In modern power design, achieving optimal efficiency and space utilization in low-voltage, compact applications is a key challenge. Selecting the right P-Channel MOSFET involves balancing on-resistance, current capability, package size, and cost. This article takes two representative P-Channel MOSFETs from DIODES—DMP3160LQ-7 (SOT-23-3) and DMP3068LVT-13 (TSOT-26)—as benchmarks, analyzes their design focus and application scenarios, and evaluates two domestic alternative solutions: VB2355 and VB8338 from VBsemi. By comparing their parameter differences and performance orientations, we provide a clear selection guide to help you find the most suitable power switching solution for your next compact design.
Comparative Analysis: DMP3160LQ-7 (P-Channel) vs. VB2355
Analysis of the Original Model (DMP3160LQ-7) Core:
This is a 30V P-Channel MOSFET from DIODES in a compact SOT-23-3 package. It is designed to minimize conduction loss while maintaining good switching performance for efficient power management. Its key parameters include a continuous drain current (Id) of -2.7A and an on-resistance (RDS(on)) of 97mΩ at 10V gate drive (165mΩ at 4.5V). This makes it suitable for applications where moderate current handling and low on-resistance are needed in a minimal footprint.
Compatibility and Differences of the Domestic Alternative (VB2355):
VBsemi’s VB2355 is also offered in an SOT-23-3 package and serves as a direct pin-to-pin compatible alternative. The key differences are in electrical performance: VB2355 features a significantly lower on-resistance—46mΩ at 10V and 54mΩ at 4.5V—which is roughly half that of the original part. It also supports a higher continuous current of -5.6A, providing better current handling and lower conduction losses.
Key Application Areas:
- Original Model DMP3160LQ-7: Ideal for space-constrained, efficiency-oriented applications such as load switching, power distribution, or DC-DC conversion in portable devices, IoT modules, or battery management systems where 2-3A current and 30V rating are sufficient.
- Alternative Model VB2355: Better suited for upgrades or new designs requiring higher efficiency and current capacity within the same package. Its lower RDS(on) and higher current rating make it excellent for more demanding power paths, higher-efficiency converters, or applications where thermal performance and power loss reduction are critical.
Comparative Analysis: DMP3068LVT-13 (P-Channel) vs. VB8338
Analysis of the Original Model (DMP3068LVT-13) Core:
This 30V P-Channel MOSFET from DIODES comes in a TSOT-26 package, offering a good balance between size and performance. It is engineered for low on-resistance and efficient switching, with specifications including a continuous drain current of -2.8A and an RDS(on) of 105mΩ at 4.5V gate drive. Its compact form factor and reliable performance make it a popular choice for advanced power management circuits.
Compatibility and Differences of the Domestic Alternative (VB8338):
VBsemi’s VB8338 is provided in an SOT-23-6 package. While not a direct pin-to-pin match for the TSOT-26, it serves as a functional alternative with enhanced electrical characteristics. VB8338 offers a lower on-resistance—49mΩ at 10V and 54mΩ at 4.5V—and supports a higher continuous current of -4.8A. This represents a substantial improvement in conduction performance and current capability over the original.
Key Application Areas:
- Original Model DMP3068LVT-13: Well-suited for compact power management designs such as battery protection circuits, load switches, or low-side switches in DC-DC converters where a small TSOT-26 package and 30V/2.8A capability meet the requirements.
- Alternative Model VB8338: An excellent choice when design flexibility allows for a different package (SOT-23-6) and where higher performance is desired. Its lower RDS(on) and higher current rating make it suitable for more efficient power switching, motor drive circuits, or applications demanding better thermal behavior and lower losses.
Summary
This comparison reveals two distinct selection pathways:
- For ultra-compact SOT-23-3 P-Channel applications, the original DMP3160LQ-7 provides a solid balance of size and performance. Its domestic alternative VB2355 delivers significant performance gains with much lower on-resistance and higher current capacity, making it a superior choice for efficiency-critical upgrades or new designs.
- For designs using the TSOT-26 package, the original DMP3068LVT-13 offers reliable performance in a tiny footprint. The alternative VB8338, though in a different package, provides enhanced electrical characteristics—lower RDS(on) and higher current—suitable for engineers who can adapt the layout and seek higher power efficiency.
The core insight is that selection depends on precise requirement matching. In the context of supply chain diversification, domestic alternatives like VB2355 and VB8338 not only offer viable backups but also provide performance advantages in key parameters, giving engineers greater flexibility and resilience in design trade-offs and cost control. Understanding each device’s design philosophy and parameter implications is essential to maximize its value in the circuit.