Page 25 - Chip Scale Review_November December_2021-digital

Figure 10: a) (left) Self-inductance values at 100MHz for both 100-lead MaXQFP
and 100-lead QFP; and b) (right) Self-capacitance values at 100MHz for both 100-
lead MaXQFP and 100-lead QFP.
resistance is almost identical between these two parts as shown in
Figure 9. However, because of a smaller body size, the 100-lead
MaxQFP shows lower signal net self-inductance and capacitance
values at 100MHz than those of the 100-lead QFP (Figure 10).
As a result of lower self-inductance and capacitance, the 100-lead
MaxQFP package is expected to have less return loss for signal
nets than the 100-lead QFP, as indicated in Figure 11. Overall, the
100-lead MaXQFP package has improved electrical performance
as compared to an equivalent lead count QFP, driven both by the
smaller body size, and the addition of the short-electrical-path J-leads.

Summary
The semiconductor industry is in a constant drive for
miniaturization, reduced cost, increased performance, and
improved quality and reliability. This drive persists even in
spaces where more mature packaging technologies reign.
MaxQFP is a new package aimed precisely towards these
objectives.
Often, the goal of package miniaturization can only be
accomplished by increasing the fragility of the package
and by driving ever-finer dimensions on the PCB. Notably,
MaxQFP performs even in extreme environmental use cases as
encompassed by the AEC Grade 1 and Grade 0 standards and
can be used even with standard PCB design rules.

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