Infineon IRFI530NPBF N-Channel Power MOSFET: Key Specifications and Application Circuits

The Infineon IRFI530NPBF is a robust N-Channel power MOSFET designed for high-power switching applications. Leveraging advanced HEXFET technology, this component offers a compelling combination of high current handling, low on-state resistance, and fast switching speeds, making it a popular choice in power supply units, motor control systems, and audio amplifiers.

Key Specifications

The defining characteristics of the IRFI530NPBF are its high current capability and low gate drive requirements. Here are its critical specifications:

Drain-Source Voltage (V_DS): 100 V – Suitable for a wide range of medium-voltage applications.

Continuous Drain Current (I_D): 14 A at T_C = 25°C – Provides substantial current handling for power stages.

Pulsed Drain Current (I_DM): 56 A – Can handle high inrush currents.

On-State Resistance (R_DS(on)): 0.11 Ω (max) at V_GS = 10 V – This low on-resistance is crucial for minimizing conduction losses and improving efficiency, as it directly reduces power dissipation (I²R losses).

Gate Threshold Voltage (V_GS(th)): 2.0 V to 4.0 V – A standard threshold, making it compatible with most logic-level and standard drivers.

Total Gate Charge (Q_g): 36 nC (typ) – A key parameter for designing the gate drive circuit, as it determines the switching speed and drive current requirements.

Avalanche Energy Rated – Enhances robustness and reliability in inductive switching environments.

Application Circuits

The primary function of the IRFI530NPBF is to act as a high-speed switch. Two fundamental application circuits are detailed below.

1. Low-Side Switch Configuration

This is the most common circuit for controlling loads like DC motors, solenoids, or LEDs. The MOSFET is placed between the load and ground (GND).

Operation: When a sufficient voltage (typically 10V-12V) is applied to the gate via a driver IC or a simple logic circuit with a pull-down resistor, the MOSFET turns on, completing the circuit to ground and energizing the load. When the gate voltage is removed, the MOSFET turns off. A flyback diode is essential across an inductive load (like a motor coil) to provide a path for the inductive kickback current, protecting the MOSFET from voltage spikes that could exceed its V_DS rating.

2. Half-Bridge Inverter Stage (for SMPS or Motor Drives)

In switch-mode power supplies (SMPS) or DC-AC inverters for motor control, two MOSFETs (often one N-channel and one P-channel, or more commonly, two N-channels with a specialized high-side driver) are used in a half-bridge configuration. The IRFI530NPBF can serve as the low-side switch in such a pair.

Operation: The high-side and low-side switches are turned on and off complementarily. When the low-side MOSFET (IRFI530NPBF) is on, the output node is connected to ground. When it is off and the high-side switch is on, the output is connected to the bus voltage (e.g., 48V). This creates a pulsed output that can be filtered to generate a sine wave or used directly for power conversion. This setup requires a dedicated gate driver IC to correctly bias the high-side MOSFET's gate, which must be referenced to its source terminal that swings between ground and the bus voltage.

Design Considerations:

Gate Driving: While the gate can be driven with 10V, using a dedicated gate driver IC (e.g., IR2110) is highly recommended for fast switching. This minimizes switch transition times, reducing switching losses and preventing the MOSFET from operating in the high-dissipation linear region for too long.

Heat Sinking: Due to the power dissipated (P = I_D² R_DS(on) + Switching Losses), a suitable heat sink is often mandatory to keep the junction temperature within safe limits, ensuring long-term reliability.

ICGOODFIND Summary

The Infineon IRFI530NPBF is a highly versatile and robust power MOSFET. Its excellent specification balance, particularly its 100V voltage rating, 14A continuous current, and critically low 0.11Ω on-resistance, makes it an ideal component for designers seeking efficiency and reliability in medium-power switching applications such as power supplies, motor controllers, and audio amplifiers. Proper implementation, including sufficient gate driving and thermal management, is key to unlocking its full performance potential.

Keywords: Power MOSFET, Switching Applications, On-State Resistance, Gate Driver, Thermal Management