Shared Case Electrode for Implantable Device Power Noise Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Implantable medical devices (IMDs) face challenges in minimizing volume while maintaining efficient energy supply and sensing pathways, often requiring multiple feedthroughs that increase manufacturing costs and can corrupt sensing signals with energy current.
Innovation Solution
The IMD electrically couples the negative battery terminal to the case, sharing a portion of the case for both energy supply and sensing pathways, using a single feedthrough assembly and a switch to selectively isolate the energy supply, allowing for reduced volume and cost while minimizing signal corruption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple feedthroughs are used to electrically isolate the battery from the device case, then electrical isolation is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent combines multiple feedthrough functions into a single feedthrough assembly. The battery housing serves dual purposes: as both the battery container and as an electrical connection element (electrode) for sensing. This merging eliminates the need for separate feedthroughs for each battery terminal, reducing device complexity while maintaining electrical isolation through the single integrated feedthrough assembly.
Solution Approach 2:
The battery housing is given multiple functions: it serves as the battery container, as an electrode for sensing physiological parameters, and as part of the electrical connection pathway. This multi-functionality reduces the number of separate components needed, particularly eliminating the need for multiple feedthroughs, thereby reducing device complexity and manufacturing cost.
2Volume of stationary object
If the battery housing is used as part of the device case to reduce volume, then device volume is reduced, but signal corruption from energy current increases
Solution Approach 1:
The patent segments the electrical pathways into distinct routes: the energy supply current flows through the battery housing to the feedthrough assembly, while the sensing signal flows through separate sensing electrodes and circuitry. This segmentation allows the battery housing to serve as both structural element and electrical connection without the energy current directly interfering with the sensing signals, thus reducing signal corruption while maintaining compact volume.
Solution Approach 2:
The feedthrough assembly acts as an intermediary element between the battery housing and the device circuitry. It provides the necessary electrical isolation and signal conditioning, allowing the battery housing to be part of the device case while preventing direct coupling of energy current into the sensing pathways, thereby reducing signal corruption.
3Ease of manufacture
If a single feedthrough is used to reduce manufacturing cost, then manufacturing cost is reduced, but electrical isolation and signal quality may deteriorate
Solution Approach 1:
The patent merges the functions of multiple feedthroughs into a single integrated feedthrough assembly that handles both battery terminals. This consolidation reduces manufacturing cost by eliminating redundant components and assembly steps while maintaining electrical isolation through the integrated design of the feedthrough assembly and its connection to the battery housing.
Solution Approach 2:
The single feedthrough assembly is designed to perform multiple functions: providing electrical isolation, establishing electrical connections for both battery terminals, and serving as part of the sensing pathway. This multi-functionality allows a single component to replace what would traditionally require multiple feedthroughs, reducing manufacturing cost while maintaining reliability.
Data Source
AI summary
A medical device includes a case and a core assembly. The core assembly includes operational circuitry enclosed within a core assembly housing. The medical device also includes a battery assembly, which includes a battery enclosed within a battery housing. The case includes the core assembly housing and the battery housing. A first electrode is coupled to, and electrically isolated from, the case; and a second electrode is electrically coupled to the case. The second electrode is electrically coupled to the operational circuitry via a sensing pathway that includes a portion of the case. The battery is electrically coupled to the operational circuitry via an energy supply pathway that includes the portion of the case.