Infineon Technologies IRFS4321TRLPBF

Overview of IRFS4321TRLPBF N-channel MOSFET by Infineon Technologies

The IRFS4321TRLPBF, manufactured by Infineon Technologies, is part of the HEXFET series of power MOSFETs engineered for high-efficiency power conversion applications. Utilizing advanced Metal Oxide Semiconductor technology, this N-channel device features a maximum drain-to-source voltage rating of 150V and supports continuous drain currents up to 85A (at case temperature, Tc = 25°C), with a peak power dissipation of 350W. The IRFS4321TRLPBF is housed in a robust D2PAK surface-mount package (TO-263-3, TO-263AB), offering compactness and suitability for automated assembly processes. With its combination of low on-resistance and high current carrying capability, the IRFS4321TRLPBF is designed to address demanding engineering requirements for power control, switching efficiency, and system reliability.

Main electrical parameters of IRFS4321TRLPBF

Engineers evaluating the IRFS4321TRLPBF will find several notable electrical features beneficial for both design and procurement decisions. The device achieves a maximum Rds(on) value of 15mΩ at 33A with a gate drive of 10V, helping to minimize conduction losses and thermal buildup during operation. The gate threshold voltage (Vgs(th)) spans 3.0V to 5.0V, which ensures robust switching while simplifying gate drive design. The IRFS4321TRLPBF presents a total gate charge (Qg) of up to 110nC and an input capacitance (Ciss) of 4460pF (at Vds = 25V), supporting fast switching in high-frequency applications. With a gate-to-source voltage rating up to ±30V, this HEXFET MOSFET builds in flexibility for diverse drive topologies and enhanced system resilience.

Drain leakage current remains low (≤20μA at Vds = 150V), and the di/dt capability ensures reliability in pulse and transient conditions. Forward transconductance (gfs) reaches 130S at Vds = 25V and Id = 50A, supporting high-speed response for dynamic load demands.

IRFS4321TRLPBF thermal and physical properties

Power conversion engineers often scrutinize thermal performance closely. The IRFS4321TRLPBF features a junction-to-case thermal resistance (RthJC) as low as 0.43°C/W, enabling effective heat removal when paired with compatible PCB footprints and heat sink arrangements. Maximum junction temperature (Tj) is rated up to 175°C, providing design headroom for demanding ambient environments. The device’s rated continuous drain current falls to 60A at elevated case temperatures (Tc = 100°C). For mounting, the IRFS4321TRLPBF adopts surface-mount D2PAK, conforming to JEDEC TO-263AB standards; mechanical dimensions and lead assignments are calibrated for automated soldering and reflow processes, with a soldering temperature endurance of up to 300°C for 10 seconds.

IRFS4321TRLPBF switching behavior and dynamic characteristics

High-speed switching is central to the IRFS4321TRLPBF’s value proposition. Relevant timing specifications include turn-on delay of 18ns and rise time of 60ns, supporting fast transitions necessary for synchronous rectification and hard-switched converter stages. The turn-off delay is specified at 25ns; fall time reaches 35ns, enabling reduced dead time in bridge configurations. Gate charge splitting analysis reveals Qgs (gate-to-source) of 24nC and Qgd (Miller charge) of 21nC, facilitating tailored drive designs for EMI mitigation and optimized switching energy loss. Capacitance curves indicate strong voltage dependence, important for engineers modeling dynamic behavior in simulation environments.

IRFS4321TRLPBF diode features and recovery efficiency

Integral to the IRFS4321TRLPBF's topology is a built-in body diode, which provides essential reverse conduction paths in high-frequency power systems. The typical diode forward voltage registers at 1.3V (Is = 50A), with reverse recovery time ranging from 89ns (typical) to 130ns (max). The device supports continuous source current up to 85A and pulsed capability up to 330A, making it suitable for aggressive transient conditions. Reverse recovery charge is specified at 300nC (typical), supporting reduced switching losses and improved efficiency in full-bridge and synchronous rectification topologies. Device designers should consider these diode parameters when analyzing system-level switching losses and EMI profiles.

Typical uses of IRFS4321TRLPBF HEXFET MOSFET

The IRFS4321TRLPBF is engineered for applications requiring both efficiency and robust performance. Typical use cases include motion control drives, high-efficiency synchronous rectification within switched-mode power supplies (SMPS), and uninterruptible power supply (UPS) platforms. Its ability to withstand high current pulses and its fully characterized Avalanche Safe Operating Area (SOA) support suitability for hard-switched circuits and challenging high-frequency environments. The device’s improved diode recovery and low gate charge jointly support designs where fast turn-on/off dynamics and low switching losses are essential, such as DC-DC converters, motor controllers, and power factor correction (PFC) circuits.

IRFS4321TRLPBF standards compliance and environmental condition

From a procurement perspective, compliance plays a central role in supply chain integrity. The IRFS4321TRLPBF is RoHS3 compliant and classified with Moisture Sensitivity Level (MSL) 1, offering unlimited storage life under recommended conditions. REACH status is unaffected, ensuring suitability for global deployments with stringent chemical controls. Export classification is EAR99, with harmonized tariff code (HTSUS): 8541.29.0095. These statuses enable smooth qualification into international production flows and simplify BOM-level compliance audits.

Alternative or compatible models for IRFS4321TRLPBF

For engineers and buyers seeking cross-references for the IRFS4321TRLPBF, equivalent models within the same HEXFET MOSFET family can be considered, such as IRFS4321PbF and IRFSL4321PbF (note differences in lead plating or package features). International Rectifier, now part of Infineon Technologies, supplies these alternatives with comparable electrical and mechanical profiles, ensuring BOM flexibility and supply assurance. When substituting or qualifying replacement products, engineers must validate critical parameters including Rds(on), voltage rating, current rating, gate charge, and package compatibility to safeguard interchangeability and performance in the intended application.

Conclusion

The Infineon Technologies IRFS4321TRLPBF N-channel 150V HEXFET MOSFET presents a compelling solution for demanding power control applications. With its blend of high current capability, low on-resistance, robust avalanche and diode characteristics, and compliance with global environmental standards, it addresses the challenging needs of modern engineering and procurement teams. The D2PAK surface-mount form factor supports streamlined manufacturing, and its dynamic performance metrics offer clear advantages for efficiency-critical systems. As part of a well-established product family, the IRFS4321TRLPBF enables flexible system integration, cross-referencing, and long-term reliability, making it a reference choice in the evaluation and selection of high-performance MOSFETs for power electronics.