“The kit is inspired by a design created by PI’s on-line support engineers in collaboration with the ETH Zurich aCentauri team, whose ‘Silvretta’ challenger-class car is using the design to maximise efficiency in its auxiliary power supply,” according to the company. “We are providing this reference kit to help young engineers take advantage of the latest, most energy-efficient technologies, such as PowiGaN, in their designs.”
The assembled open frame PSU in the kit, RDK-85SLR, delivers 12V at 3.84A (46W) continuously and peaks up to 6.67A (80W) from an input of 100 to 150Vdc.
aCentauri 2025
“We proved GaN’s reliability in the Bridgestone World Solar Challenge in 2023,” said 2023 aCentauri team electrical engineer Aaron Griesser. “We achieved 95% efficiency across an output range of 5 to 60 W – the scrutineering judges were astounded to see an auxiliary power supply without a heatsink.”
It is an isolated fly-back design using the company’s 900V rated INN3990CQ IC, and based on its earlier RDR-85SLR reference design which used 750V GaN. Creepage and clearance are to IEC-60664 parts 1 and 4. SMD components used are AEC-Q automotive-qualified.
The kit is also available for purchase, and includes a sample power supply, four InnoSwitch3-AQ ICs and an unpopulated PCB.
A supporting 51 page design document can be downloaded without payment, which includes transformer build instructions, schematics, a PCB layout guide, and thermography.
The Bridgestone World Solar Challenge starts on 24 August, and this year 37 student teams will compete across the Outback. PI is a sponsor of the aCentauri team.
Find the PSU kit on this Power Integrations web page, and the supporting document here, which is worth a look as PI reference designs are among the most thorough, Ed.
