In high-voltage power designs, selecting the right MOSFET involves balancing voltage rating, current capability, switching performance, and package size. This analysis uses two established MOSFETs—STQ1HN60K3-AP (low-current, high-voltage) and STL26N65DM2 (medium-power, high-voltage)—as benchmarks, and evaluates their domestic alternatives, VBR165R01 and VBQE165R20S. By comparing key parameters and design focus, we provide a clear selection guide for your next high-voltage switching solution.
Comparative Analysis: STQ1HN60K3-AP (N-channel) vs. VBR165R01
Analysis of the Original Model (STQ1HN60K3-AP) Core:
This is a 600V N-channel MOSFET from STMicroelectronics in a compact TO-92-3 package. It is designed for low-current, high-voltage applications where simplicity and cost-effectiveness are key. Its core advantages are a high drain-source voltage (600V) and a continuous drain current of 400mA, with a power dissipation of 3W. It suits basic off-line switching or auxiliary power functions where minimal drive complexity is needed.
Compatibility and Differences of the Domestic Alternative (VBR165R01):
VBsemi’s VBR165R01 is a direct pin-to-pin compatible alternative in a TO92 package. The main differences are in electrical parameters: VBR165R01 offers a higher voltage rating (650V) and a significantly higher continuous current (1A). However, its on-resistance is higher at 6667mΩ @10V compared to the typical performance profile of the original.
Key Application Areas:
Original Model STQ1HN60K3-AP: Ideal for low-power, high-voltage switching tasks such as:
Auxiliary power supplies in appliances or industrial controls.
Snubber circuits or low-current offline switchers.
LED driver stages requiring simple high-side switching.
Alternative Model VBR165R01: Better suited for applications needing higher voltage margin (650V) and slightly higher current capability (up to 1A), but where higher on-resistance can be tolerated, such as in certain protection circuits or low-frequency switches.
Comparative Analysis: STL26N65DM2 (N-channel) vs. VBQE165R20S
This comparison focuses on medium-power, high-efficiency applications. The original model emphasizes a balance of high voltage, moderate current, and low switching loss.
Analysis of the Original Model (STL26N65DM2) Core:
This 650V N-channel MOSFET from ST uses the PowerVDFN-8 (PowerFLAT 8x8 HV) package. Its design core is high-voltage power conversion with good thermal performance. Key advantages include a 650V rating, 20A continuous current, and a low typical on-resistance of 0.182Ω (206mΩ @10V max). It features ST’s MDmesh DM2 technology for optimized switching performance in hard-switching topologies.
Compatibility and Differences of the Domestic Alternative (VBQE165R20S):
VBsemi’s VBQE165R20S is a performance-enhanced alternative in a DFN8x8 package. It matches the 650V rating and 20A current but offers a significantly lower on-resistance of 160mΩ @10V. This reduction in RDS(on) translates to lower conduction losses and potentially higher efficiency.
Key Application Areas:
Original Model STL26N65DM2: Excellent for medium-power, high-voltage applications demanding good switching performance and thermal management, such as:
Switch-mode power supplies (SMPS) for servers, telecom, or industrial equipment.
Power factor correction (PFC) stages.
Motor drives and inverters operating from high-voltage DC buses.
Alternative Model VBQE165R20S: Ideal for upgrade scenarios where lower conduction loss is critical. It suits high-efficiency versions of the above applications, like high-density SMPS or motor drives where reduced heat generation is a priority.
Conclusion:
This analysis reveals two distinct selection paths for high-voltage designs:
For low-current, cost-sensitive high-voltage switching, the original STQ1HN60K3-AP, with its 600V rating and 400mA capability in a simple TO-92 package, remains a solid choice for basic auxiliary functions. Its domestic alternative VBR165R01 offers higher voltage (650V) and current (1A) but with higher on-resistance, making it suitable for designs prioritizing voltage headroom over ultimate conduction loss.
For medium-power, high-efficiency high-voltage applications, the original STL26N65DM2 provides a reliable balance of 650V, 20A, and good switching characteristics in a thermally efficient package. The domestic alternative VBQE165R20S presents a compelling "performance-enhanced" option, significantly lowering on-resistance to 160mΩ for reduced losses in demanding power conversion stages.
The core takeaway is that selection depends on precise requirement matching. Domestic alternatives like VBR165R01 and VBQE165R20S offer not only supply chain resilience but also opportunities for parameter-specific upgrades, giving engineers greater flexibility in design trade-offs and cost optimization for high-voltage circuits.