MOSFET Selection for High-Voltage Power Applications: STP27N60M2-EP, STP6N80K5 vs. China Alternatives VBM16R20S, VBM18R05S
In high-voltage power conversion and switching designs, 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, conduction loss, switching performance, and supply chain stability. This article takes two representative high-voltage MOSFETs—STP27N60M2-EP (600V) and STP6N80K5 (800V)—as benchmarks, analyzes their design focus and typical applications, and compares them with two domestic alternative solutions, VBM16R20S and VBM18R05S. By clarifying parameter differences and performance orientation, we provide a clear selection guide to help you find the optimal power switching solution in your next high-voltage design.
Comparative Analysis: STP27N60M2-EP (600V N-channel) vs. VBM16R20S
Analysis of the Original Model (STP27N60M2-EP) Core:
This is a 600V N-channel MOSFET from STMicroelectronics, in a standard TO-220-3 package. Its design focuses on reliable performance in medium-power, high-voltage applications. Key advantages include: a drain-source voltage (Vdss) of 600V, a continuous drain current (Id) of 20A, and an on-resistance (RDS(on)) of 163mΩ at 10V gate drive. It is built on an advanced Multi-EPI process, offering a good balance between breakdown voltage and conduction loss.
Compatibility and Differences of the Domestic Alternative (VBM16R20S):
VBsemi's VBM16R20S is a direct pin-to-pin compatible alternative in a TO-220 package. The key parameters are highly aligned: both are 600V N-channel devices with a 20A continuous current rating. The on-resistance of VBM16R20S is specified at 160mΩ (@10V), slightly lower than the original's 163mΩ, potentially offering marginally lower conduction loss. Both devices use a Super Junction Multi-EPI (SJ_Multi-EPI) technology.
Key Application Areas:
Original Model STP27N60M2-EP: Well-suited for 600V-class medium-power switching applications requiring robust performance.
Switched-Mode Power Supplies (SMPS): PFC (Power Factor Correction) stages, flyback, or forward converters in AC-DC power supplies.
Motor Drives: Inverter stages for driving motors in appliances, fans, or pumps.
Industrial Controls: General-purpose high-voltage switching and energy conversion.
Alternative Model VBM16R20S: Serves as a highly compatible alternative for the same 600V application spaces, providing a reliable second source with equivalent or slightly improved conduction performance.
Comparative Analysis: STP6N80K5 (800V N-channel) vs. VBM18R05S
This comparison shifts to higher voltage tiers, where the design priority is high blocking voltage capability combined with controlled conduction loss.
Analysis of the Original Model (STP6N80K5) Core:
This 800V N-channel MOSFET from STMicroelectronics uses the MDmesh K5 technology in a TO-220 package. Its core advantages are:
High Voltage Rating: A Vdss of 800V makes it suitable for off-line applications and harsh voltage environments.
Optimized Technology: The MDmesh K5 platform aims to reduce RDS(on) Area (specific on-resistance) and improve switching performance.
Application-Tailored: With a continuous current of 4.5A and an RDS(on) of 1.6Ω (@10V), it targets lower-current, high-voltage switching needs.
Compatibility and Differences of the Domestic Alternative (VBM18R05S):
VBsemi's VBM18R05S is a direct pin-to-pin compatible alternative for 800V applications. It shows a performance-enhanced profile in key parameters:
Same High Voltage: 800V drain-source voltage rating.
Higher Current Rating: A continuous drain current of 5A, compared to the original's 4.5A.
Lower On-Resistance: An RDS(on) of 1300mΩ (1.3Ω) at 10V, significantly lower than the original's 1.6Ω. This translates to substantially reduced conduction losses.
Key Application Areas:
Original Model STP6N80K5: Ideal for applications requiring an 800V breakdown margin with moderate current.
Off-line Power Supplies: Main switches in flyback converters for adapters, LED drivers, or auxiliary power supplies.
Lighting: Electronic ballasts and LED driver circuits.
Industrial Switching: Where 800V rating provides necessary safety margin.
Alternative Model VBM18R05S: A superior performance alternative for the same 800V application spaces. Its lower RDS(on) and higher current capability make it excellent for upgrading designs for higher efficiency, lower heat generation, or handling slightly higher power within the same form factor.
Conclusion
In summary, this analysis reveals two clear substitution paths for high-voltage MOSFETs:
For 600V medium-power applications, the original STP27N60M2-EP offers reliable performance with a 20A current rating and 163mΩ on-resistance. Its domestic alternative VBM16R20S provides a highly compatible, pin-to-pin replacement with essentially identical electrical characteristics (600V, 20A, 160mΩ), serving as a dependable second-source option.
For 800V applications, the original STP6N80K5 (800V, 4.5A, 1.6Ω) meets basic high-voltage switching needs. Its domestic alternative VBM18R05S presents a compelling performance-enhanced choice. With the same 800V rating, it offers a higher 5A current and a significantly lower 1.3Ω on-resistance, enabling designs with improved efficiency and thermal performance.
The core takeaway is that selection depends on precise requirement matching. In the landscape of supply chain diversification, domestic alternatives like VBM16R20S and VBM18R05S not only provide viable backup sources but also, in the case of VBM18R05S, deliver superior parameters. This gives engineers greater flexibility and resilience in design trade-offs and cost optimization. Understanding the design focus and parameter implications of each device is key to unlocking its full potential in your circuit.