Infineon Technologies AUIRLZ44Z

Overview

AUIRLZ44Z from Infineon Technologies (formerly International Rectifier) is an automotive-grade N-channel HEXFET® Power MOSFET in TO-220AB package, rated for 55 V V_BRDSS, 11 mΩ typical R_DS(on) at V_GS = 10 V, and 51 A continuous drain current at T_C = 25°C. It operates up to 175°C junction temperature and supports repetitive avalanche, making it suitable for high-reliability engine control, powertrain DC-DC converters, and load switching in 12 V/24 V automotive systems.

For engineers reviewing the AUIRLZ44Z datasheet, AUIRLZ44Z pinout, AUIRLZ44Z application, or AUIRLZ44Z equivalent, key selection criteria include its ultra-low on-resistance, AEC-Q101 qualification, fast switching (t_r = 160 ns, t_f = 42 ns), body diode recovery (t_rr = 21–32 ns), and thermal robustness under pulsed inductive loads.

Technical Context

This MOSFET employs advanced planar silicon processing to achieve low R_DS(on) per die area while maintaining ruggedness against unclamped inductive switching. Its gate charge profile (Q_g = 24–36 nC, Q_gd = 12 nC) enables efficient gate drive with standard 7.5 Ω resistor-based drivers in high-frequency PWM applications.

The device integrates a robust intrinsic body diode with V_SD ≤ 1.3 V at I_S = 31 A and Q_rr = 16–24 nC, supporting synchronous rectification and freewheeling in buck converters and motor H-bridges. Avalanche energy rating (E_AS = 51 mJ, E_AR = 78 mJ) is validated per AEC-Q101 test conditions using L = 0.166 mH, R_G = 25 Ω, and I_AS = 31 A.

Key Specifications

Pinout & Package

Package: TO-220AB - Through-hole, single-ended heat sink mountable package with isolated tab (drain-connected). Thermal resistance R_θJC = 1.87 °C/W enables >40 W dissipation with modest heatsinking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STL220N4F7AG and NTMFS5C670NL, the AUIRLZ44Z uniquely combines 55 V rating, AEC-Q101 qualification, and proven repetitive avalanche performance-making it the only option among the three validated for under-hood solenoid and motor control where transient immunity and thermal resilience are non-negotiable.

Availability

AUIRLZ44Z is available at Aetrix Electronics and suitable for engine control units, electric power steering inverters, and body control module load switching requiring stable component supply across automotive production lifecycles.

Supply support for AUIRLZ44Z 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

Infineon Technologies is a global semiconductor leader specializing in power management, automotive electronics, and industrial control solutions, with core expertise in silicon and wide-bandgap power devices.

The AUIRLZ44Z belongs to Infineon's automotive-qualified HEXFET® MOSFET product line, engineered specifically for high-current, high-temperature switching in engine, transmission, and chassis control systems where reliability under transient stress is mandatory.

FAQ

Is the AUIRLZ44Z pin-compatible with the non-automotive IRFZ44Z?

No. While both share TO-220AB packaging and identical pinout (Drain–Source–Gate), the AUIRLZ44Z incorporates process and screening enhancements for AEC-Q101 compliance-including tighter R_DS(on) distribution, extended temperature characterization, and validated repetitive avalanche performance not guaranteed in the IRFZ44Z. Substitution requires requalification.

What is the maximum allowable gate drive voltage for reliable operation?

The absolute maximum V_GS is ±16 V per datasheet. For robust long-term reliability in automotive applications, gate drive should be limited to 10–12 V. Exceeding 12 V increases gate oxide stress and accelerates wear-out under thermal cycling; 10 V ensures full enhancement while preserving margin against transients.

Can the AUIRLZ44Z be used in synchronous rectification topologies?

Yes, but with design constraints. Its body diode has t_rr = 21–32 ns and Q_rr = 16–24 nC, enabling use in low-to-moderate frequency (<100 kHz) synchronous buck converters. However, its R_DS(on) is higher than dedicated sync-FETs, so efficiency gains over Schottky diodes diminish above 5 A load current.

Does the TO-220AB package require electrical isolation when mounted to a heatsink?

Yes. The metal tab is internally connected to the Drain terminal. If the heatsink is grounded or referenced to a different potential than the drain node, an electrically isolating pad (e.g., mica or polymer film) plus shoulder washer must be used. Failure to isolate risks short circuits, ground loops, or latch-up in high-side configurations.