MOSFETs enhance power density of high-efficiency converters

As super-junction MOSFETs, the company claims that the new devices - in voltage ratings from 950-1,050V - deliver switching performance with lower on-resistance (R_DS(ON)) and higher current rating per die area compared to ordinary planar MOSFETs. They enable designers to enhance efficiency, as well as increase power density by using fewer parallel components, in converters for high-power equipment such as telecom and data centre servers powered from high bus voltages, industrial welders, plasma generators, high-frequency induction heaters, and X-ray machines.

With the fast-recovery body diode, the new devices enable higher efficiency in ZVS LLC resonant converters, which are chosen for applications that require high efficiency over a wide input-voltage range. Other types of bridged converters, as well as boost DC/DC converters for battery charging, also benefit from the reduced losses and enhanced dynamic performance of these devices. Compared with currently available VHV fast-diode MOSFETs, the DK5 devices from ST combine the best reverse-recovery time (trr) and lowest MOSFET gate charge (Qg) and RDS_(ON), with the favourable output and input capacitances (C_oss, C_iss) of a super-junction device.

The DK5 family extends ST’s VHV super-junction portfolio, which includes devices from 800-1,500V, adding six new parts in TO-247, TO-247 Long-Lead, Max247, and ISOTOP power packages. Volume production has already started for the STWA40N95DK5, STY50N105DK5, and STW40N95DK5.