In modern circuit design, balancing performance, cost, and supply chain stability requires careful MOSFET selection across different power tiers. This article takes two classic MOSFETs from Nexperia—the medium-power BUK72150-55A,118 (N-channel) and the signal-level BSN20BKR (N-channel)—as benchmarks. We will delve into their design cores and typical applications, then evaluate the domestic alternative solutions VBE1695 and VB162K. By comparing parameter differences and performance orientations, we provide a clear selection guide to help you find the optimal power switching solution for your next project.
Comparative Analysis: BUK72150-55A,118 (N-channel) vs. VBE1695
Analysis of the Original Model (BUK72150-55A,118) Core:
This is a 55V N-channel MOSFET from Nexperia in a DPAK package. It is designed for reliable switching in medium-power applications. Its key features include a continuous drain current (Id) of 11A and an on-resistance (RDS(on)) of 127mΩ at 10V gate drive. This balance of voltage rating, current capability, and moderate RDS(on) makes it a robust choice for various power control tasks.
Compatibility and Differences of the Domestic Alternative (VBE1695):
VBsemi's VBE1695, in a TO-252 package (similar footprint to DPAK), serves as a pin-to-pin compatible alternative with enhanced performance. The main differences are electrical: VBE1695 offers a slightly higher voltage rating (60V) and a significantly lower on-resistance—73mΩ at 10V vs. 127mΩ. Its continuous current rating is also higher at 18A compared to 11A.
Key Application Areas:
Original Model BUK72150-55A,118: Ideal for medium-current switching and control in 12V, 24V, or 48V systems where robustness is key. Typical applications include:
DC-DC converter switches (non-synchronous buck/boost).
Load and relay drivers in industrial controls.
Motor drive circuits for small fans or pumps.
Alternative Model VBE1695: Better suited for applications requiring lower conduction losses and higher current capacity within a similar voltage range. It's an excellent upgrade for efficiency-critical designs like:
Higher-current DC-DC converters.
More demanding motor drives or solenoid controls.
Power switches where reduced heat generation is important.
Comparative Analysis: BSN20BKR (N-channel) vs. VB162K
This comparison shifts to low-power, signal-level MOSFETs where small size and basic switching efficiency are paramount.
Analysis of the Original Model (BSN20BKR) Core:
This is a 60V N-channel MOSFET from Nexperia in a compact SOT-23 package. It is designed for signal switching, level shifting, and driving very small loads. Its core parameters are a 330mA continuous drain current, an on-resistance of 2.8Ω at 10V gate drive, and a power dissipation of 1.672W. It offers a reliable, space-saving solution for low-current circuits.
Compatibility and Differences of the Domestic Alternative (VB162K):
VBsemi's VB162K is a direct SOT-23-3 pin-to-pin alternative. Its parameters are highly comparable: a 60V voltage rating, a 0.3A (300mA) continuous current, and an on-resistance of 2.8kΩ (2800mΩ) at 10V. The slightly different RDS(on) specification (2.8Ω vs. 2.8kΩ in the provided data appears to be a unit discrepancy; typical SOT-23 parts for this current range are in the Ohm range) requires careful cross-checking with datasheets, but the package and basic ratings indicate direct functional replacement potential.
Key Application Areas:
Original Model BSN20BKR: Perfect for low-power signal interfacing and control. Typical applications include:
Load switching for sensors, LEDs, or other micro-peripherals.
Level translation in communication interfaces.
Input/output port protection and driving in microcontroller circuits.
Alternative Model VB162K: Serves the same application space—signal-level switching and isolation in space-constrained designs like:
Portable and battery-powered IoT devices.
Consumer electronics control circuits.
General-purpose low-side switches.
Conclusion
This analysis reveals two distinct substitution strategies:
For medium-power switching (BUK72150-55A,118), the domestic alternative VBE1695 presents a compelling performance-enhanced option. With a lower on-resistance (73mΩ vs. 127mΩ) and higher current rating (18A vs. 11A), it can directly replace the original in DPAK/TO-252 footprints while offering potential for higher efficiency and lower thermal stress in upgrades or new designs.
For signal-level switching (BSN20BKR), the domestic alternative VB162K appears as a direct functional replacement in the ubiquitous SOT-23 package. With matching voltage (60V) and similar current ratings (~0.3A), it provides a viable alternative for basic on/off control of small loads, supporting supply chain diversification without compromising board layout.
The core takeaway remains: selection is about precise requirement matching. In the context of supply chain diversification, domestic alternatives like VBE1695 and VB162K not only provide reliable backup options but can also offer performance advantages or cost benefits, giving engineers greater flexibility and resilience in design trade-offs.