High-Speed N-Channel MOSFETs Tamp Down On-Resistance

The automotive sector is seeing a surge in the number of electronic components required, driven by demand for enhanced safety and convenience. At the same time, there’s a pressing need for improved power efficiency to optimize fuel and electricity consumption. In particular, for MOSFETs—essential ingredients in switching applications for automotive systems—there’s a growing requisite for lower on-resistance to minimize loss and heat generation.

To meet this need, ROHM introduced new MOSFETs compliant with the automotive reliability standard AEC-Q101 that are capable of high-speed switching with low on-resistance. 

N-Channel MOSFETs in Different Package Sizes

Adapting cutting-edge medium-voltage processes to meet the stringent reliability requirements of automotive products, ROHM developed 10 N-channel MOSFET models (N-channel MOSFETs conduct when a positive voltage is applied to the gate relative to the source). N-channel MOSFETs are more widely adopted in the market today due to their lower on-resistance (R_DS(on)) over P-channel variants, facilitating use in a broad range of circuits, again characterized by low R_DS(on).

The lineup, featuring 10 models across three package types (with plans to expand the lineup in the future) includes the RF9x120BKFRA, RQ3xxx0BxFRA, and RD3x0xxBKHRB versions. They’re well-suited for a variety of automotive applications, including motors for doors and seat positioning, as well as LED headlights, car infotainment/displays and advanced driver-assistance systems (ADAS).

With these MOSFETs, ROHM enhanced mounting reliability by utilizing wettable-flank technology for the DFN2020Y7LSAA package and gull-wing leads for the TO-252 package. Wettable-flank technology involves plating the sides of the leadframe on bottom electrode packages to improve mounting reliability.

Offered in voltage ratings of 40, 60, and 100 V, the new products incorporate a split-gate structure to achieve the low R_DS(on), contributing to higher efficiency operation in automotive applications. Split-gate structure is a technology that divides the gate of the MOSFET into multiple parts to efficiently regulate the flow of electrons. This is said to ensure fast, reliable operation. All models are qualified under the AEC-Q101 automotive reliability standard, guaranteeing high reliability.

Users can select from among three package types, depending on the application. For space-constrained sets such as ADAS, the compact DFN2020Y7LSAA (2.0 × 2.0 mm) and HSMT8AG (3.3 × 3.3 mm) packages are optimal choices. For automotive power applications, the widely used TO-252 (DPAK) package (6.6 × 10.0 mm) is also available. 

Going forward, ROHM plans to expand its lineup of medium-voltage N-channel MOSFETs to provide even greater miniaturization and higher efficiency in automotive applications. Mass production of the DFN3333 (3.3 × 3.3 mm) and HPLF5060 (5.0 × 6.0 mm) packages is scheduled for October 2024, followed by 80-V products in 2025. P-channel options are also scheduled for future release.