News: Microelectronics
4 February 2021
ROHM’s SiC MOSFETs used by MidNite Solar
Power semiconductor maker ROHM Semiconductor says that its silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) are being utilized by MidNite Solar Inc of Arlington, WA, USA (a producer of alternative energy products) to drive efficiency and reduce system cost in four products new to the US market: the Hawkes’s Bay 600VDC-to-48VDC 6000W MPPT (maximum power point tracking) solar charge controller, powerful Barcelona dual MPPT charge controller, MNB17 advanced battery-based charger/inverter, and 120/240V Rosie inverter/charger.
“SiC power devices offer vastly improved energy efficiency over the silicon parts they replace, and the cost premium has come down significantly, enabling a wider range of applications to benefit from these devices for better system performance and value,” says Ming Su Ph.D., technical marketing manager at ROHM Semiconductor.
“Silicon carbide solves a key challenge,” explains MidNite Solar’s principal owner & engineering manager Robin Gudgel. “Regular silicon MOSFETs have a very slow body diode. Therefore, trying to make an inverter work as a charger where it must run bidirectionally is very difficult,” he adds. “We were looking at an IGBT [insulated-gate bipolar transistor] pair in combination with another diode, but silicon carbide is such a good solution, and ROHM’s devices did not require any significant design changes.”
MidNite Solar has incorporated ROHM’s 60mΩ RDS(on) (on-resistance) SiC devices and newer 30mΩ RDS(on) products in its new solar product ranges. Gudgel expects reliability to be excellent, as the design is running cool. Driving the parts should be simple, as ROHM also supplies the gate drivers.
