Vishay Siliconix IRFZ20

Overview

IRFZ20 from Vishay Siliconix is a 200 V, 5.2 A N-channel power MOSFET in TO-220AB package, optimized for logic-level gate drive (V_GS(th) = 1.0–2.0 V), low R_DS(on) of 0.80 Ω at V_GS = 5 V, and fast switching with 4.2 ns turn-on delay. It serves as a robust high-voltage switch in DC-DC converters, motor control stages, and industrial power supplies.

For engineers reviewing the IRFZ20 datasheet, IRFZ20 pinout, IRFZ20 application, or IRFZ20 equivalent, key selection criteria include its repetitive avalanche rating (E_AS = 125 mJ), dV/dt immunity (5.0 V/ns), and thermal resistance (R_thJC = 2.5 °C/W), critical for reliable operation in unclamped inductive switching and thermally constrained designs.

Technical Context

The IRFZ20 employs a third-generation planar vertical DMOS structure enabling stable R_DS(on) over temperature and ruggedized avalanche performance. Its gate threshold voltage range (1.0–2.0 V) ensures compatibility with 3.3 V and 5 V microcontroller outputs without level-shifting circuitry.

Dynamic parameters-including Q_g = 16 nC, Q_gd = 9.6 nC, and C_iss = 360 pF-support efficient high-frequency switching up to several hundred kHz while maintaining low gate drive loss. The integrated body diode exhibits t_rr = 180–270 ns and Q_rr = 1.1–1.7 μC, suitable for synchronous rectification and freewheeling in hard-switched topologies.

Key Specifications

Pinout & Package

IRFZ20 is housed in a TO-220AB package with standard three-terminal layout: Drain (D) connected to tab, Source (S) and Gate (G) on leads. The metal tab is electrically connected to the Drain, requiring isolation when mounted to heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRFZ20, IRFZ34N offers superior conduction efficiency at low voltage but sacrifices logic-level drive; STP20NM20 matches voltage rating and gate compatibility but trades off switching speed and gate drive efficiency-making IRFZ20 optimal for 200 V, medium-frequency, logic-driven power switching.

Availability

IRFZ20 is available at Aetrix Electronics and suitable for industrial motor drives, DC-DC power conversion, and uninterruptible power supply (UPS) inverters requiring stable component supply across multi-year production cycles.

Supply support for IRFZ20 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 power MOSFETs, diodes, and optoelectronics with emphasis on ruggedness, reliability, and application-specific optimization.

The IRFZ20 belongs to Vishay's legacy power MOSFET family designed for industrial and commercial switching applications demanding high voltage tolerance, logic-level compatibility, and proven avalanche robustness.

FAQ

What is the maximum continuous drain current for IRFZ20 at 100 °C case temperature?

The IRFZ20 supports 3.3 A continuous drain current at T_C = 100 °C, as specified in its Absolute Maximum Ratings table. This derating reflects thermal limitations of the TO-220AB package and ensures safe operation within the 150 °C maximum junction temperature limit. Designers must verify heatsink sizing to maintain T_C ≤ 100 °C under full-load conditions for sustained reliability of the IRFZ20.

Does IRFZ20 have an integrated body diode, and what are its key parameters?

Yes, the IRFZ20 includes an integral reverse p-n junction body diode rated for 5.2 A continuous source-drain current and 21 A pulsed current. Its forward voltage is 1.8 V at 5.2 A and 25 °C, with reverse recovery time t_rr = 180–270 ns and Q_rr = 1.1–1.7 μC. These values are measured under standardized conditions (I_F = 5.2 A, dI/dt = 100 A/μs) and define freewheeling behavior in inductive switching circuits using the IRFZ20.

Is IRFZ20 suitable for use with 3.3 V microcontroller GPIOs without a gate driver?

Yes, the IRFZ20 is explicitly designed for logic-level gate drive, with V_GS(th) ranging from 1.0 V to 2.0 V and full enhancement achieved at V_GS = 4.0 V. A 3.3 V GPIO can reliably turn on the IRFZ20 with R_DS(on) ≤ 1.0 Ω, enabling direct drive in low-to-medium frequency applications. However, gate capacitance (Q_g = 16 nC) should be considered for timing margins-especially above 50 kHz-when driving the IRFZ20 from weak GPIO sources.

What is the avalanche energy rating of IRFZ20, and how is it tested?

The IRFZ20 is rated for 125 mJ single-pulse avalanche energy (E_AS) and 5.0 mJ repetitive avalanche energy (E_AR). E_AS is measured under unclamped inductive switching conditions: V_DD = 50 V, starting T_J = 25 °C, L = 6.9 mH, R_g = 25 Ω, and I_AS = 5.2 A. This validates the IRFZ20's ability to absorb inductive energy safely during fault events like short-circuit turn-off or relay coil de-energization.

How does the thermal resistance of IRFZ20 affect PCB layout and heatsinking decisions?

The IRFZ20 has R_thJC = 2.5 °C/W (junction-to-case) and R_thJA = 62 °C/W (junction-to-ambient). Since most heat flows through the drain-connected tab, effective heatsinking is essential: a flat, greased surface yields R_thCS = 0.50 °C/W. Without a heatsink, even modest power dissipation (e.g., 1 W) raises T_J by >60 °C above ambient-so PCB copper area alone is insufficient. Proper mechanical mounting and thermal interface material are mandatory for reliable IRFZ20 operation.