MOSFET Selection for High-Voltage Power Applications: STF18NM80, STP13N95K3 vs. China Alternatives VBMB18R20S, VBM19R09S
Comparative Analysis: STF18NM80 (N-channel) vs. VBMB18R20S
Analysis of the Original Model (STF18NM80) Core:
This is an 800V N-channel MOSFET from STMicroelectronics, in a TO-220F package. Its design core is to provide robust high-voltage switching capability. Key advantages are: a high voltage rating of 800V, a continuous drain current of 17A, and an on-resistance of 295mΩ at 10V gate drive.
Compatibility and Differences of the Domestic Alternative (VBMB18R20S):
VBsemi's VBMB18R20S is a direct pin-to-pin compatible alternative in a TO-220F package. The main differences are in electrical parameters: VBMB18R20S offers a similar 800V rating but features a lower on-resistance of 205mΩ@10V and a slightly higher continuous current rating of 20A.
Key Application Areas:
Original Model STF18NM80: Suitable for high-voltage, medium-current switching applications such as:
- SMPS (Switched-Mode Power Supplies) and PFC (Power Factor Correction) circuits.
- Motor drives and inverters.
- Industrial power systems.
Alternative Model VBMB18R20S: Better suited for applications requiring lower conduction loss and higher current capability within the same voltage class, offering an efficiency upgrade.
Comparative Analysis: STP13N95K3 (N-channel) vs. VBM19R09S
Analysis of the Original Model (STP13N95K3) Core:
This is a 950V N-channel MOSFET from STMicroelectronics, in a TO-220 package. It targets very high-voltage applications. Its core strengths are: a 950V drain-source voltage, 10A continuous current, and 680mΩ on-resistance at 10V gate drive.
Compatibility and Differences of the Domestic Alternative (VBM19R09S):
VBsemi's VBM19R09S is a pin-to-pin compatible alternative in a TO-220 package. Key parameter differences: VBM19R09S has a 900V rating, a continuous current of 9A, and an on-resistance of 750mΩ@10V. It offers a slightly lower voltage rating but comparable performance in its class.
Key Application Areas:
Original Model STP13N95K3: Ideal for very high-voltage, lower current applications like:
- Off-line SMPS and lighting ballasts.
- Industrial controls and power supplies.
Alternative Model VBM19R09S: A viable alternative for 900V systems where the specific 950V rating is not strictly required, providing a cost-effective solution with similar package and performance.
In summary, this analysis reveals two selection paths for high-voltage applications:
For 800V class applications, the original STF18NM80 provides reliable 17A capability. Its domestic alternative VBMB18R20S offers enhanced performance with lower RDS(on) and higher current, suitable for efficiency-focused upgrades.
For 900-950V class applications, the original STP13N95K3 serves high-voltage needs. Its domestic alternative VBM19R09S provides a competitive option at 900V with a compatible footprint and characteristics.
The core conclusion is: Selection depends on precise voltage and current requirements. Domestic alternatives like VBMB18R20S and VBM19R09S offer not only supply chain resilience but also performance enhancements or cost benefits, giving engineers greater flexibility in high-voltage design trade-offs.