PowerPoint 簡報

Cycle to Failure/Crack Initiation vs. Plastic Strain

and Energy Density (PBGA)

Leadless Chip Carrier, Y. H. Pao

PBGA, R.Darveaux

Use PBGA on

LCR case

1st

2nd Reflow

1st reflow

2nd

31.84

43.76

1.16%

0.88%

180

247

219

445

Prolong ratio = 445/219 = 2.03

Prolong ratio = 246/179 = 1.374

PBGA ==>

For SuperBGA:

1st reflow, eeq = 0.0153 ==> Nf=107.7 W=61psi ==> N0=128

2nd reflow, eeq = 0.0071==> Nf=772.4 W=25.33psi ==> N0=310

Prolong ratio = 7.17 Prolong ratio = 2.42