NXP Semiconductors IRFZ44N,127

Overview

IRFZ44N,127 from NXP Semiconductors (formerly Philips) is an N-channel enhancement-mode TrenchMOS™ power transistor in TO-220AB package, featuring 55 V V_DS, 49 A I_D (DC), 22 mΩ R_DS(ON) at V_GS = 10 V, 110 W P_tot, and integral ESD protection up to 2 kV. It is engineered for high-efficiency switching in DC-DC converters, motor drives, and SMPS primary-side switch applications.

For engineers reviewing the IRFZ44N,127 datasheet, IRFZ44N,127 pinout, IRFZ44N,127 application, or IRFZ44N,127 equivalent, key selection criteria include its low on-resistance at 10 V gate drive, robust avalanche energy rating (110 mJ), thermal resistance junction-to-mounting-base (1.4 K/W), and validated operation up to 175 °C junction temperature.

Technical Context

The IRFZ44N,127 employs trench-gate MOSFET technology to achieve reduced R_DS(ON) and improved switching performance versus planar MOSFETs. Its gate threshold voltage (2.0–4.0 V at 25 °C) enables reliable turn-on with standard logic-level drivers, while its 155–215 pF Crss supports predictable Miller-effect control during hard-switching.

It integrates a fast-recovery body diode (t_rr = 47 ns, Q_rr = 0.15 µC) with V_SD = 0.95–1.2 V at 25 A, making it suitable for synchronous rectification and freewheeling paths where reverse recovery losses must be minimized.

Key Specifications

Pinout & Package

Package: TO-220AB (SOT78), plastic envelope with metal tab electrically connected to drain; net mass 2 g; UL94 V0-compliant epoxy.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel power MOSFET applications.

Compared with STP48NF10 and IRFZ44NPBF, the IRFZ44N,127 offers optimal balance of low gate charge (62 nC), proven thermal performance (1.4 K/W), and cost-effective legacy availability-making it ideal for high-volume 48 V industrial switching where lead-free conversion is not mandated.

Availability

IRFZ44N,127 is available at Aetrix Electronics and suitable for switched-mode power supplies, motor control circuits, and DC-DC conversion applications requiring stable component supply across extended production lifecycles.

Supply support for IRFZ44N,127 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader delivering high-performance analog, logic, and power solutions for automotive, industrial, and consumer markets.

The IRFZ44N,127 belongs to NXP's legacy TrenchMOS™ power transistor family, designed specifically for high-current, medium-voltage switching applications demanding low R_DS(ON), rugged avalanche capability, and industrial-grade reliability.

FAQ

What is the maximum continuous drain current for IRFZ44N,127 at 100 °C mounting base temperature?

The IRFZ44N,127 supports 35 A continuous drain current (I_D) at T_mb = 100 °C, as specified in the Limiting Values table. This derating reflects thermal constraints of the TO-220AB package and must be applied in thermally constrained enclosures or high-ambient environments. The IRFZ44N,127 maintains safe operation up to 175 °C junction temperature, provided heatsinking keeps T_j within limit.

Does IRFZ44N,127 have built-in ESD protection, and what is its rating?

Yes, the IRFZ44N,127 includes integral Zener diodes providing electrostatic discharge protection rated at 2 kV per Human Body Model (100 pF, 1.5 kΩ). This protection is inherent to the device structure and does not require external components. The IRFZ44N,127 remains susceptible to damage if exposed to repeated ESD events beyond specification, so standard ESD handling precautions must still be observed during assembly.

Can IRFZ44N,127 be driven directly by a 3.3 V microcontroller GPIO pin?

No, the IRFZ44N,127 cannot be fully enhanced with 3.3 V gate drive. Its gate threshold voltage ranges from 2.0–4.0 V, and R_DS(ON) is only guaranteed at V_GS = 10 V. At 3.3 V, the device operates in weak inversion with high R_DS(ON) (>1 Ω), causing excessive heating. A dedicated gate driver or level-shifting circuit is required to deliver ≥10 V to the IRFZ44N,127 gate for efficient switching.

What is the thermal resistance junction-to-ambient for IRFZ44N,127 in free air?

The IRFZ44N,127 has a maximum thermal resistance junction-to-ambient (R_{th j-a}) of 60 K/W when mounted in free air with no heatsink. This value assumes standard TO-220AB mounting conditions and defines worst-case self-heating. For reliable operation above ~5 W dissipation, the IRFZ44N,127 must be mounted to a heatsink; its junction-to-mounting-base resistance is 1.4 K/W, enabling precise thermal modeling when heatsink parameters are known.

Is the body diode of IRFZ44N,127 suitable for synchronous rectification?

The IRFZ44N,127 body diode has t_rr = 47 ns and Q_rr = 0.15 µC, which is faster than many discrete diodes but slower than purpose-built synchronous rectifiers. While usable in low-frequency (<100 kHz) synchronous buck topologies, its reverse recovery characteristics may cause shoot-through or increased loss at higher frequencies. For optimal efficiency, the IRFZ44N,127 is best deployed as a controlled switch, not as a primary rectifier; dedicated SR controllers remain preferred for high-frequency sync rectification.