Should I panic over .5mm pitch BGA? | 31 August, 2005

Agree with Siverts. We do a build that has 0.3mm pad diamter BGA (0.8mm pitch - distance from pad center to pad center) and 0.5mm dia. BGA balls. Stencil specs. are: 5 mil. thickness, square BGA pad aps. (1:1, 0.3mm square aps), laser cut. Seems to work very well. Inspect all pads post print to make sure they have coverage!!!!!

reply »

aj

#36430

Should I panic over .5mm pitch BGA? | 31 August, 2005

Grant,

We run the exact same process as you described.

5 thou stencil, 1:1 ratio

aj

reply »

Jason Fullerton

#36431

Should I panic over .5mm pitch BGA? | 31 August, 2005

We are using one BGA that has 7 mil bumps on a 20 mil pitch. We use the manufacturer's recommended pad and aperature layout, which is an 11.8 mil square overprint on a 6 mil land. At 11.8 square, you need to use a 4 mil laser cut or a 5 mil e-form stencil to efficient paste release.

This is an excellent resource on uBGAs and design considerations: http://www.national.com/an/AN/AN-1112.pdf

This message was posted via the Electronics Forum @

reply »

lsmith

#36471

Should I panic over .5mm pitch BGA? | 1 September, 2005

I have recently tried electroform (100% nickel) stencils. Expensive but awesome paste release.

5 mil foil 10 - 15% aperture reduction for gasketing

This message was posted via the Electronics Forum @

reply »

convection smt reflow ovens

ICT Total SMT line Provider