In high-voltage power conversion and motor control applications, selecting a MOSFET that balances ruggedness, efficiency, and cost is a critical engineering decision. This is not a simple drop-in replacement exercise but a careful evaluation of voltage rating, current capability, switching performance, and thermal management. This article uses two established high-voltage MOSFETs from STMicroelectronics—STF24N60DM2 (in TO-220FP) and STW18NM60ND (in TO-247-3)—as benchmarks. We will analyze their design cores and typical applications, then perform a comparative evaluation with two domestic alternative solutions from VBsemi: VBMB165R20S and VBP16R15S. By clarifying parameter differences and performance orientations, this article aims to provide a clear selection guide for your next high-voltage power design.
Comparative Analysis: STF24N60DM2 (N-channel, TO-220FP) vs. VBMB165R20S
Analysis of the Original Model (STF24N60DM2) Core:
This is a 600V, N-channel MOSFET from STMicroelectronics, featuring the MDmesh DM2 superjunction technology in a TO-220FP package. Its design core is to offer a robust balance of high voltage blocking, good current handling, and low switching losses in a compact, isolated package. Key advantages include: a drain current rating of 18A, a typical on-resistance (RDS(on)) of 175mΩ (200mΩ max @ 10V VGS), and the DM2 technology which optimizes the trade-off between conduction loss and switching performance.
Compatibility and Differences of the Domestic Alternative (VBMB165R20S):
VBsemi's VBMB165R20S is offered in a standard TO-220F package and serves as a functional pin-to-pin compatible alternative for many circuits. The key differences are in the electrical parameters: VBMB165R20S features a higher voltage rating (650V vs. 600V) and a slightly higher continuous drain current (20A vs. 18A). Crucially, its on-resistance is specified at a lower 160mΩ (max @ 10V VGS), promising lower conduction losses. It utilizes a SJ_Multi-EPI (Super Junction Multi-Epitaxial) process.
Key Application Areas:
Original Model STF24N60DM2: Its profile makes it well-suited for compact, cost-sensitive offline power supplies and motor drives requiring up to 18A. Typical applications include:
Switched-Mode Power Supplies (SMPS): PFC stages, flyback, or forward converters in AC-DC adapters and auxiliary power units.
Motor Control: Drives for fans, pumps, and appliances.
Lighting: High-voltage switching in LED drivers and ballasts.
Alternative Model VBMB165R20S: With its higher voltage and current ratings and lower RDS(on), it is suitable for direct replacement or new designs requiring enhanced margin, efficiency, or power density within the same form factor. It's ideal for similar applications where improved conduction loss is beneficial.
Comparative Analysis: STW18NM60ND (N-channel, TO-247-3) vs. VBP16R15S
This comparison focuses on higher-power applications where the larger TO-247 package is used for superior thermal performance.
Analysis of the Original Model (STW18NM60ND) Core:
This 600V N-channel MOSFET from ST is housed in a TO-247-3 package, targeting applications demanding good thermal dissipation. Its core advantage is providing a reliable 13A continuous current in a robust package. The on-resistance is specified at 290mΩ (@ 10V VGS, 6.5A), which is suitable for its target power level.
Compatibility and Differences of the Domestic Alternative (VBP16R15S):
VBsemi's VBP16R15S is a direct package-compatible alternative in the TO-247 form factor. It presents a compelling "performance-enhanced" profile: it offers a higher continuous drain current (15A vs. 13A) and a competitive on-resistance of 280mΩ (max @ 10V VGS). It maintains the same 600V voltage rating and also uses a SJ_Multi-EPI process.
Key Application Areas:
Original Model STW18NM60ND: Its robust TO-247 package and 13A rating make it a solid choice for medium-power industrial applications where thermal management is key. Examples include:
Motor Drives: For larger industrial motors, inverters, and servo drives.
Power Supplies: Higher-output SMPS, UPS systems, and welding equipment.
Energy Conversion: Stages in solar inverters or battery storage systems.
Alternative Model VBP16R15S: With its higher current capability (15A) and similar/low RDS(on), it is an excellent choice for upgrading existing designs or for new projects requiring more current headroom and potentially lower losses within the same thermal package. It fits seamlessly into the same high-power application spaces.
Conclusion
In summary, this analysis reveals clear and viable domestic alternative paths for high-voltage MOSFETs:
For TO-220FP package applications, the original STF24N60DM2 offers a reliable 600V/18A solution with proven MDmesh DM2 technology. Its domestic alternative, VBMB165R20S, provides a pin-compatible option with meaningful performance enhancements—higher voltage (650V), higher current (20A), and lower on-resistance (160mΩ)—making it an attractive choice for efficiency-driven designs or as a robust alternative in the supply chain.
For higher-power TO-247 package applications, the original STW18NM60ND provides a solid 600V/13A foundation. Its domestic alternative, VBP16R15S, offers a direct package replacement with upgraded current handling (15A) and a competitive on-resistance (280mΩ), presenting a valuable option for designs seeking improved performance or sourcing diversification.
The core takeaway is that selection depends on precise requirement matching. In the context of supply chain resilience, these domestic alternatives from VBsemi not only provide qualified backup options but also offer parameter advantages in key areas, giving engineers greater flexibility in design trade-offs and cost optimization. Understanding the specific demands of your voltage, current, and thermal environment is essential to leverage the full value of these components.