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AN4407

Conclusions

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Conclusions

The introduction of the fourth (driving) pin strongly improves the dynamic performance of

Power MOSFET devices, which is even more evident when the switching current levels and

the output power levels are higher during both device turn-off and turn-on. The test results

show that the MDmesh™ M5 technology device assembled with the driving source pin

provides significant benefits when the switching current is higher than approximately 10 A at

turn-off, but the advantages are present at all power levels. Different increments in efficiency

were measured for different power levels, and in a market where power levels are always

increasing, each small efficiency improvement represents a large advantage for energy

saving systems demanded in today’s very competitive market.

For our demo board, the energy saving was almost 7 W at maximum output power (2 kW).

The most important benefit, however, lies in the thermal behavior: in fact, a small magnitude

of power loss is translated into a difference of many degrees (around 20°C) on case

temperatures for the power device. Lower working temperatures allow the use of smaller

heat sinks which occupy less area on board or, more importantly, can increase the reliability

of the entire system.

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References

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applications, and design”, Second edition, John Wiley & Sons, New York, 1995.

2.

Won-suk Choi, Dong-kook Son, Markus Hallenberger and Sungmo Young"Driving and

Layout Requirements for Fast Switching MOSFETs.”

3.

Y. Xiao, H. Shah, T. P. Chow and R. J. Gutmann"Analytical Modeling and Experimental

Evaluation of Interconnect Parasitic Inductance on MOSFET Switching Characteristics”

4.

Jon Mark Hancock, "Super junction FETs Boost Efficiency in PWMs", in Power

Electronics Technology, July 2005, pp. 20-29.

5.

G.Sorrentino, M. Melito, F. Chimento, S. Musumeci, A. Raciti "SiC Diodes and

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6.

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7.

STMicroelectronics, AN2951 "3 kW fixed-off-time (FOT) power factor correction”, June

2010.