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Stencil Aperture Aspect Ratio

Bruce

#24848

Stencil Aperture Aspect Ratio | 17 June, 2003

What is the correct formula for Aspect Ratio?

Thanks

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#24850

Stencil Aperture Aspect Ratio | 17 June, 2003

Consider searching the fine SMTnet Archives for discussion, for instance: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=7065

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RDR

#24851

Stencil Aperture Aspect Ratio | 17 June, 2003

Aspect ratio = width of aperture divided by height. E.G. 6 mil stencil at 9 mil wide = aspect ratio of 1.5. Value should be 1.5 min.

Area ratio - use when length and width of pad are roughly same dimension like for BGAs and 0805 and smaller R-nets

this is the ratio of contact area of aperture opening and the surface area of the aperture walls. E.G. 30 mil aperture at 6mils thick gives area ratio of 1.25 Value should be greater than .66

Russ

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#24944

Stencil Aperture Aspect Ratio | 24 June, 2003

Bruce, I have a spread sheet, in Excel, that helps in determining stencil thickness, based on smallest aperture size. If you are interested, I can email you this.

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Mark Coplan

#25017

Stencil Aperture Aspect Ratio | 30 June, 2003

If you would email me your aperature ratio on the excell spreadsheet I would be most grateful Thanks,

Mark

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John

#25148

Stencil Aperture Aspect Ratio | 11 July, 2003

do you mind sending me the excel file also? 4699j@hotpop.com

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KS Wong

#25193

Stencil Aperture Aspect Ratio | 16 July, 2003

pls send me a copy too. thks!

kietsiongwong@pg.slr.com

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