Elastic Wave Filter Layout With Shared Ground Terminals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing elastic wave devices face challenges in reducing size while maintaining desired filter characteristics, as the grounding state of each elastic wave filter is crucial and individual ground connection terminals are necessary, making it difficult to minimize the device's size.
Innovation Solution
The elastic wave device configuration includes a piezoelectric substrate with multiple filter electrodes and terminal electrodes, where a ground terminal electrode is shared between adjacent filter electrodes, reducing the number of ground terminals and optimizing their placement to enhance grounding and filter characteristics, thereby allowing for size reduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If individual ground connection terminals are provided for each elastic wave filter, then desired filter characteristics are achieved, but the device size increases
Solution Approach 1:
The patent combines multiple ground connection terminals into a single shared ground terminal that serves multiple elastic wave filters simultaneously. This merging approach reduces the total number of ground terminals required, thereby decreasing the device area while maintaining proper grounding for all filters.
Solution Approach 2:
The ground terminal is designed to serve multiple functions by providing grounding for multiple different elastic wave filters through a single terminal. This multi-functional design allows one ground terminal to replace what would traditionally require multiple separate terminals.
2Reliability
If multiple ground connection terminals are provided, then grounding state is satisfied, but space on piezoelectric substrate is consumed
Solution Approach 1:
Multiple ground connection functions are merged into a single ground terminal structure, eliminating the need for multiple separate terminals on the piezoelectric substrate. This reduces substrate space consumption while maintaining adequate grounding state.
3Area of stationary object
If resonator electrodes are formed on one piezoelectric substrate to reduce size, then device compactness improves, but desired filter characteristics become difficult to achieve
Solution Approach 1:
The patent merges multiple filter structures onto a single piezoelectric substrate while implementing a shared ground terminal configuration. This allows compact integration without sacrificing filter characteristics, as the shared grounding approach maintains proper electrical reference for all filters.
Solution Approach 2:
The patent arranges multiple resonator electrodes and filters in a planar configuration on the substrate surface, utilizing two-dimensional space efficiently. The shared ground terminal is positioned to serve multiple filters simultaneously, optimizing the spatial arrangement.
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 configuration achieves good filter characteristics for multiple elastic wave filters while minimizing the device's size by stabilizing the grounding and reducing the area required for ground terminals.
Implementation Method 1
a piezoelectric substrate and an electrode pattern that define elastic wave filters provided on a surface of the piezoelectric substrate
Implementation Method 2
an electrode pattern that define elastic wave filters provided on a surface of the piezoelectric substrate
Data Source
AI summary
An elastic wave device includes a piezoelectric substrate, filter electrodes, input terminal electrodes, output terminal electrodes, and ground terminal electrodes. The filter electrodes are disposed along a first direction. The ground terminal electrodes corresponding to the filter electrodes are respectively disposed between adjacent filter electrodes, and are common to the adjacent filter electrodes.