BUK9J0R9-40H – A Super Junction MOSFET with Low On-State Resistance

BUK9J0R9-40H – A Super Junction MOSFET with Low On-State Resistance


A MOSFET known as a metal-oxide-semiconductor-field-effect transistor is a special type of field-effect transistor which has an insulated gate where in this case the voltage determines the conductivity of the device. Just like conventional transistors, they are also used for switching and amplifying signals.

MOSFETs are now more commonly used in digital and analog circuits than BJTs (bipolar junction transistors) mostly because of their power efficiency. MOSFET’s are power efficient because the output is controlled by an input voltage instead of an input current. Electronics today are gearing towards low-power usage and MOSFETs seems to offer that over the BJTs.

There are several types of MOSFETS, and Super-Junction MOSFETs is a type of power transistor that is becoming mainstream lately. They are well-suited for high-speed operation at lower to immediate power levels as compared to IGBTs or the SiC-MOSFETs as shown in the graph below.

After the first super-junction MOSFETs was introduced commercially by Siemens in Germany (1999), super-junction MOSFETs in recent years are becoming the leading representative of MOSFETs for high voltages.

Nexperia, a global leader in Discrete, Logic and MOSFETs devices have introduced an automotive-focused super-junction MOSFETs in an electrically and thermally efficient LFPAK56E package called the BUK9J0R9-40H.

The Nexperia LFPAK56 package provides a genuine alternative to DPAK and D2PAK solutions. It will allow a considerable amount of space to be saved as compared to traditional D2PAK and DPAK solutions and offers designers flexibility and reliability without compromising thermal performance.

The BUK9J0R9-40H features low RDS (on) of just 0.9 mΩ and can handle a maximum load current of 220 A at 40 V for applications switching up to 1.2 kW power, providing a cost and power efficient solution. The low RDS (on) and maximum current rating of 220 A of this newly launched MOSFETs seems to be the highest ever achieved in a power-S08 footprint device for use in the automotive sector.

The BUK9J0R9-40H is simply an N-channel 40 V, 0.9 mΩ logic level MOSFET in an LFPAK56E package. Just like every other super-junction MOSFET, the MOSFETs can also be operated in parallel for higher current applications.

Below are some of the super junction MOSFETs featuers:

  • Fully automotive qualified to AEC-Q101:
    • 175 °C rating suitable for thermally demanding environments
  • Trench 9 Superjunction technology:
    • Reduced cell pitch enables enhanced power density and efficiency with lower RDSon in the same footprint
    • Improved SOA and avalanche capability compared to standard TrenchMOS
    • Tight VGS(th) limits allow easy paralleling of MOSFETs
  • LFPAK Gull Wing leads:
    • High Board Level Reliability absorbing mechanical stress during thermal cycling, unlike traditional QFN packages
    • Visual (AOI) soldering inspection, no need for expensive x-ray equipment
    • Easy solder wetting for good mechanical solder joint
  • LFPAK copper clip technology:
    • Improved reliability, with reduced Rth and RDSon
    • Increases maximum current capability and improved current spreading

The BUK9J0R9-40H will easily find applications in 12V automotive systems, high-performance power switching circuitry, transmission control system, inductive load controls like pumps, motors, and others, reverse polarity protection and DC/DC switching converters.

More information about the super junction MOSFETs can be found on the product page, and the product datasheet can be download here.

BUK9J0R9-40HLFPAK56mosfetsNexperiaPower S08
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Ayo is a software and hardware guy, a writer, and a prospective farmer. Ayo is passionate about STEM Education and Technology and has worked with over three EdTech startups in the last 5 years. Ayo currently talks and writes about technology especially in the areas of Internet of Things, Open Hardware, Startups, Precision Agriculture, Artificial Intelligence and Smart Cities. Ayo loves to cook and think about abstract ideas, and in his free time enjoys biking, hiking, traveling and playing video games. Reach me - charlesayibiowu@hotmail.com

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