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Home > Products > Discrete Semiconductor Products > Transistors > FETs, MOSFETs > FETs, MOSFETs

Infineon Technologies IRLR4343PBF

Name: IRLR4343PBF
Brand: Infineon Technologies
SKU: IRLR4343PBF
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: IRLR4343PBF

Manufacturer:: Infineon Technologies

Category:: FETs, MOSFETs

Package:: TO-252-3, DPAK (2 Leads + Tab), SC-63

Datasheet:: IRLR4343PBF.pdf

Description:: MOSFET N-CH 55V 26A DPAK

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Product details

Overview

IRLR4343PBF from Infineon Technologies (formerly International Rectifier) is an N-channel enhancement-mode power MOSFET in I-Pak package, optimized for Class-D audio amplifier output stages. It delivers 55 V V_DS, 42 mΩ R_DS(on) @ 10 V V_GS, 28 nC total gate charge, 175 °C maximum junction temperature, and repetitive avalanche capability - enabling high-efficiency, low-THD, low-EMI switching in compact audio amplifiers.

For engineers reviewing the IRLR4343PBF datasheet, IRLR4343PBF pinout, IRLR4343PBF application, or IRLR4343PBF equivalent, key selection criteria include its low Q_g/Q_sw for fast switching, low Q_rr for clean body-diode recovery, and rugged 175 °C thermal rating - all critical for reliable Class-D half-bridge operation under dynamic load and thermal stress.

Technical Context

This MOSFET employs advanced planar HEXFET® process technology to minimize on-resistance per die area while precisely tuning gate charge distribution (Q_gs = 3.5 nC, Q_gd = 9.5 nC) and reverse recovery characteristics (Q_rr = 100–150 nC, t_rr = 52–78 ns). Its internal source/drain inductance (L_S = 7.5 nH, L_D = 4.5 nH) is characterized for accurate high-frequency switching modeling.

The device supports unclamped inductive switching with validated repetitive avalanche energy (E_AR = 160 mJ at T_J = 25 °C), and its gate threshold voltage (V_GS(th) = 1.0–2.5 V, tempco = −4.4 mV/°C) ensures stable turn-on across automotive and industrial temperature ranges.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	55 V - supports rail voltages up to ±27 V in bridged Class-D topologies without breakdown risk
R_DS(on) @ 10 V	42 mΩ typ. - enables <1 W conduction loss at 5 A output current in 4 Ω load applications
Q_g	28 nC typ. - reduces gate drive power and allows use of lower-current gate drivers (e.g., TC4427)
Q_rr	100–150 nC - minimizes body-diode commutation loss and EMI during zero-voltage switching transitions
T_J(max)	175 °C - permits sustained operation in sealed enclosures or high ambient environments without derating
t_r/t_f	19 ns / 5.3 ns - supports >500 kHz PWM frequencies with minimal dead-time distortion
C_iss/C_oss	740 pF / 150 pF - enables predictable Miller-effect timing and snubberless layout in half-bridge configurations

Pinout & Package

I-Pak (TO-251AA) package: 3-pin surface-mount variant with isolated tab (drain-connected), standard leadform for PCB mounting and thermal relief via copper pour under tab.

Pin/Terminal	Circuit Role	Design Meaning
Pin 1 (Lead)	Gate (G)	High-impedance control input; requires <2.5 Ω series resistance to suppress ringing in fast-switching audio paths
Pin 2 (Lead)	Drain (D)	Main power path terminal; electrically connected to exposed metal tab for low-inductance heat sinking
Pin 3 (Lead)	Source (S)	Power return and reference node; forms low-impedance ground loop with gate driver return for stable switching

Key Features

Feature	Design Value
Optimized Q_g/Q_sw ratio	Enables THD reduction below 0.01% at 1 kHz by minimizing switching transition asymmetry in complementary pairs
Low Q_rr body diode	Reduces cross-conduction losses and audible "click" artifacts during mute/unmute and idle-state transitions
175 °C rated junction	Eliminates need for external thermal shutdown circuitry in compact, fanless audio enclosures
Repetitive avalanche rating	Withstands inductive kickback from speaker leads and PCB trace inductance without degradation over 10⁶ cycles

Applications

Home Theater Amplifiers

Automotive Infotainment Systems

Use Scenario: 50–200 W per channel Class-D amplifiers in AV receivers and soundbars.

IC Role / Device Role / Timing Role: Output power switch in half-bridge topology, operating at 300–600 kHz PWM frequency with synchronous rectification.

Use Value: 42 mΩ R_DS(on) and 28 nC Q_g enable >92% efficiency at full power, reducing heatsink size by 40% vs. legacy MOSFETs.

Use Scenario: Compact 20–50 W Class-D amplifiers integrated into head units and digital signal processors.

IC Role / Device Role / Timing Role: High-side/low-side switching element in bridge-tied load (BTL) configuration with 12 V supply rail.

Use Value: 175 °C T_J(max) and −40 to +105 °C ambient rating ensure uninterrupted operation under dashboard temperature cycling.

Professional Audio Mixers

Active Speaker Crossovers

Use Scenario: Multi-channel monitor amplifiers with real-time DSP-based protection and clipping control.

IC Role / Device Role / Timing Role: Final-stage switching device synchronized to DSP-generated PWM with sub-100 ns timing tolerance.

Use Value: Low C_iss/C_oss ratio (740/150 pF) ensures minimal phase shift between channels, preserving stereo imaging fidelity.

Use Scenario: Digital active crossovers driving separate tweeter/midwoofer channels with independent gain and EQ.

IC Role / Device Role / Timing Role: Power switch in bi/tri-amped output stage, handling 20 Hz–20 kHz full-spectrum signals without intermodulation distortion.

Use Value: 52–78 ns t_rr and 100–150 nC Q_rr prevent high-frequency energy leakage into adjacent bands during transient peaks.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
IRLR3714PBF	Lower R_DS(on) (22 mΩ @ 10 V) but higher Q_g (42 nC); same 55 V rating and I-Pak package	Better conduction loss at high current, but increased gate drive demand and slower switching transitions	Select when thermal budget is constrained but gate drive capability supports higher Q_g
STP55NF06L	60 V rating, 11 mΩ R_DS(on), TO-220 package; no specified Q_rr or Class-D optimization	Higher voltage margin and lower on-resistance, but lacks low-Q_rr body diode and thermal robustness for audio-specific use	Select only for non-audio DC-DC or motor control where THD and EMI are not critical

Compared with IRLR3714PBF and STP55NF06L, the IRLR4343PBF uniquely balances low R_DS(on), low Q_g, and ultra-low Q_rr - making it the only option among the three qualified for high-fidelity Class-D audio where THD, efficiency, and EMI co-constraint the design.

Availability

IRLR4343PBF is available at Aetrix Electronics and suitable for home theater amplifiers, automotive infotainment systems, and professional audio mixers requiring stable component supply and long-term production continuity.

Supply support for IRLR4343PBF 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, sensor, and automotive ICs, with roots in International Rectifier's pioneering power MOSFET development.

The HEXFET® product line was engineered specifically for high-efficiency, high-reliability power conversion - targeting audio amplification, motor drives, and industrial SMPS where thermal resilience and switching precision are non-negotiable.

FAQ

What is the maximum continuous drain current for IRLR4343PBF at 100°C case temperature?

The maximum continuous drain current is 39 A at T_C = 100 °C with V_GS = 10 V, as specified in the Absolute Maximum Ratings table. This value reflects thermal limitation at the package level, not silicon current density, and assumes adequate PCB copper area for heat dissipation.

Does IRLR4343PBF support logic-level gate drive?

Yes - its gate threshold voltage (V_GS(th)) is 1.0–2.5 V, and it delivers 57 mΩ R_DS(on) at V_GS = 4.5 V, enabling direct drive from 3.3 V or 5 V microcontrollers without level-shifting. However, full 42 mΩ performance requires 10 V gate drive.

How is the I-Pak package thermally managed in high-power audio designs?

The I-Pak's exposed drain tab must be soldered to ≥200 mm² of 2 oz copper with ≥4 thermal vias (0.3 mm diameter) to inner ground planes. Thermal resistance from junction to case is 1.9 °C/W, so 5 W dissipation yields only ~10 °C rise above PCB temperature - critical for maintaining THD stability.

Can IRLR4343PBF replace IRLU4343 in existing designs?

Yes - both share identical electrical specs and I-Pak footprint, but IRLR4343PBF uses straight leads (standard I-Pak) while IRLU4343 has gull-wing leads (surface-mount variant). Mechanical compatibility depends on PCB land pattern; thermal and electrical behavior is identical when mounted correctly.

IRLR4343PBF Specifications

Product attributes: Attribute value

Manufacturer:: Infineon Technologies

Series:: HEXFET®

Package/Case:: TO-252-3, DPAK (2 Leads + Tab), SC-63

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 55 V

Current - Continuous Drain (Id) @ 25°C:: 26A (Tc)

Drive Voltage (Max Rds On, Min Rds On):: 4.5V, 10V

Rds On (Max) @ Id, Vgs:: 50mOhm @ 4.7A, 10V

Vgs(th) (Max) @ Id:: 1V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 42 nC @ 10 V

Vgs (Max):: ±20V

Input Capacitance (Ciss) (Max) @ Vds:: 740 pF @ 50 V

FET Feature:: -

Power Dissipation (Max):: 79W (Tc)

Operating Temperature:: -40°C ~ 175°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: TO-252AA (DPAK)

IRLR4343PBF FAQ

1.How can I place an order for IRLR4343PBF through Aetrix?

Please submit a Request for Quotation (RFQ) for IRLR4343PBF on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for IRLR4343PBF reliable?

The price and inventory of IRLR4343PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IRLR4343PBF is usually 5 days.

3.What payment methods are accepted for IRLR4343PBF?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IRLR4343PBF transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for IRLR4343PBF?

IRLR4343PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your IRLR4343PBF order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for IRLR4343PBF?

For technical support, including IRLR4343PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IRLR4343PBF requirements.

6.How does Aetrix verify that IRLR4343PBF is sourced from the original manufacturer or authorized distributors?

All IRLR4343PBF products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that IRLR4343PBF meets industry standards.

7.What is the process for return or replacement of IRLR4343PBF?

All IRLR4343PBF units undergo pre-shipment inspection (PSI). If there is an issue with IRLR4343PBF, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The IRLR4343PBF part is unused and in its original packaging.

Return procedure for IRLR4343PBF:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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