STMicroelectronics STS4DNFS30L

Overview

STS4DNFS30L from STMicroelectronics is an N-channel 30 V Power MOSFET integrated with a co-packaged Schottky rectifier in a single SO-8 package. It delivers R_DS(on) = 0.044 Ω @ V_GS = 10 V, 4 A continuous drain current, and 3 A average forward current from the Schottky diode. It is designed for synchronous rectification and DC-DC converter output stages in portable power supplies.

For engineers reviewing the STS4DNFS30L datasheet, STS4DNFS30L pinout, STS4DNFS30L application, or STS4DNFS30L equivalent, key selection criteria include its dual-function integration (MOSFET + Schottky), low 0.044 Ω on-resistance, 30 V V_DS/V_RRM rating, thermal resistance of 62.5 °C/W, and SO-8 surface-mount compatibility for high-density board layouts.

Technical Context

This device implements a monolithic integration strategy where a low-voltage STripFET™ III MOSFET and a low-drop Schottky diode share a common source terminal in a single SO-8 outline. The MOSFET features gate threshold voltage of 1 V (min), enabling 5 V logic-level drive, while the Schottky exhibits V_F(max) = 0.51 V at 3 A and reverse recovery time t_rr = 35 ns.

The internal configuration supports synchronous buck topologies by placing the Schottky's anode at the drain node and cathode at the source, allowing it to clamp inductive kickback and conduct freewheeling current during MOSFET off-time. Safe operating area (SOA) is defined up to 16 A pulsed drain current with 100 µs pulse width and 1.5% duty cycle.

Key Specifications

Pinout & Package

STS4DNFS30L uses the industry-standard SO-8 package (4.9 mm × 6.0 mm × 1.75 mm height), compliant with ECOPACK® environmental specifications. Pin numbering follows JEDEC MS-012AC, with pins 1–4 on one side and 5–8 on the other.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar integrated MOSFET + Schottky applications.

Compared with STS4DNFS30L, STP4NK60Z lacks integration and operates at incompatible voltage levels, while IRF7470PBF increases BOM cost and board area due to mandatory external diode-neither offers the combined efficiency, space, and thermal advantages of the co-packaged solution.

Availability

STS4DNFS30L is available at Aetrix Electronics and suitable for printer power supplies, USB-C PD adapters, portable medical monitors, and smartphone charging circuits requiring stable component supply and legacy-compatible SO-8 footprints.

Supply support for STS4DNFS30L 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, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

This device belongs to ST's STripFET™ Power MOSFET product line, engineered specifically for high-efficiency, space-constrained DC-DC conversion in portable and battery-powered systems.

FAQ

Is STS4DNFS30L still in active production?

No-STS4DNFS30L is marked as Obsolete in ST's official documentation (Doc ID 8566 Rev 5, June 2011). Aetrix Electronics maintains limited legacy stock for design continuity and repair programs but does not offer long-term production supply. Customers should consult ST's current portfolio for pin-compatible replacements such as the STP4N3LLH6 or contact Aetrix for obsolescence mitigation support.

Can STS4DNFS30L be used in synchronous rectification mode?

Yes-its integrated Schottky diode shares the source terminal with the MOSFET, enabling true synchronous rectification. When the MOSFET is off, the Schottky conducts freewheeling current; when on, it blocks reverse current. This eliminates body-diode conduction loss and reduces total power dissipation in buck converters operating above 300 kHz.

What is the maximum safe operating frequency for STS4DNFS30L?

Based on measured t_r = 100 ns and t_f = 22 ns, plus t_rr = 35 ns, the device supports reliable operation up to 1 MHz in hard-switched buck topologies. Efficiency remains >90% at 500 kHz with proper gate drive strength (R_G ≤ 4.7 Ω) and layout minimizing parasitic inductance.

Does STS4DNFS30L require a heatsink in typical applications?

No-its R_thj-a = 62.5 °C/W on FR-4 allows operation up to 4 A continuous current without a heatsink when using ≥2 oz copper and ≥2 cm² thermal pad. At 2 A, junction temperature rise is ~125°C/W × 0.044 Ω × (2 A)² ≈ 22°C above ambient, well within the –55°C to 150°C operating range.