High-Frequency Module Layout for Heat Dissipation and Filter Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high frequency modules face challenges in reducing size while maintaining heat-dissipating properties and stable operation of power amplifiers, as thermal vias occupy space and can cause electromagnetic coupling between filters, leading to reduced isolation and potential oscillation.
Innovation Solution
A high frequency module design featuring a multilayered substrate with power amplifier IC, first and second filters disposed directly below the IC, and coupling-reducing ground vias that double as thermal vias to prevent electromagnetic coupling and maintain heat dissipation, using an interdigital λ/4 resonator for the first filter to reduce via holes and enhance heat transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If thermal vias are disposed directly below the power amplifier IC to dissipate heat, then heat dissipation is improved, but the module size cannot be reduced because thermal vias occupy space and prevent filter placement
Solution Approach 1:
The ground vias of the first filter are made to serve dual purposes: as ground connections for the filter circuit and as thermal vias for heat dissipation from the power amplifier IC. This multi-functionality allows the same structural elements to address both electromagnetic grounding and thermal management needs, eliminating the need for separate thermal via structures.
Solution Approach 2:
The invention merges the ground via structure of the first filter with the thermal via structure required for the power amplifier IC. By combining these two previously separate functions into a single integrated structure, the module achieves both effective heat dissipation and compact size without requiring additional space for dedicated thermal vias.
2Volume of moving object
If the first and second filters are disposed close to the power amplifier IC to reduce module size, then module size is reduced, but electromagnetic coupling occurs between filters causing reduced isolation and potential oscillation
Solution Approach 1:
The first filter acts as an intermediary component that provides electromagnetic isolation between the power amplifier IC and the second filter. By positioning the first filter between these components and using its ground vias for both grounding and heat dissipation, the design achieves effective isolation to prevent oscillation while maintaining compact dimensions.
3Temperature
If thermal vias are used for heat dissipation, then heat dissipation is improved, but electromagnetic coupling between filters is caused leading to reduced isolation
Solution Approach 1:
The ground vias of the first filter are designed to simultaneously provide electromagnetic grounding for filter isolation and serve as thermal conduction paths for heat dissipation. This dual-function design eliminates the need for separate thermal vias that would cause electromagnetic coupling, as the filter's own ground structure performs both functions effectively.
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
This design allows for a smaller, high-performance high frequency module with stable power amplifier operation and effective heat dissipation, preventing feedback and oscillation by reducing electromagnetic coupling between filters.
Implementation Method 1
coupling-reducing ground vias 21 disposed between the first filter 12 and the second filter 13, the coupling-reducing ground vias 21 double as power amplifier thermal vias 22
Implementation Method 2
coupling-reducing ground vias disposed between the first filter and the second filter, preventing feedback and oscillation by reducing electromagnetic coupling between filters
Data Source
AI summary
The present invention is provided with a high frequency module comprising a multilayered substrate, a power amplifier IC mounted on the upper surface of the multilayered substrate, first and second filters disposed substantially directly below the power amplifier IC in an inner layer of the multilayered substrate, and coupling-reducing ground vias disposed between the first filter and the second filter. At least the first filter is disposed substantially directly below the power amplifier IC. The coupling-reducing ground vias double as thermal vias for dissipating heat generated by the power amplifier IC.