Vishay Siliconix IRF9540

Overview

IRF9540 from Vishay Siliconix is a P-channel enhancement-mode power MOSFET in TO-220AB package, rated for -100 V V_DS, 0.20 Ω R_DS(on) at V_GS = -10 V, and -19 A continuous drain current at T_C = 25 °C. It delivers rugged repetitive avalanche capability (E_AS = 640 mJ), fast switching (t_d(on) = 16 ns), and operates up to +175 °C junction temperature - used in DC-DC converter high-side switches and motor control H-bridge legs.

For engineers reviewing the IRF9540 datasheet, IRF9540 pinout, IRF9540 application, or IRF9540 equivalent, this page provides verified device identity, validated thermal and dynamic parameters, confirmed TO-220AB pin mapping, and two rigorously cross-referenced alternative parts for industrial power switching design review.

Technical Context

The IRF9540 employs a third-generation silicon process optimized for low R_DS(on) and robust avalanche energy handling. Its gate threshold voltage range (-2.0 V to -4.0 V) ensures reliable turn-on with standard -10 V logic-level drive while maintaining noise immunity. The device integrates a body diode with t_rr = 130–260 ns and Q_rr = 0.35–0.70 μC, supporting synchronous rectification in flyback and buck converters.

Thermally, it features R_thJC = 1.0 °C/W and R_thJA = 62 °C/W, enabling 150 W dissipation at T_C = 25 °C. Its dV/dt rating of -5.5 V/ns and dynamic charge values (Q_g = 61 nC, Q_gd = 29 nC) support stable operation in hard-switched topologies without oscillation under typical gate resistance conditions.

Key Specifications

Pinout & Package

IRF9540 is housed in TO-220AB package with metal tab connected to drain (D), enabling direct heatsink mounting and minimizing thermal resistance (R_thJC = 1.0 °C/W). The plastic body isolates gate and source terminals from the heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRF9540, IRF9530 trades 0.10 Ω higher on-resistance for reduced gate charge, making it preferable in low-frequency linear regulators; STP9PF10 offers identical voltage rating in a footprint-compatible but vertically oriented TO-220FP package, easing mechanical integration where board height is limited.

Availability

IRF9540 is available at Aetrix Electronics and suitable for industrial motor drives, DC-DC converters, relay drivers, and overvoltage protection circuits requiring stable component supply and long-term manufacturability.

Supply support for IRF9540 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

Vishay Siliconix is a global leader in discrete semiconductors, specializing in high-reliability MOSFETs, diodes, and optoelectronics for industrial, automotive, and computing markets.

The IRF9540 belongs to Vishay's third-generation power MOSFET family engineered for ruggedness, low on-resistance, and fast switching in commercial-industrial power conversion and control systems.

FAQ

What is the maximum continuous drain current for IRF9540 at 100 °C case temperature?

The IRF9540 supports -13 A continuous drain current at T_C = 100 °C, per its absolute maximum ratings table. This derating reflects thermal limitations of the TO-220AB package and must be applied when ambient or heatsink conditions prevent maintaining T_C ≤ 25 °C. Designers should verify junction temperature using R_thJC = 1.0 °C/W and actual power dissipation to ensure T_J remains within -55 to +175 °C limits. The IRF9540 datasheet specifies this value explicitly in the "Continuous drain current" row under TC = 100 °C.

Is IRF9540 suitable for logic-level gate drive?

The IRF9540 is not a logic-level MOSFET; its gate threshold voltage range is -2.0 V to -4.0 V, and it requires -10 V for specified R_DS(on) = 0.20 Ω performance. While it may partially turn on with -5 V drive, conduction losses increase significantly due to higher on-resistance. For true logic-level operation, designers should select devices like the IRLML6344 or FDN306P instead. The IRF9540 datasheet confirms V_GS = -10 V as the test condition for all key static parameters.

Does IRF9540 have an integrated body diode, and what are its key parameters?

Yes, the IRF9540 includes an integral reverse p-n junction body diode with V_SD = -5.0 V at I_S = -19 A and T_J = 25 °C, reverse recovery time t_rr = 130–260 ns, and Q_rr = 0.35–0.70 μC. These values are measured under standardized conditions (I_F = -19 A, dI/dt = 100 A/μs) and directly impact freewheeling efficiency in half-bridge and synchronous rectifier topologies. The IRF9540 datasheet documents these in the "Drain-Source Body Diode Characteristics" section.

What is the thermal resistance from junction to case (R_thJC) for IRF9540?

The IRF9540 has a maximum junction-to-case thermal resistance (R_thJC) of 1.0 °C/W, as specified in the Thermal Resistance Ratings table of its datasheet. This value applies to the drain-connected metal tab and assumes proper mounting with thermal grease on a flat heatsink surface. It enables calculation of junction temperature rise (ΔT_J = P_D × R_thJC) for reliability analysis. The IRF9540's low R_thJC is a key enabler of its 150 W power dissipation rating at T_C = 25 °C.

Can IRF9540 replace IRF9540PbF-BE3 in a design?

Yes - IRF9540PbF-BE3 is the RoHS-compliant, halogen-free ordering variant of the IRF9540, with identical electrical, thermal, and mechanical specifications. The "PbF-BE3" suffix denotes lead-free terminations and green packaging; no performance or pinout differences exist between IRF9540 and IRF9540PbF-BE3. Designers may substitute either part without layout or validation changes, as confirmed in Vishay's Ordering Information table and Material Categorization documentation.