Datasheet
IBM PowerPC 750GX RISC Microprocessor
DD1.X
The qualification testing included a lead-free water soluble solder paste with type 3 mesh size (-325/+500).
The solder alloy is 95.5% Sn, 4.0% Ag, and 0.5% Cu, with a 90% metal loading. The paste viscosity range is
600 to 800 Kcps. The thickness of the stencil is 4 mils and the aperture size is 23 mil diameter. The target
solder paste volume range is between 1400 to 2000 cubic mils. Achieving the correct paste volume is neces-
sary for eliminating solder shorts and producing high reliability solder joints. The actual solder paste volume
from the qualification build ranged from 1750 to 2000 cubic mils.
Another change is the JEDEC Moisture Sensitivity Level, which is MSL 3 for the reduced-lead package.
Storage and assembly protocols should be modified accordingly.
4.1.1.3 Board Layout Considerations
As shown in Table 4-1, the smaller size of the reduced-lead ball is matched by a smaller pad on the module
substrate, and requires a smaller recommendation for card pad size (for the ball end of the dogbone), solder
mask opening, and solder screen diameter.
4.1.2 Package Mechanical Drawings
Dimensions and Signal Assignments
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750GX_ds_body.fm SA14-2765-02
September 2, 2005
IBM [ IBM ]
