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"Gallium nitride power transistors, which can replace silicon
metal oxide semiconductor field-effect transistors, enable
much higher-frequency switching with greater efficiencies."
Benoit GORAL, Signal and Power
Integrity Engineer, Thales
Benoit Goral holds a PhD from Université
Paris-Saclay. His research, in collaboration
with Thales Communications and Security,
focuses on power integrity and power
rail design optimization. Since 2017, he
has worked with Thales SIX GTS France,
where he is in charge of high-speed,
complex PCB design; high-speed serial link
development; DDRx interface simulation
and optimization; and equipment-level
EMC design and troubleshooting.
Many of our products are avionics and tactical communication related, so our designs
must work reliably for many years in harsh environments and extreme temperature
ranges. For that reason, we use proven parts rather than leading-edge technologies.
Our critical constraints are size, weight, and power. Cost is not so important because
we manufacture highly specialized devices with low production runs.
One challenge we face is power distribution network (PDN) size. On a digital board,
the PDN that distributes power to components can take as much as 30 percent of
the surface of the printed circuit board (PCB). To make the device smaller, we must
optimize the PDN, but conflicting trends make this difficult. For example, we can
reduce the size of the PDN by using an integrated circuit (IC) that implements up to
eight DC-to-DC converters in one IC package. The resulting component is not a digital
component but an electronic power component that is a single package with one
power input and up to eight different power rails on the output side. This approach, in
combination with much smaller decoupling capacitors in a 0201-inch package size or
smaller, helps reduce overall PDN size.
System-on-a-Chip Components Create
PDN Challenges
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