Introduction
This application note details critical Printed Circuit Board (PCB) design considerations for maximizing the performance of GaN power switches when driven by the onsemi NCP51820. Achieving the full benefits of high-voltage, high-frequency switching with fast dV/dt rates requires a meticulously designed PCB. This document highlights key PCB layout strategies, component placement, and routing techniques essential for successful GaN-based half-bridge power topologies.
Key Design Considerations
- Multi-layer PCB Design: Emphasizes the necessity of multi-layer PCBs with proper ground/return planes for high-frequency, high-voltage applications.
- Component Placement: Advises placing noise-sensitive components, such as bypass capacitors, close to the NCP51820 and GaNFETs.
- Gate Drive Routing: Stresses the importance of short, direct gate drive paths and the use of isolated return planes to mitigate parasitic inductance and noise.
- Kelvin Connections: Explains the critical role of Kelvin connections for isolating gate drive return current from high-current switch-node paths.
- Grounding Strategy: Details the separation and connection points for Signal Ground (SGND) and Power Ground (PGND) to prevent noise injection.
About onsemi
onsemi is a leading provider of intelligent power and sensing technologies that are accelerating the automotive and aerospace megatrends. onsemi's technology helps engineers solve their design challenges in automotive, industrial, cloud, mobile, communications, medical, and consumer markets. Learn more at www.onsemi.com.
