STMicroelectronics STS5N15F3

Overview

STS5N15F3 from STMicroelectronics is an N-channel enhancement-mode power MOSFET in SO-8 package, rated for 150 V drain-source voltage, 5 A continuous drain current at 25 °C, and 0.045 Ω typical R_DS(on) at V_GS = 10 V. It features low gate charge (29 nC), low input capacitance (1300 pF), and is optimized for high-efficiency DC-DC converters.

For engineers reviewing the STS5N15F3 datasheet, STS5N15F3 pinout, STS5N15F3 application, or STS5N15F3 equivalent, key selection criteria include its 150 V breakdown rating, 2.5 W thermal dissipation at T_C = 25 °C, avalanche energy rating of 300 mJ, and SO-8 footprint compatibility with standard PCB layout practices for medium-power switching.

Technical Context

This MOSFET employs ST's STripFET™ III process, delivering reduced R_DS(on) × Q_g figure-of-merit for improved switching efficiency. Its gate threshold voltage (2–4 V) ensures reliable turn-on with standard 3.3 V or 5 V logic-level drivers, while the 20 A pulsed drain current supports short-duration overload conditions.

The device integrates a fast-recovery source-drain diode with t_rr = 110 ns and Q_rr = 498 nC at 150 °C, enabling robust synchronous rectification and inductive load switching. Thermal resistance junction-to-PCB is specified at 50 °C/W on 1-inch² FR-4 board with 2 oz copper.

Key Specifications

Pinout & Package

STS5N15F3 is housed in a surface-mount SO-8 package (also referenced as SOIC-8 or narrow SO-8), with exposed drain pad connected to pins 1, 2, 3, and 4 for enhanced thermal and current handling. The package complies with ECOPACK® environmental standards.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar N-channel 150 V power MOSFET applications.

Compared with IRF640NPbF and STP5NK150Z, STS5N15F3 delivers superior power density and switching efficiency in SO-8 form factor, making it optimal for compact, high-frequency DC-DC stages where thermal management relies on PCB copper rather than discrete heatsinks.

Availability

STS5N15F3 is available at Aetrix Electronics and suitable for DC-DC converters, industrial motor drivers, LED constant-current supplies, and hot-swap controllers requiring stable component supply and long-term design-in support.

Supply support for STS5N15F3 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The STS5N15F3 belongs to ST's STripFET™ III power MOSFET product line, engineered specifically for high-efficiency, medium-voltage switching applications including point-of-load regulators and motor control half-bridges.

FAQ

Is STS5N15F3 suitable for 3.3 V logic-level gate drive?

No. Its gate threshold voltage range is 2–4 V, but full enhancement to achieve 0.045 Ω R_DS(on) requires V_GS ≥ 10 V. Driving with only 3.3 V results in R_DS(on) > 0.5 Ω and excessive conduction loss. A gate driver or level shifter is required for logic-compatible operation.

What is the maximum PCB copper area needed to maintain T_j < 150 °C at 5 A continuous?

With R_thj-pcb = 50 °C/W and P_D ≈ I² × R_DS(on) = 25 × 0.057 = 1.425 W, the junction-to-PCB temperature rise is ~71 °C. To hold T_j ≤ 150 °C at 75 °C ambient, ≥1 inch² of 2 oz copper is required per the datasheet test condition.

Does STS5N15F3 have integrated gate protection?

No. It lacks built-in gate Zener clamping or ESD protection diodes. External 15 V gate-source Zener and series gate resistor (≥10 Ω) are recommended to prevent overvoltage and oscillation during fast switching in noisy environments.

Can STS5N15F3 replace STP16NF15 in existing designs?

Not directly. STP16NF15 is a TO-220 150 V/16 A device with different R_DS(on) (0.12 Ω), Q_g (45 nC), and thermal behavior. STS5N15F3 offers lower current rating but superior power density and SO-8 compatibility-layout redesign and thermal validation are mandatory for substitution.