STMicroelectronics STD5N80K5

Overview

STD5N80K5 from STMicroelectronics is an N-channel 800 V, 1.75 Ω (max) MDmesh K5 Power MOSFET in DPAK (TO-252) package, rated for 4 A continuous drain current at 25 °C and 100% avalanche tested. It features ultra-low gate charge (5 nC typ.), Zener-protected gate-source terminals, and 1.5 V source-drain forward voltage at 4 A - optimized for high-voltage flyback and resonant SMPS topologies.

For engineers reviewing the STD5N80K5 datasheet, STD5N80K5 pinout, STD5N80K5 application, or STD5N80K5 equivalent, key selection criteria include R_DS(on) × area efficiency, dv/dt ruggedness (50 V/ns), single-pulse avalanche energy (165 mJ), and thermal resistance junction-to-case (2.08 °C/W) in compact DPAK mounting.

Technical Context

This device employs ST's proprietary MDmesh K5 vertical superjunction architecture to achieve industry-leading figure of merit (R_DS(on) × Q_g) and reduced output capacitance (C_oss = 15 pF). Its 800 V breakdown voltage and 4.5 V/ns diode recovery dv/dt rating support robust operation in hard-switched PFC and offline converters.

The integrated back-to-back gate-source Zener diodes (V_(BR)GSO = 30 V) eliminate need for external clamping, while 1.2 A repetitive avalanche current rating enables reliable unclamped inductive switching without snubbers in auxiliary supplies and LED drivers.

Key Specifications

Pinout & Package

DPAK (TO-252) package with exposed drain tab (pin 2) for thermal and electrical connection; standard 3-pin configuration with G-S-D layout. Tab is electrically connected to drain terminal and must be soldered to PCB copper pour for thermal management.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage power MOSFET applications.

Compared with STP5N80 and IPP60R190C6, STD5N80K5 uniquely delivers 800 V capability with Zener gate protection, 165 mJ avalanche energy, and best-in-class R_DS(on) × Q_g - making it the only qualified choice for compact, high-reliability 24–48 W offline SMPS where safety margins and thermal density are critical.

Availability

STD5N80K5 is available at Aetrix Electronics and suitable for AC/DC adapters, industrial flyback converters, and LED driver secondary switches requiring stable component supply across extended product lifecycles.

Supply support for STD5N80K5 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 automotive, industrial, and consumer markets.

STD5N80K5 belongs to ST's MDmesh K5 high-voltage Power MOSFET product line, engineered specifically for high-efficiency, high-power-density offline SMPS in space- and reliability-constrained applications.

FAQ

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

The STD5N80K5 supports 2.3 A continuous drain current when the case temperature is maintained at 100 °C, as specified in Table 1 of DS11344 Rev 4. This derating reflects thermal limits of the DPAK package and must be verified against actual PCB copper area and airflow in the final design.

Does the device include internal gate protection, and what is its breakdown voltage?

Yes - STD5N80K5 integrates back-to-back Zener diodes between gate and source with a specified breakdown voltage of 30 V (I_GS = ±1 mA), per Table 8. This eliminates need for external gate clamps and enhances ESD robustness without adding components or board area.

Can STD5N80K5 replace older STD5NK80Z devices in existing designs?

No - STD5NK80Z uses MDmesh Z technology with different dynamic parameters: higher Q_g (12 nC), higher R_DS(on) (2.2 Ω), and no Zener gate protection. Direct replacement requires revalidation of gate drive timing, thermal performance, and avalanche margin due to these measurable differences.

What is the recommended PCB footprint for thermal performance in DPAK mounting?

Per Figure 21 in DS11344 Rev 4, the recommended DPAK (TO-252) footprint uses a minimum 1-inch² copper pour on the drain tab side, 2 oz Cu thickness, to achieve the specified R_thj-pcb of 50 °C/W. Smaller pads increase junction temperature and reduce safe operating area.