STMicroelectronics STU9N65M2

Overview

STU9N65M2 from STMicroelectronics is an N-channel 650 V, 0.79 Ω typ. (0.90 Ω max), 5 A Power MOSFET in IPAK (TO-251) package, featuring extremely low gate charge (10.3 nC), optimized COSS profile (109 pF energy-equivalent), and 100% avalanche tested performance - deployed in high-efficiency 650 V AC-DC flyback and PFC stages.

For engineers reviewing the STU9N65M2 datasheet, STU9N65M2 pinout, STU9N65M2 application, or STU9N65M2 equivalent, key selection criteria include its 50 V/ns dv/dt ruggedness, 1.6 V body diode forward voltage at 5 A, 276 ns reverse recovery time, and thermal resistance of 2.08 °C/W junction-to-case - critical for thermally constrained industrial SMPS designs.

Technical Context

This MDmesh M2 technology MOSFET uses a strip layout and enhanced vertical structure to simultaneously reduce RDS(on) and output capacitance, enabling high-frequency switching with low conduction and capacitive losses. Its Zener-protected gate ensures robust ESD immunity up to ±25 V.

The device delivers 105 mJ single-pulse avalanche energy and supports unclamped inductive switching up to 1 A repetitive avalanche current. Its 15 V/ns diode recovery dv/dt rating and 50 V/ns MOSFET dv/dt ruggedness are validated under defined test conditions (VDS ≤ 520 V).

Key Specifications

Pinout & Package

STU9N65M2 is housed in an IPAK (TO-251) package with three terminals: Drain (Tab), Gate (Pin 1), Source (Pin 3). The metal tab is electrically connected to the Drain and serves as the primary thermal path.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 650 V Power MOSFET applications.

Compared with STP9N65M2 and STF9N65M2, STU9N65M2 offers identical electrical performance in a surface-mount IPAK package with superior thermal resistance (2.08 °C/W) and minimal PCB footprint - making it optimal for high-power-density industrial and automotive-grade power supplies where thermal management and layout compactness are critical.

Availability

STU9N65M2 is available at Aetrix Electronics and suitable for industrial AC-DC adapters, server PSU primary switches, and EV onboard charger PFC stages requiring stable component supply and long-term manufacturing continuity.

Supply support for STU9N65M2 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.

STU9N65M2 belongs to the MDmesh M2 Power MOSFET product line, engineered specifically for high-efficiency, high-voltage switching in 650 V offline power conversion systems including PFC, flyback, and resonant topologies.

FAQ

What is the maximum continuous drain current for STU9N65M2 at 100 °C case temperature?

The maximum continuous drain current is 3.2 A at T_C = 100 °C, as specified in Table 1 of DS10197 Rev 3. This rating is limited by package thermal constraints, not silicon capability, and assumes proper heatsinking to maintain case temperature at or below 100 °C.

Does STU9N65M2 require external gate protection?

No - STU9N65M2 integrates a Zener diode between gate and source, providing ±25 V gate-body voltage clamping. This eliminates the need for external gate protection components in typical 10 V gate drive applications, provided layout minimizes gate loop inductance.

How does the 109 pF C_oss,eq value impact hard-switched converter efficiency?

C_oss,eq = 109 pF defines the effective capacitance governing turn-off energy loss (E_off ≈ ½ × C_oss,eq × V_DS²). At 400 V bus voltage, this yields <2 µJ per switching cycle - directly reducing switching loss in 100 kHz flyback or PFC stages by ~15% versus legacy 650 V MOSFETs with >200 pF C_oss,eq.

Can STU9N65M2 be used in place of STP9N65M2 without layout changes?

No - STU9N65M2 uses IPAK (TO-251) surface-mount packaging, while STP9N65M2 uses through-hole TO-220. Direct substitution requires redesigning the PCB footprint, thermal pad, and gate/source routing. However, electrical characteristics and thermal performance (R_thj-case) are identical between the two packages.