Transistor Module Assembly with Longitudinal Bus Bars
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional power distribution systems face limitations due to high interconnect resistance and impedance in arrays using multiple power MOSFETs, which restricts power capacity and heat dissipation.
Innovation Solution
A transistor module assembly featuring longitudinally extending load and feed bus bars with transistor packages connected to them, along with a printed wiring board, provides low impedance connections and improved heat dissipation through transverse tabs and legs, allowing for higher current arrays and efficient assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple power MOSFETs are arranged in an array using conventional PWB interconnects, then the array can provide power distribution capability, but the interconnect resistance and impedance increase, limiting the power capacity
Solution Approach 1:
The invention divides the interconnect structure into separate feed bus bar and load bus bar components that are longitudinally extending and parallel to each other. This segmentation allows each bus bar to be optimized independently for low impedance and low resistance, respectively, while maintaining the necessary electrical connections between multiple MOSFETs in the array.
Solution Approach 2:
The invention transitions from conventional two-dimensional PWB trace interconnections to a three-dimensional bus bar structure that extends longitudinally alongside the MOSFET array. This dimensional change enables significantly lower impedance and resistance paths for current flow, as the bus bars provide direct electrical connection without relying on limited copper trace areas on a PWB.
2Power
If multiple power MOSFETs are arranged in an array using conventional PWB interconnects, then the array can provide power distribution capability, but heat removal becomes difficult
Solution Approach 1:
The invention merges the electrical interconnect function with the thermal management function by making the feed bus bar and load bus bar also serve as heat dissipation pathways. The bus bars are thermally coupled to the MOSFET packages and extend longitudinally, providing low thermal resistance paths for heat removal from the power devices.
3Reliability
If bus bars are made longitudinally extending and parallel to reduce impedance, then electrical connection is improved, but the structural complexity increases
Solution Approach 1:
The bus bars are designed to perform multiple functions simultaneously: they provide low-impedance electrical interconnection between MOSFETs, serve as current carrying conductors, and act as heat dissipation pathways. This multi-functionality reduces the need for separate components and simplifies the overall structure despite the longitudinally extending parallel configuration.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution reduces electrical impedance and enhances heat dissipation, enabling higher power handling and modular assembly for high-power applications with reduced heat generation.
Implementation Method 1
The drain surface is operatively connected to the feed bus bar for receiving current therefrom
Implementation Method 2
The source lead is operatively connected to the load bus bar for dissipating current from the transistor package to the load bus bar
Implementation Method 3
it can be difficult to remove heat from the array
Data Source
AI summary
A transistor module assembly includes a longitudinally extending load bus bar, a longitudinally extending feed bus bar parallel to the load bus bar, and at least one transistor package operatively connected to the load and feed bus bars. The transistor package includes a drain surface and a source lead. The drain surface is operatively connected to the feed bus bar for receiving current therefrom. The source lead is operatively connected to the load bus bar for dissipating current from the transistor package to the load bus bar.