Ball-grid arrays (BGA) are IC packages, which place output pins in the form of a solder ball matrix. The traces of the BGA are generally fabricated on laminated substrates (BT-based) or polyimide-based films. Therefore, the entire area of substrates or films can be used to route the interconnection. BGA has the advantage of lower ground or power inductance thereby assigning ground or power nets via a shorter current path to PCB. Thermally enhanced mechanisms (heat sink, thermal balls, etc.) can be applied to BGA in order to reduce thermal resistance. The higher functional capabilities of the BGA package technology benefit high power and high speed ICs that require enhanced electrical and thermal performance. Compared with traditional SMT packages, the advantages of BGA are as follows:
Higher interconnect density Lower assembly cost Self-alignment during reflow Lower profile Ease of thermal and electrical management Ease of routing
Features
Pkg Type
PBGA
HSBGA
Cavity-Down BGAs
L2BGA
CSBGA
(1mm=39.37mil; 1mil=25.4um)
* The overall thickness is the sum of body and stand-off.
Reliability
Test Plan
All BGA packages are selected for temperature/humidity tests and temperature cycles are subject to the precondition process per JEDEC moisture LEVEL3 prior to environmental stress. Test criterion is zero defect out of 45 sampling units.
Temp/Humidity test
85ºC/85% RH, 1000 hr. (JEDEC 22-A101)
Temp cyclic test
-65ºC~150ºC, 1000 cycles/-55~125ºC, 1000 cycles for (L2BGA, CSBGA)