STMicroelectronics STW24NK55Z

Overview

STW24NK55Z from STMicroelectronics is an N-channel Zener-protected SuperMESH™ power MOSFET rated for 550 V drain-source voltage, 0.18 Ω typical R_DS(on) at V_GS = 10 V, 23 A continuous drain current at T_C = 25 °C, and 285 W total power dissipation - designed for high-voltage switching in industrial SMPS, motor drives, and lighting ballasts.

For engineers reviewing the STW24NK55Z datasheet, STW24NK55Z pinout, STW24NK55Z application, or STW24NK55Z equivalent, key selection considerations include its 4.5 V/ns peak diode recovery dv/dt capability, 100% avalanche tested ruggedness, low 130 nC total gate charge, integrated gate-source Zener protection (±30 V), and TO-247 package thermal performance (R_thj-case = 0.44 °C/W).

Technical Context

The STW24NK55Z implements ST's SuperMESH™ topology - an optimized strip-based PowerMESH™ layout that simultaneously reduces R_DS(on) and enhances dv/dt immunity beyond standard high-voltage MOSFETs. Its internal gate-source Zener diodes (BVGSO = 30 V) provide built-in transient suppression without external components.

It delivers 400 mJ single-pulse avalanche energy (E_AS) at T_j = 25 °C with 23 A avalanche current, and exhibits low dynamic capacitances: C_iss = 4397.5 pF, C_oss = 480.5 pF, and C_rss = 116 pF at V_DS = 25 V - enabling fast, efficient hard-switching up to 100 kHz in offline converters.

Key Specifications

Pinout & Package

Supplied in a through-hole TO-247 package with isolated tab (drain-connected), offering high thermal conductivity and mechanical robustness for industrial power stages.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STW20NK50Z, the STW24NK55Z provides higher voltage margin and lower R_DS(on) for 400 V AC systems; versus IPP60R190C6, it trades slightly higher Q_g for built-in gate protection and proven avalanche ruggedness - making it preferable for cost-sensitive, thermally constrained industrial inverters.

Availability

STW24NK55Z is available at Aetrix Electronics and suitable for industrial SMPS, AC motor drives, electronic ballasts, and UPS output stages requiring stable component supply and long-term manufacturability assurance.

Supply support for STW24NK55Z 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 SuperMESH™ MOSFET product line targets high-reliability, high-voltage switching applications - specifically engineered to deliver low R_DS(on), high dv/dt immunity, and avalanche ruggedness in cost-sensitive industrial power conversion.

FAQ

Is STW24NK55Z RoHS-compliant and lead-free?

Yes. STW24NK55Z is supplied in an ECOPACK®-compliant TO-247 package with lead-free second-level interconnect, meeting RoHS Directive 2011/65/EU requirements. The inner box label explicitly marks the lead-free status per JEDEC JESD97 standards.

What is the maximum safe operating area (SOA) limitation at 100 °C case temperature?

At T_C = 100 °C, the continuous drain current is derated to 10.35 A (per Table 2), and the SOA is bounded by thermal limits - the device supports 23 A pulsed (I_DM) only for pulse widths ≤10 µs at this temperature, as defined by the SOA curve in Figure 2 of the datasheet.

Can STW24NK55Z be used in synchronous rectification topologies?

No. STW24NK55Z is not optimized for synchronous rectification: its body diode has relatively high V_SD (1.6 V at 23 A) and slow reverse recovery (508 ns trr), resulting in excessive conduction and switching losses compared to dedicated SR MOSFETs with low V_F and fast trr.

Does the integrated gate Zener protect against negative V_GS transients?

Yes. The built-in back-to-back Zener diodes clamp both positive and negative gate-source voltages to ±30 V (BVGSO = 30 V), protecting against negative transients such as Miller-induced undershoot during high-di/dt switching - eliminating need for external bidirectional TVS or Zener networks.