Page 14 - PEN eBook NOVEMBER 2022

DESIGN
different power semiconductor technologies are used
in the same design (Figure 5).
MOSFET packages can be thermally bonded to a cold
plate in several ways. Still, the most straightforward
and most effective approach is to place a single
thermally conductive gap filler between a MOSFET and
its heatsink. This approach also has the advantage
of allowing the production process to be fully
automated. While the gap filler can provide sufficient
electrical isolation, for extra safety, an additional
isolation foil can be used to provide further electrical
isolation without significant deterioration in thermal
performance.
HOW TO ADDRESS OBC POWER
DENSITY EVOLUTION
Infineon collaborated with Silicon Austria Labs to
develop a 7-kW automotive OBC design to demonstrate
high power density utilizing SiC and TSC package
innovation.
This is a single-phase, isolated, bidirectional charger
Figure 6: Tiny Power Box OBC developed collaboratively by with an integrated low-voltage 2.4-kW, 12-V output.
Silicon Austria Labs, Infineon, and other partners The reference design, which occupies a volume of
about 3.2 kW/L (including the case and connectors),
and they also have a Kelvin source pin to control uses Infineon’s TSC 750-V SiC MOSFETs to achieve an
*
efficiency (Figure 4). overall peak efficiency of about 97%, including the PFC
and C LLC converters (Figure 6). 1
ASSEMBLY CONSIDERATIONS
Heat-generating MOSFET devices and heatsinks are Toward an even high-power–density class, Infineon
generally placed on the top side of a PCB alongside collaborated with the Power Electronic Systems
other low-profile components. In contrast, taller Laboratory, ETH Zürich, on a super-high–density OBC
devices are typically placed on the underside of the design based on GaN HEMT technology. 2
board. Infineon’s HDSOP devices are designed to have
a uniform height of 2.3 mm, simplifying cold plate By combining advanced control and modulation
attachment and removing the need for machining. This schemes with the superior behavior of these devices
also allows optimized heatsinks to be used, even where under different switching conditions, the uncased
Figure 7: GaN HEMT-based OBC designed by ETH Zurich and Infineon
* Coming soon. For product availability or sample requests contact our support
14 NOVEMBER 2022 | www.powerelectronicsnews.com
DESIGN
power density of the final charger design, which
measured 17.8 × 400 × 140 mm , was 10 kW/L. Nov. 15–18, 2022: Join us at electronica in Munich in Hall C3,
3
Booth 502, or digitally
This feasibility study shows effectively that there is
a lot of further power density increase with the right Experience Infineon at electronica 2022, taking place at the
technology/package/topology combination achievable. Trade Fair Center in Messe München, from Nov. 15 to 18.
Of course, while there are some topics to solve and
enable such technology in mass production, this is the As a leader in IoT and power systems, we have the
key focus of Infineon R&D departments together with technologies, innovative drive, collaborative spirit, and agility
key stakeholders in the industry. We all look forward to drive decarbonization and digitalization. Various hands-on
to seeing the successful market introduction of GaN demos will provide impressive proof of the many ways we have
in the coming years, where the need for higher power teamed up with customers and partners to accelerate the
density could be solved with designs like that. delivery of concrete, value-adding answers to today’s green and
digital transformation challenges.
SUMMARY
Reduction in weight and volume will be the key Also on stage will be our revolutionary and extensive wide-
challenges supporting the range increase of EVs in the bandgap portfolio. Spanning GaN and SiC technologies, it brings
future. Small and lightweight OBCs will be part of this an unmatched quality to efficiency-critical applications that feed
evolution. into the decarbonization and digitalization trends.
While practical OBCs with a power density of 10 kW/L We look forward to meeting with you face to face with you and
may not yet be achievable, Infineon has demonstrated reconnecting after such a long gap. Visit us in Hall C3 at Booth
how its innovative WBG devices and packaging 502 for a holistic and unique Infineon-brand experience.
technologies can be combined to produce prototype
reference designs with power densities. With the fast We also invite you to visit our digital
move toward higher EV efficiencies, platform, the perfect hub to dive
the need for higher power density deeper into the various technologies we
in OBCs will be further accelerated will be showcasing at electronica 2022
than previously thought. — both during and after the event. Scan
the QR code to visit our electronica
For more information, please scan 2022 website and find out more. electronica
the QR code to visit our webpage for
OBC applications OBC solutions.
For More Information
▶ Mentin, C. “Project Tiny Power Box.” Silicon Austria Labs.
1
▶ Kasper et al. (2022). “Next Generation GaN-based Architectures: From 240W USB-C Adapters to 11kW EV
2
On-Board Chargers with Ultra-high Power Density and Wide Output Voltage Range.” PCIM Europe 2022;
International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and
Energy Management, pp. 1–10, doi: 10.30420/565822004.
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