PQFN GaN FETs Paralleling PCB Application Note
■Trasphorm's PQFN (Power Quad Flatpack No Lead) package incorporates a DPC (Direct Plated Cu) substrate and a Cu lead frame encapsulated in a green molding compound for bottom electrical connection and thermal contact to printed circuit board. It provides high lateral electrical isolation and excellent heat dissipation in applications similar to a D2Pak but in a thinner form factor [1]. The new generation 650V/70mΩPQFN packaging devices TP65H070LxG have been released, where the “X” is “S”or“D”meaning source tab or drain tab, respectively. For the traditional Si-MOSFET, there is only drain metal tab PQFN device as the bottom of the die is always drain terminal. GaN FETs have much higher dv/dt switching speed. For the bridge applications, if both high side and low side devices are drain tab ones and connected to the large copper PCB for heat dissipation, the low side drain tab will be the switching node.High dv/dt potential change on this copper area will behave like an antenna to radiate high frequency noise, or high the dv/dt will couple through the capacitance between PCB and heatsink or other signal layers to generate common mode noise current, resulting in Electromagnetic compatibility (EMC) issue or circuit malfulction. In order to solve this issue, it is better to choose source tab device for low side and drain tab device for high side. As a result, the tabs will connect to either power ground or high voltage DC rail where there are no high dv/dt switching, and the large copper plates helps build up decoupling capacitance to suppress the voltage spikes.
■The generation III devices provide 4V threshold gate voltage and better switching performance. For achieving higher power requirement, 2x PQFN in parallel is necessary. In this application note, the combination with LDG FETs on high side and LSG FETs on low side in paralleling will be discussed.
|
|
|
|
Application note & Design Guide |
|
|
|
|
Please see the document for details |
|
|
|
|
|
|
|
|
PQFN |
|
|
English Chinese Chinese and English Japanese |
|
|
November 06, 2018 |
|
|
|
|
|
an0011.1 |
|
|
4 MB |
- +1 Like
- Add to Favorites
Recommend
All reproduced articles on this site are for the purpose of conveying more information and clearly indicate the source. If media or individuals who do not want to be reproduced can contact us, which will be deleted.
Integrated Circuits
Discrete Components
Connectors & Structural Components
Assembly UnitModules & Accessories
Power Supplies & Power Modules
Electronic Materials
Instrumentation & Test Kit
Electrical Tools & Materials
Mechatronics
Processing & Customization
