STMicroelectronics STI6N90K5

Overview

STI6N90K5 from STMicroelectronics is a high-voltage N-channel Power MOSFET using MDmesh™ K5 technology, rated for 900 V V_DS, 0.91 Ω typ. R_DS(on) at V_GS = 10 V and I_D = 3 A, and 6 A continuous drain current at T_C = 25 °C. It features built-in Zener-protected gate, 100% avalanche tested, and targets high-efficiency switching in offline SMPS and PFC stages.

For engineers reviewing the STI6N90K5 datasheet, STI6N90K5 pinout, STI6N90K5 application, or STI6N90K5 equivalent, key selection criteria include its ultra-low Q_g (11 nC), low C_oss (31 pF), rugged dv/dt capability (50 V/ns), and integrated source-drain diode with t_rr = 342 ns at 150 °C - critical for hard-switched and resonant topologies.

Technical Context

This MOSFET employs ST's proprietary vertical MDmesh™ K5 structure to minimize conduction and switching losses simultaneously. Its 1.14 °C/W R_thj-case enables high-power operation in compact I²PAK packages without forced cooling, while the Zener-protected gate (V_(BR)GSO = 30 V) eliminates need for external gate clamping in noisy industrial environments.

The device delivers industry-leading FoM (R_DS(on) × Q_g = 12.2 nΩ·F) and supports unclamped inductive switching up to 2 A repetitive avalanche current. Its 720 V safe operating dv/dt rating and 210 mJ E_AS ensure robustness in overvoltage transients common in 3-phase rectified bus applications.

Key Specifications

Pinout & Package

The STI6N90K5 is housed in an I²PAK (TO-262) package with isolated tab. The metal tab is electrically connected to the drain terminal and serves as primary thermal path to heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STP6N90K5, STI6N90K5 offers better thermal performance and isolation; versus IPP60R099C7, it trades higher R_DS(on) for guaranteed 900 V operation - essential for global-input industrial and EV infrastructure designs.

Availability

STI6N90K5 is available at Aetrix Electronics and suitable for industrial switch-mode power supplies, server & telecom rectifiers, LED streetlight drivers, and EV charger auxiliary supplies requiring stable component supply across extended product lifecycles.

Supply support for STI6N90K5 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 STI6N90K5 belongs to ST's MDmesh™ K5 high-voltage MOSFET product line, engineered specifically for high-efficiency, high-power-density offline power conversion in industrial and infrastructure applications.

FAQ

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

The STI6N90K5 supports 4 A continuous drain current at T_C = 100 °C, as specified in Table 2 of the datasheet. This derating reflects thermal limitations of the I²PAK package and ensures junction temperature remains within the −55 to +150 °C operating range under sustained load conditions.

Does the STI6N90K5 require an external gate resistor for EMI suppression?

Yes - although the device has low intrinsic gate resistance (6.4 Ω), a series gate resistor (typically 4.7–10 Ω) is required to dampen ringing, control dV/dt during switching, and meet EN55022 Class B conducted EMI limits. Layout best practices also mandate short, low-inductance gate traces and local 100 nF ceramic decoupling.

Can the STI6N90K5 replace older MDmesh™ K3 devices in existing designs?

Yes - STI6N90K5 is a direct drop-in replacement for STI6N90K3 in most cases, offering identical pinout, voltage rating, and improved R_DS(on) (0.91 Ω vs 1.05 Ω typ.) and Q_g (11 nC vs 13 nC). Thermal design margins improve slightly due to lower conduction loss, but layout and gate drive remain unchanged.

Is the source-drain diode suitable for synchronous rectification?

No - the integrated body diode has t_rr = 342 ns and Q_rr = 3.13 µC at 25 °C, making it unsuitable for synchronous rectification where fast, low-Q_rr diodes are required. It is optimized for freewheeling in hard-switched topologies, not high-frequency bidirectional conduction.