SJ MOSFET (Super Junction MOSFET) is a type of superstructure MOSFET mainly used in high-voltage (600V-800V) applications. To address the issue of increased on-resistance with higher rated voltages, the SJ MOSFET arranges multiple vertical pn-junction structures between the D and S terminals. This results in low on-resistance while maintaining high voltage.

The structure of SJ MOSFET adds a superjunction diode to the trench MOSFET, effectively reducing switching losses and reverse recovery time, thereby improving efficiency and reliability.

For conventional VDMOS devices, RDS(ON) and BV are contradictory. To increase BV, the EPI doping concentration must be reduced, inevitably increasing the on-resistance. However, SJ MOSFETs increase the doping concentration of NEPI while adding a P-column to form a larger PN junction. This creates a thicker PN depletion layer during device reverse bias, achieving high isolation voltage, thereby breaking the limit of the original VDMOS RDS(ON)/BV.

Characteristics of SJ MOSFETs

SJ MOSFETs have the advantages of low conduction loss, high current drive capability, low gate charge, low turn-on voltage, fast switching speed, and 100% avalanche energy breakdown testing. They are generally suitable for motor drive systems, inverter systems, power management systems, and high-power applications.

Taking the example of high-power power supply applications, SJ MOSFETs are widely used in solar inverters, electric vehicle drive power supplies, industrial power supplies, etc.

In solar inverters, SJ MOSFETs can significantly improve system efficiency and reliability. In electric vehicle drive power supplies, the high switching speed and low switching losses of SJ MOSFETs provide stable and efficient power support for vehicle acceleration and driving. In industrial power supplies, the low conduction loss and low switching loss of SJ MOSFETs provide stable and efficient power for various industrial equipment.

Here, we recommend VBsemi's Super Junction MOSFET models:

Advantages of VBsemi's Super Junction MOSFETs:

• High efficiency and strong stability

• Low internal resistance, low power consumption, low temperature rise

• Suitable for hard and soft switching (PFC and LLC)

• Easy to use, can be quickly designed for PFC and PWM stages

• Suitable for a variety of applications and power requirements