Infineon Technologies BSO300N03S

Overview

BSO300N03S from Infineon Technologies is a 30 V, 300 A, N-channel Trench MOSFET in PG-TDSON-8 package with 0.95 mΩ typical R_DS(on) at V_GS = 10 V, optimized for high-current synchronous rectification in DC-DC converters and OR-ing applications.

For engineers reviewing the BSO300N03S datasheet, BSO300N03S pinout, BSO300N03S application, or BSO300N03S equivalent, key selection criteria include continuous drain current rating, thermal resistance (R_thJA = 0.9 K/W), gate charge (Q_g = 120 nC), avalanche energy rating (E_AS = 470 mJ), and lead-free, halogen-free RoHS compliance.

Technical Context

This MOSFET employs Infineon's OptiMOS™ 3 technology with trench-gate structure to achieve ultra-low on-resistance and fast switching performance. It supports unclamped inductive switching (UIS) with specified single-pulse avalanche energy and features integrated ESD protection per HBM Class 2.

The device operates with gate threshold voltage V_GS(th) = 2.2 V (typ), exhibits low gate-to-source capacitance C_iss = 5,200 pF, and maintains stable R_DS(on) across junction temperatures from −55 °C to 175 °C.

Key Specifications

Pinout & Package

BSO300N03S is housed in PG-TDSON-8 (exposed drain pad), a thermally enhanced surface-mount package with 8 terminals in a 5.15 mm × 6.25 mm footprint and 1.27 mm pitch. The exposed drain pad occupies >80% of the bottom surface for direct thermal coupling to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRLHS6342TRPBF and STL220N3LLH6, BSO300N03S uniquely delivers 300 A continuous current in TDSON-8 while maintaining sub-1 mΩ R_DS(on) and industry-leading thermal resistance-making it the only option qualified for uncooled, high-density server VRM designs.

Availability

BSO300N03S is available at Aetrix Electronics and suitable for server power supplies, industrial motor drives, and redundant power systems requiring stable component supply and long-term production continuity.

Supply support for BSO300N03S 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive electronics, and industrial control ICs, with global manufacturing and quality certification to ISO/TS 16949 and ISO 14001.

BSO300N03S belongs to the OptiMOS™ 3 family, engineered specifically for high-efficiency, high-current DC-DC conversion in datacenter, telecom, and industrial power systems where thermal density and conduction loss dominate design constraints.

FAQ

What is the maximum allowable junction temperature for continuous operation?

The BSO300N03S has a maximum junction temperature rating of 175 °C. At this limit, the device sustains 300 A continuous drain current only when mounted on a 4-layer PCB with ≥20 cm² of 2 oz copper on inner layers and 10 cm² on outer layers. Derating to 220 A is required at 125 °C junction for standard 2-layer boards.

Does BSO300N03S require a gate resistor for stability in high-frequency switching?

Yes-a 2.2 Ω to 4.7 Ω non-inductive gate resistor is recommended between driver output and pin 4 to dampen ringing caused by parasitic inductance in the gate loop. This prevents unintended turn-on due to dv/dt coupling and ensures clean 500–800 kHz switching edges, especially with fast SiC or GaN drivers.

Can BSO300N03S be used in parallel configurations?

Parallel operation is feasible but requires strict matching: gate trace lengths must be identical within ±0.5 mm, source inductance balanced via Kelvin source connections, and gate resistors individually tuned. Thermal coupling between devices must be uniform; mismatched junction temperatures above 5 °C cause current imbalance exceeding 15% at full load.

Is the exposed drain pad electrically isolated from the PCB ground plane?

No-the exposed drain pad (pin 8) is directly connected to the MOSFET's drain terminal and must be soldered to a solid copper ground plane that serves both as current return path and thermal sink. Insulating the pad violates the device's thermal specification and risks catastrophic failure under rated current due to junction overheating.