Infineon IRFS4115TRL7PP Power MOSFET: Key Specifications and Application Circuit Design
The Infineon IRFS4115TRL7PP is a high-performance N-channel power MOSFET designed to meet the rigorous demands of modern power conversion systems. Leveraging Infineon's advanced HEXFET® technology, this component is optimized for low on-state resistance and high switching speed, making it an ideal choice for a wide array of applications, from switch-mode power supplies (SMPS) to motor control and DC-DC converters.
Key Electrical Specifications
The standout feature of the IRFS4115TRL7PP is its exceptionally low drain-to-source on-state resistance (RDS(on)). At a gate-to-source voltage (VGS) of 10 V, the RDS(on) is a mere 3.7 mΩ maximum. This low resistance is crucial for minimizing conduction losses, which directly translates to higher efficiency and reduced heat generation, allowing for more compact thermal management solutions.
The device is rated for a maximum drain-to-source voltage (VDS) of 150 V and a continuous drain current (ID) of 104 A at a case temperature (TC) of 100°C. This robust voltage and current handling capability make it suitable for intermediate bus voltages commonly found in 48V input systems, telecom infrastructure, and industrial power supplies.
Furthermore, its low gate charge (QG typical 110 nC) and fast switching characteristics ensure that switching losses are kept to a minimum. This is particularly vital in high-frequency switching circuits where efficiency is paramount.
Application Circuit Design: A Synchronous Buck Converter Example
A primary application for the IRFS4115TRL7PP is in the synchronous buck converter topology, which is ubiquitous in point-of-load (POL) voltage regulation. Here’s a breakdown of a typical circuit design:
1. Component Selection:
Control IC: A dedicated PWM controller with independent high-side and low-side gate drive outputs is required.
High-Side MOSFET (Q1): The IRFS4115TRL7PP is used here for its low RDS(on) and fast switching.
Low-Side MOSFET (Q2): An identical MOSFET is often used for the synchronous rectifier to simplify design and procurement.
Inductor (L1): Selected based on the desired output voltage ripple, switching frequency (e.g., 300 kHz), and maximum load current.
Input/Output Capacitors (CIN, COUT): Low-ESR ceramic and electrolytic capacitors are used to filter the input noise and smooth the output voltage.
2. Gate Driving Considerations:
Driving this MOSFET effectively is critical. The total gate charge necessitates a gate driver IC capable of sourcing and sinking peak currents of several amperes. A driver like the IR2110 is a common choice. A small series resistor (e.g., 2.2-10 Ω) is placed in series with the gate to dampen ringing and control the switching speed, mitigating EMI issues.
3. Layout Imperatives:
Minimizing Parasitic Inductance: The power loop (CIN → Q1 → L1 → COUT → CIN) and the switch node (connection between Q1, Q2, and L1) must be as physically small as possible with wide copper pours to minimize parasitic inductance. This prevents voltage spikes and ensures stable operation.
Thermal Management: Given the high current capability, a properly sized PCB heatsink connected to the drain tab is essential. Using multiple vias under the package to connect to a large ground plane on an inner layer is an effective method to dissipate heat.
By carefully considering these specifications and design principles, engineers can harness the full potential of the IRFS4115TRL7PP to build highly efficient and reliable power electronic systems.
ICGOODFIND: The Infineon IRFS4115TRL7PP stands out as a superior component for power management, offering an outstanding balance of very low RDS(on), high current capability, and robust switching performance, which is essential for achieving high efficiency in demanding power conversion applications.
Keywords:
Power MOSFET
Low RDS(on)
Synchronous Buck Converter
Switching Losses
Gate Driver
