STMicroelectronics STL85N6F3

Overview

STL85N6F3 from STMicroelectronics is an N-channel enhancement-mode Power MOSFET in PowerFLAT™ 5x6 package, rated for 60 V drain-source voltage, 0.0057 Ω typical R_DS(on) at V_GS = 10 V and I_D = 8.5 A, and 19 A continuous drain current at T_C = 25°C. It delivers low conduction loss and rugged unclamped inductive switching capability for high-efficiency DC-DC converters and motor control stages.

For engineers reviewing the STL85N6F3 datasheet, STL85N6F3 pinout, STL85N6F3 application, or STL85N6F3 equivalent, key selection criteria include its 1.56 °C/W junction-to-case thermal resistance, 49.8 nC total gate charge, 100% avalanche-tested ruggedness, and compatibility with FR-4 PCB layouts using the recommended 4.2 mm × 3.5 mm exposed pad footprint.

Technical Context

This MOSFET employs ST's StripFET™ V technology with single-feature-size strip layout, enabling high cell density and reproducible manufacturing. Its design targets low R_DS(on) and low Q_g, supporting fast switching in synchronous buck converters and half-bridge motor drivers.

The device features a built-in source-drain diode with 1.3 V forward voltage at 19 A and 53.6 ns reverse recovery time under specified conditions (I_SD = 19 A, di/dt = 100 A/μs, V_DD = 48 V, T_j = 150°C), making it suitable for freewheeling paths where controlled body-diode conduction is required.

Key Specifications

Pinout & Package

STL85N6F3 uses the PowerFLAT™ 5x6 surface-mount package with an exposed drain pad on the bottom side for thermal and electrical connection. The package has 5 terminals: three drain pins (D), one source (S), and one gate (G), arranged in a single-row configuration with pin 1 marked by a dot or notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRF8720PBF and DMT6009LPS, STL85N6F3 offers superior avalanche ruggedness and optimized thermal performance on standard FR-4, making it preferred for compact, high-reliability industrial power stages where unclamped inductive loads are present.

Availability

STL85N6F3 is available at Aetrix Electronics and suitable for DC-DC converters, motor drives, LED drivers, and hot-swap controllers requiring stable component supply and long-term industrial lifecycle support.

Supply support for STL85N6F3 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, specializing in power management, microcontrollers, sensors, and automotive ICs.

The STL85N6F3 belongs to ST's Power MOSFET portfolio designed specifically for high-current, high-efficiency industrial and consumer power conversion, emphasizing ruggedness, thermal performance, and manufacturability in surface-mount formats.

FAQ

What is the maximum safe operating temperature for STL85N6F3?

The STL85N6F3 has a maximum operating junction temperature of 150°C and a storage temperature range of –55°C to +150°C. Its thermal resistance junction-to-case is 1.56 °C/W, so with a 50°C case temperature rise, power dissipation must be limited to ~32 W to stay within the 150°C limit. Derating begins at 25°C ambient at 0.03 W/°C.

Can STL85N6F3 be driven directly by a 3.3 V microcontroller GPIO?

No - while its gate threshold voltage starts at 2 V (min), full enhancement requires ≥10 V for guaranteed 0.0065 Ω R_DS(on). Driving with 3.3 V yields high R_DS(on) (>0.05 Ω) and excessive conduction loss. A dedicated gate driver (e.g., STMicroelectronics TD350) or level-shifting circuit is required for reliable switching.

Does STL85N6F3 have integrated ESD protection on the gate?

The STL85N6F3 does not include on-die ESD protection diodes. Its gate oxide is rated for ±20 V absolute maximum V_GS, and gate-body leakage is ±200 nA at ±20 V. External gate resistors (≤100 Ω) and TVS diodes are recommended in production designs to prevent ESD damage during handling and PCB assembly.

Is the exposed pad on the PowerFLAT™ 5x6 package electrically connected?

Yes - the exposed pad is internally connected to the drain (D) terminal and must be soldered to a large copper pour on the PCB for both thermal conduction and electrical functionality. Thermal vias to inner ground or power planes are strongly recommended to achieve the specified 1.56 °C/W R_thj-case and avoid thermal runaway under sustained 19 A loads.