We have been asked by designers to provide guidelines for BGA components on a PCB.
Regardless of the BGA packaging size you must consider what size of pads are required and how many connections are needed to be brought out of the package.
This then should be compared with our current Classification Table on our PCB Design Guidelines – Classification page.
Poolable Options
To ensure the best price your board needs to be poolable.
Therefore, with reference to BGA components please bear in mind the following minimum Poolable values below (Class 8E):
- (TT) Track to Track isolation gap is 0.100mm (4mil).
- (TP) Track to Pad isolation gap is 0.100mm (4mil).
- (TW) Track Width is 0.100mm (4mil).
- Via Holes under the device – the smallest finished Via Hole Size is 0.10mm (4mil).
- Min. Outer Layer Pad size is 0.400mm (16mil) for a 0.10mm (4mil) finished hole size.
(Min. Outer Layer Pad size is the finished hole size + the plating (0,10mm) + 2 x OAR (Outer Annular Ring)) - Min. Inner Layer Pad size is 0.450mm (18mil) for a 0.10mm (4mil) finished hole size.
(Min. Inner Layer Pad size is the finished hole size + the plating (0,10mm) + 2 x IAR (Inner Annular Ring))
Non-Poolable Options
For Non-Poolable designs the minimum values are below (Class 9E):
- (TT) Track to Track isolation gap is 0.090mm (3.5mil).
- (TP) Track to Pad isolation gap is 0.090mm (3.5mil).
- (TW) Track Width is 0.090mm (3.5mil).
- Via Holes under the device – the smallest finished Via Hole Size is 0.10mm (4mil).
- Min. Outer Layer Pad size is 0.400mm (16mil) for a 0.100mm (4mil) finished hole size.
- Min. Inner Layer Pad size is 0.400mm (16mil) for a 0.100mm (4mil) finished hole size.
However, you should be aware that using these values the price will increase.
