Driven by the growing demand for robust and efficient power management in automotive and industrial applications, domestic substitution of critical power semiconductors has shifted from an alternative to a strategic necessity. Facing requirements for high reliability, high current capability, and low loss in medium-voltage applications, identifying a high-performance, quality-assured, and supply-stable local alternative has become essential for OEMs and system designers. When considering the widely used 75V N-channel MOSFET from Nexperia—the BUK7Y18-75B,115—the VBED1806 from VBsemi stands out as a powerful replacement. It not only matches the functional footprint but also delivers significant performance enhancements based on advanced Trench technology, representing a shift from “direct substitution” to “performance upgrade.”
I. Parameter Comparison and Performance Enhancement: Key Benefits of Advanced Trench Technology
The BUK7Y18-75B,115 has been adopted in applications such as automotive motor drives, DC-DC converters, and load switching due to its 75V voltage rating, 49A continuous current, and 13.8mΩ typical on-resistance. However, as systems pursue higher efficiency and power density, lower conduction loss and improved thermal performance become critical.
1. While maintaining compatibility in package (LFPAK56) and circuit interface, the VBED1806 achieves notable improvements in electrical parameters through optimized Trench MOSFET design:
- Higher Voltage Rating & Current Capability: With VDS increased to 80V and continuous drain current rated at 90A, the device offers greater design margin and reliability in demanding conditions.
- Significantly Reduced On-Resistance: At VGS=10V, RDS(on) is as low as 6mΩ, less than half of the reference device. According to Pcond = I_D²·RDS(on), this dramatically cuts conduction losses at high load currents, improving efficiency and thermal performance.
- Enhanced Drive Compatibility: With a standard Vth of 1.4V and VGS tolerance of ±20V, the device ensures robust gate driving and compatibility with common controller ICs.
2. Improved Switching Performance: The Trench technology enables lower gate charge and capacitance, resulting in faster switching and reduced dynamic losses, beneficial for high-frequency power conversion.
3. Thermal and SOA Robustness: The design offers better thermal dissipation and safe operating area, supporting stable operation under high current and temperature conditions.
II. Application Scenarios: Seamless Replacement with System-Level Benefits
The VBED1806 can directly replace the BUK7Y18-75B,115 in existing designs while enabling system improvements:
1. Automotive Motor Drives (e.g., fan, pump, window control)
Lower RDS(on) reduces heat generation, enhancing reliability in under-hood environments and allowing for possible downsizing of heatsinks.
2. DC-DC Converters (12V/24V to lower voltage)
Higher efficiency across load range improves power conversion performance and supports higher power density designs.
3. Load Switches & Power Distribution
The high current rating and low loss make it ideal for high-side switches in power distribution boxes, reducing voltage drop and improving system efficiency.
4. Industrial Power Supplies & Motor Controls
Suitable for low-voltage motor drives, UPS, and SMPS, where low conduction loss and high switching reliability are valued.
III. Beyond Specifications: Reliability, Supply Assurance, and Lifecycle Value
Choosing VBED1806 is both a technical and strategic decision:
1. Domestic Supply Chain Security
VBsemi ensures full control from chip to package, providing stable supply, shorter lead times, and reduced geopolitical and logistics risks.
2. Cost-Effectiveness
Competitive pricing and local support help reduce BOM costs and improve end-product value proposition.
3. Local Technical Support
From simulation to testing and failure analysis, VBsemi offers responsive engineering support, accelerating design cycles and issue resolution.
IV. Replacement Guidance
For designs currently using or planning to use BUK7Y18-75B,115, the following steps are recommended:
1. Electrical Validation
Compare switching waveforms, losses, and thermal performance under same operating conditions. Optimize gate drive if needed to leverage faster switching of VBED1806.
2. Thermal Re-assessment
Due to lower losses, thermal design may be relaxed, potentially reducing heatsink size or cost.
3. Reliability & System Testing
Conduct rigorous electrical, thermal, and environmental tests before final system integration to ensure long-term reliability.
Moving Forward with a High-Performance, Locally Sourced Power Solution
The VBsemi VBED1806 is not just a pin-to-pin alternative—it is a superior MOSFET solution that enhances system efficiency, current handling, and thermal performance for medium-voltage automotive and industrial applications. With better electrical characteristics, supply chain stability, and local support, it represents a smart upgrade for designers pursuing higher performance and supply chain autonomy.
In an era where reliability and localization go hand in hand, adopting VBED1806 is a forward-looking choice for next-generation power designs. We recommend this solution and look forward to supporting your success in power electronics innovation.