Infineon BSC042N03MSG 30V N-Channel MOSFET: Datasheet, Application Circuit, and Typical Characteristics

The Infineon BSC042N03MSG is a state-of-the-art N-Channel MOSFET engineered using Infineon’s advanced OptiMOS™ technology. Designed for a maximum drain-source voltage (V_DS) of 30V, this power MOSFET is optimized for high-efficiency, high-frequency switching applications in a compact package. Its primary use cases include load switching, DC-DC conversion, and motor control in consumer electronics, computing, and low-voltage power systems.

A key highlight of the BSC042N03MSG is its exceptionally low on-state resistance (R_DS(on)) of just 1.7 mΩ at 10 V gate drive. This ultra-low resistance minimizes conduction losses, leading to higher system efficiency and reduced heat generation. Combined with a continuous drain current (I_D) rating of 100 A, it is capable of handling high current levels in a small footprint, the SuperSO8 package, which offers superior thermal performance and power density.

Typical Characteristics

The device exhibits excellent switching performance due to its low gate charge (Q_G) and low figure-of-merit (FOM = R_DS(on) × Q_G). This makes it highly suitable for high-frequency switching power supplies where fast turn-on and turn-off are critical. The transfer characteristics show a low threshold voltage (V_GS(th)), typically around 1.8 V, ensuring compatibility with low-voltage logic-level drive signals from modern microcontrollers and PWM controllers.

Application Circuit: Synchronous Buck Converter

A common application for the BSC042N03MSG is as the low-side switch in a synchronous buck converter circuit. In this setup:

The high-side switch (often another similar MOSFET) is turned on to charge the inductor.

The BSC042N03MSG is then switched on to provide a low-resistance path to ground, allowing the inductor current to freewheel with minimal voltage drop and power loss.

Its fast body diode characteristics and low R_DS(on) are crucial for minimizing dead time and improving the overall efficiency of the converter. Proper gate driving is essential; a dedicated MOSFET gate driver IC is recommended to provide the necessary peak current for fast switching and to avoid operating in the linear region.

Thermal Management

Despite its high efficiency, effective thermal management is vital for reliable operation under high load currents. The SuperSO8 package is designed to be mounted on a PCB pad that acts as a heatsink. Ensuring a sufficient copper area connected to the drain pins (which are also the thermal pads) is critical for dissipating heat into the board and maintaining a low junction temperature.

Datasheet Overview

The datasheet provides all necessary information for design-in, including:

Absolute Maximum Ratings: The limits for voltage, current, and temperature.

Electrical Characteristics: Detailed tables for R_DS(on), V_GS(th), capacitance values, and switching times.

Typical Performance Characteristics: Graphs showing the relationship between R_DS(on) and gate voltage, switching behavior, and body diode characteristics.

Package Outline and Recommended PCB Layout: Essential for optimizing thermal and electrical performance.

ICGOODFIND: The Infineon BSC042N03MSG stands out as an elite component for power designers seeking to maximize efficiency and power density in space-constrained, high-current applications. Its blend of ultra-low R_DS(on), high current capability, and superior switching performance makes it an outstanding choice for next-generation power systems.

Keywords: OptiMOS™, Low R_DS(on), Synchronous Buck Converter, SuperSO8, High Current Switching.