Infineon BSS123NH6433XTMA1: A High-Performance N-Channel Enhancement Mode MOSFET

The Infineon BSS123NH6433XTMA1 is a state-of-the-art N-Channel enhancement mode field-effect transistor (MOSFET) housed in a compact, surface-mount SC-75 (TSOP-6) package. This device is engineered to deliver exceptional efficiency and reliability in low-voltage, low-power applications, making it a cornerstone component in modern electronic design.

Key Electrical Characteristics and Features

A deep dive into its datasheet reveals a component optimized for switching. With a drain-source voltage (V_DS) of 100 V and a continuous drain current (I_D) of 170 mA, it is perfectly suited for a wide range of low-power control tasks. One of its most significant advantages is its very low threshold voltage (V_GS(th)), typically around 1.5 V, which allows it to be driven directly from 3.3 V or 5 V microcontroller GPIO pins without the need for additional driver circuitry.

Furthermore, the BSS123NH6433XTMA1 boasts an ultra-low on-resistance (R_DS(on)) of just 6.5 Ω max. at V_GS = 10 V. This low resistance minimizes conduction losses, leading to higher efficiency and reduced heat generation during operation. The small package size offers a minimal footprint on the PCB, which is critical for space-constrained applications like portable and wearable devices.

Primary Applications and Circuit Implementation

According to its application notes, this MOSFET excels as a high-speed switching device. Its primary use cases include:

Load Switching: Efficiently powering subsystems on and off in battery-operated devices to conserve energy.

Signal Level Shifting: Interfacing between circuits operating at different voltage levels.

DC-DC Converters: Serving as the main switching element in low-power converter topologies (e.g., buck, boost converters).

Driver for LEDs, Relays, or Small Motors: Providing solid-state control for various output devices.

A typical application circuit for a microcontroller interface is straightforward. The load (e.g., an LED) is connected in series with the power supply and the MOSFET's drain pin. The source pin is connected to ground. The microcontroller's output pin is connected directly to the gate pin, often with a small series resistor (e.g., 100 Ω) to dampen any ringing. A pull-down resistor (e.g., 10 kΩ) from the gate to ground ensures the MOSFET remains off when the microcontroller pin is in a high-impedance state, preventing accidental activation.

Thermal and Layout Considerations

For optimal performance and longevity, proper PCB layout is essential. Designers should:

Minimize parasitic inductance in the high-current drain-source loop.

Use a sufficiently large ground plane to aid heat dissipation.

Ensure the thermal pad (if applicable) is properly soldered to a copper area on the PCB to act as a heatsink, preventing thermal runaway during continuous operation.

Conclusion and Summary by ICGOODFIND

ICGOODFIND: The Infineon BSS123NH6433XTMA1 is a highly efficient and compact MOSFET solution, ideal for modern low-power design. Its low threshold voltage and low on-resistance make it exceptionally easy to use and effective, reducing both system complexity and power consumption. For designers seeking a reliable switch for microcontroller-driven applications, this component represents an excellent choice, balancing performance, size, and cost.

Keywords:

1. N-Channel MOSFET

2. Enhancement Mode

3. Low Threshold Voltage

4. SC-75 Package

5. Load Switching