Cutting the ON-resistance and Qg to Lower Power Consumption Even Further

ROHM has added a new lineup, the R60xxMNx series, to its PrestoMOS^TM line featuring industry-fastest trr (reverse recovery time). PrestoMOS products sharply reduce switching losses by reducing trr by approximately 60% relative to standard super-junction MOSFETs, and have driven reduction of the power consumption of motor drivers and inverter applications in white goods, industrial equipment, and other areas. The new R60xxMNx series was developed so as to retain the fast trr of the preexisting R60xxFNx series, while further reducing the ON-resistance and Qg (total gate charge) with the goal of reducing losses. In general, there is a tradeoff between ON-resistance and Qg, but through ROHM's unique process technology and optimization, even higher levels for both were achieved simultaneously.

* PrestoMOS is a trademark of ROHM Co., Ltd.

Cutting Conduction Losses as Well as Switching Losses

The R60xxMNx series maintains the fast trr performance that is ROHM’s unique feature of PrestoMOS products, while greatly reducing the ON-resistance and Qg. In motor-driven application examples such as air conditioners with built-in inverters, power losses under light loading are reduced by about 56% compared with cases in which IGBTs are used. This has been highly effective in achieving the improvements in APF (annual energy consumption efficiency) in recent years. In addition to reduction of switching losses through faster trr, this is also due to cuts in conduction losses by lowering the ON-resistance, as well as smaller drive currents and faster operation through smaller Qg values.

FRD No Longer Needed in Inverter, Motor Driver Circuits

As explained above, trr values have been reduced by 60% compared with standard conventional super-junction MOSFETs. This means that the trr characteristic of the internal diode has been greatly improved. In particular, commutation losses due to regeneration currents in inverter circuits and motor driver circuits depend on the trr. In standard MOSFETs and IGBTs, the trr of the internal diode is slow and losses are large, and so two external FRDs (fast recovery diodes) are used. The PrestoMOS features fast trr, and so in addition to reduced losses, there is no need for two external FRDs.