In modern power design, achieving high current handling and low conduction loss in a compact footprint is a critical challenge. This article takes two high-performance N-channel MOSFETs from onsemi—NTMFS5C673NLT1G and NTMFS5C628NT1G—as benchmarks, analyzing their design focus and application scenarios, while evaluating their domestic alternatives, VBQA1606 and VBQA1603 from VBsemi. By comparing key parameters and performance orientations, we provide a clear selection guide to help identify the optimal power switching solution for your next high-density design.
Comparative Analysis: NTMFS5C673NLT1G vs. VBQA1606
Analysis of the Original Model (NTMFS5C673NLT1G) Core:
This is a 60V, 50A N-channel MOSFET from onsemi in a DFN-5 (4.9x5.9) package. Its design emphasizes balanced performance for medium-to-high current applications. Key advantages include a low on-resistance of 9.2mΩ at 10V gate drive and a continuous drain current rating of 50A, supported by a 46W power dissipation capability. It offers reliable switching with robust thermal performance in a small form factor.
Compatibility and Differences of the Domestic Alternative (VBQA1606):
VBsemi's VBQA1606 is offered in a DFN8 (5x6) package and serves as a pin-to-pin compatible alternative. It shows enhanced performance in key areas: a lower on-resistance of 6mΩ at 10V and a higher continuous current rating of 80A. The gate threshold voltage is compatible at 2.5V, making it a suitable drop-in replacement with improved conduction characteristics.
Key Application Areas:
Original Model NTMFS5C673NLT1G: Ideal for compact 48V-60V systems requiring up to 50A current, such as:
- DC-DC converters in telecom/server power supplies.
- Motor drives for industrial tools or e-mobility.
- Power distribution switches in space-constrained layouts.
Alternative Model VBQA1606: Better suited for applications demanding lower conduction loss and higher current capability (up to 80A), such as upgraded power stages or high-efficiency synchronous rectification where thermal performance is critical.
Comparative Analysis: NTMFS5C628NT1G vs. VBQA1603
Analysis of the Original Model (NTMFS5C628NT1G) Core:
This onsemi MOSFET is designed for ultra-high current in a miniaturized DFN-5 (5.9x4.9) package. It features a remarkable 150A continuous drain current at 60V, with an exceptionally low on-resistance of 2.3mΩ at 10V. Its core advantages include minimal conduction loss, low gate charge for fast switching, and a small footprint ideal for high-density designs.
Compatibility and Differences of the Domestic Alternative (VBQA1603):
VBQA1603 from VBsemi, also in a DFN8 (5x6) package, provides a direct alternative with competitive specs. It offers a continuous current of 100A and an even lower on-resistance of 3mΩ at 10V (5mΩ at 4.5V). While its current rating is lower than the original, its ultra-low RDS(on) ensures high efficiency in high-current paths.
Key Application Areas:
Original Model NTMFS5C628NT1G: Excels in applications requiring extreme current density and minimal loss:
- High-current POL (point-of-load) converters for servers/GPUs.
- Battery management systems (BMS) in electric vehicles or energy storage.
- Heavy-duty motor controllers and inverter modules.
Alternative Model VBQA1603: A strong choice for designs prioritizing very low RDS(on) and high efficiency at currents up to 100A, suitable for compact high-power DC-DC conversion, advanced motor drives, or as an enhancement in existing 60V power platforms.
Conclusion:
The comparison highlights two distinct selection pathways:
For balanced medium-high current applications, the original NTMFS5C673NLT1G offers proven 50A capability with 9.2mΩ RDS(on), while its alternative VBQA1606 provides upgraded performance with 80A and 6mΩ RDS(on), ideal for efficiency-focused upgrades.
For ultra-high current density needs, the original NTMFS5C628NT1G delivers an unmatched 150A with 2.3mΩ RDS(on) in a tiny package. The alternative VBQA1603, with 100A and 3mΩ RDS(on), presents a compelling domestic option for designs where extreme low resistance and compact size are critical.
Ultimately, selection depends on precise requirement matching: current handling, loss minimization, and footprint constraints. Domestic alternatives like VBQA1606 and VBQA1603 not only offer supply chain resilience but also competitive or enhanced parameters, giving engineers greater flexibility in optimizing performance, cost, and reliability.