STMicroelectronics STK38N3LLH5

Overview

STK38N3LLH5 from STMicroelectronics is an N-channel 30 V, 38 A PolarPAK® STripFET™ V Power MOSFET with 1.3 mΩ R_DS(on) at V_GS = 10 V, 70.9 nC·mΩ R_DS(on)×Q_g figure-of-merit, and ultra-low top-side thermal resistance (0.8 °C/W). It serves as a high-efficiency synchronous rectifier or main switch in compact DC-DC converters for telecom and server power supplies.

For engineers reviewing the STK38N3LLH5 datasheet, STK38N3LLH5 pinout, STK38N3LLH5 application, or STK38N3LLH5 equivalent, key selection criteria include its chip-scale PolarPAK® package, 1.3 mΩ on-resistance at 10 V gate drive, 41.7 nC total gate charge, 750 mJ single-pulse avalanche energy, and junction-to-case thermal resistance of 0.8 °C/W (top drain).

Technical Context

This device implements ST's 5th-generation STripFET™ V process in a fully encapsulated PolarPAK® package, enabling dual-sided thermal dissipation via top-drain and source terminals. Its low R_DS(on)×Q_g metric targets high-frequency switching in point-of-load regulators.

The MOSFET features a 100% matte tin finish compliant with RoHS Directive 2002/95/EC, integrated source-drain diode with 43.2 ns reverse recovery time, and guaranteed operation from –55 °C to 150 °C junction temperature.

Key Specifications

Pinout & Package

PolarPAK® is a 5-pin, chip-scale package with exposed top-side drain (D), source (S) on bottom side, and gate (G) on the periphery. The package enables dual thermal paths: top-side drain to heatsink or copper plane, and bottom-side source to PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SiR626DP and BSC014N04LS6, STK38N3LLH5 offers the lowest R_DS(on)×Q_g product (70.9 nC·mΩ), best top-side thermal performance (0.8 °C/W), and smallest footprint-making it optimal for space-constrained, high-frequency DC-DC designs where thermal headroom and switching loss are critical.

Availability

STK38N3LLH5 is available at Aetrix Electronics and suitable for telecom power supplies, server VRMs, industrial motor drives, and automotive ADAS power modules requiring stable component supply and long-lifecycle support.

Supply support for STK38N3LLH5 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.

The STripFET™ V product line delivers high-current, low-voltage power MOSFETs optimized for high-efficiency, high-power-density switching applications including DC-DC converters, motor controls, and power supplies.

FAQ

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

The STK38N3LLH5 supports 23.75 A continuous drain current when the case temperature is maintained at 100 °C, as specified in Table 2 of the official datasheet (Doc ID 14462 Rev 4). This rating assumes mounting on an FR-4 board with 1 inch² copper area and 2 oz. thickness, and accounts for thermal derating beyond 25 °C ambient.

Does STK38N3LLH5 have integrated avalanche energy rating?

Yes, STK38N3LLH5 is rated for 750 mJ single-pulse avalanche energy (E_AS) under defined test conditions: starting junction temperature of 25 °C, I_D = 22 A, and V_DD = 50 V. This value is measured per JEDEC JESD24-1 and confirms robustness against inductive switching transients without external clamping.

Is the PolarPAK® package RoHS-compliant and lead-free?

Yes, STK38N3LLH5 features a 100% matte tin (Sn) finish compliant with the European RoHS Directive 2002/95/EC. The device is qualified for lead-free reflow soldering profiles, with no lead content in terminations or internal construction, and meets ST's ECOPACK® environmental specifications.

Can STK38N3LLH5 be used with 4.5 V gate drive in logic-level applications?

Yes, STK38N3LLH5 specifies R_DS(on) = 1.7 mΩ max at V_GS = 4.5 V and I_D = 19 A (Table 4), confirming full enhancement with standard 4.5 V logic-level drivers. Its gate threshold voltage range (1–2.5 V) ensures reliable turn-on even with marginal gate drive margins.