STMicroelectronics STD35NF3LLT4

Overview

STD35NF3LLT4 from STMicroelectronics is an N-channel 30V, 35A DPAK Power MOSFET with R_DS(on) = 0.014 Ω @ V_GS = 10V and Q_g = 42 nC, optimized for high-efficiency synchronous buck converters in motherboard VRMs and DC-DC power stages.

For engineers reviewing the STD35NF3LLT4 datasheet, STD35NF3LLT4 pinout, STD35NF3LLT4 application, or STD35NF3LLT4 equivalent, key selection criteria include gate charge vs. conduction loss trade-off at 4.5V drive, avalanche energy rating (300 mJ), thermal resistance (R_thj-case = 3 °C/W), and DPAK package compatibility with high-current PCB layouts.

Technical Context

This STripFET™ II MOSFET uses a single-feature-size strip-based process to achieve optimal R_DS(on) × Q_g balance at low gate drive voltages (4.5V), enabling efficient operation in both high-side and low-side switching positions of synchronous buck regulators.

Its 30V V_DS, 35A continuous drain current (T_C = 25°C), and 140A pulsed rating support high-current transient handling; integrated body diode exhibits t_rr = 35 ns and Q_rr = 44 nC at 150°C, critical for minimizing recovery losses in hard-switched topologies.

Key Specifications

Pinout & Package

DPAK (TO-252) package: surface-mount, 3-pin, single-die layout with exposed drain pad for thermal and electrical connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRF6614TRPBF and STL37N3LLH6, STD35NF3LLT4 offers the best balance of DPAK manufacturability, 3 °C/W thermal resistance, and proven reliability in high-volume motherboard VRMs-making it ideal for cost-sensitive, high-reliability industrial and computing power stages.

Availability

STD35NF3LLT4 is available at Aetrix Electronics and suitable for server VRMs, laptop CPU voltage regulators, industrial PLC I/O modules, and automotive body control units requiring stable component supply and long-term production continuity.

Supply support for STD35NF3LLT4 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 analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The STD35NF3LLT4 belongs to ST's STripFET™ II Power MOSFET product line, engineered specifically for high-frequency, high-efficiency DC-DC conversion in computing and communications infrastructure where thermal performance and gate drive simplicity are critical.

FAQ

Is STD35NF3LLT4 suitable for 5V gate drive applications?

Yes. Its gate threshold voltage (V_GS(th)) ranges from 1.0 V to 2.5 V, and R_DS(on) is specified at V_GS = 4.5 V (0.016 Ω max), confirming full enhancement with standard 5V logic-level drivers without requiring gate boosting.

What is the maximum safe operating temperature for continuous operation?

The device supports continuous operation up to T_j = 175°C, with derated current of 25A at T_C = 100°C. Junction-to-case thermal resistance is 3 °C/W, so maintaining case temperature ≤95°C ensures junction stays within limit under 35A DC load.

Does STD35NF3LLT4 have built-in ESD protection?

No. The datasheet does not specify on-chip ESD protection structures. Gate-body leakage (±100 nA at ±16 V) and absolute maximum V_GS = ±16 V indicate standard MOSFET gate oxide sensitivity; external TVS or series resistance is recommended in handling and circuit design.

Can STD35NF3LLT4 replace older STD35NF3L in existing designs?

Yes. STD35NF3LLT4 is the tape-and-reel variant of STD35NF3LL (same die, same DPAK package, identical electrical specs). The "T4" suffix denotes packaging only; no electrical or thermal differences exist between STD35NF3LL and STD35NF3LLT4.