Power Semiconductor Module Frame Protrusions to Reduce PCB Strain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing power semiconductor module assembly techniques result in high strain on circuit boards due to height tolerance issues, which can damage sensitive components, and require costly metal screws for fixation, increasing the overall size and cost of the assembly.
Innovation Solution
The use of an electrically insulative frame with vertically aligned protrusions for attaching both the circuit board and metal base plate, eliminating gaps and reducing strain on the circuit board, while allowing for easier assembly and reducing the need for metal fasteners.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If metal screws are used to attach the circuit board and base plate, then the fixing strength is improved, but the overall size and cost of the assembly increases
Solution Approach 1:
The patent extracts the fastening function from metal screws and transfers it to integrated protrusions formed directly on the frame. This eliminates the need for separate metal fasteners, reducing assembly size and cost while maintaining fixing strength through the protrusions' mechanical engagement with the circuit board and base plate
Solution Approach 2:
The patent merges the fastening function into the frame structure itself by forming protrusions as integral parts of the frame. This combines the support and fixation functions into a single component, eliminating the need for separate metal screws and reducing the overall assembly size
2Reliability
If metal screws are used for attachment, then the fixing reliability is improved, but the clearance and creepage distance requirements increase the overall size
Solution Approach 1:
The patent introduces electrically insulating protrusions as an intermediary element between the frame and the attachment components (circuit board and base plate). These protrusions provide mechanical fixing reliability while being electrically insulating, thereby eliminating the need for additional clearance and creepage distances that would be required if metal screws were used
3Manufacturing precision
If vertically aligned fixing positions are used for PCB and base plate, then the manufacturing precision is improved, but the PCB strain increases due to height tolerance
Solution Approach 1:
The patent incorporates height tolerance compensation directly into the protrusion design. The protrusions are designed with dimensions and material properties that allow them to absorb height tolerance variations before they are transmitted to the PCB, thereby cushioning the PCB against excessive strain while maintaining vertically aligned fixing positions for manufacturing precision
Data Source
AI summary
A power semiconductor module includes: an electrically insulative frame having opposite first and second mounting sides, and a border that defines a periphery of the electrically insulative frame; a first substrate seated in the electrically insulative frame; a plurality of power semiconductor dies attached to the first substrate; a plurality of signal pins attached to the first substrate and electrically connected to the power semiconductor dies; a plurality of busbars attached to the first substrate and extending through the border of the electrically insulative frame; a plurality of fixing positions at the first mounting side of the electrically insulative frame; and a plurality of electrically insulative protrusions jutting out from the second mounting side of the electrically insulative frame, wherein the protrusions are vertically aligned with the fixing positions. Methods of producing the power semiconductor module and power electronic assemblies that incorporate the power semiconductor module are also described.