Ceramic Capacitive Interface with Shielding for Galvanic Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ceramic hermetic packages fail to effectively provide galvanic isolation between semiconductor dies with different ground potentials while allowing for efficient information transmission, leading to potential current flow and interference issues.
Innovation Solution
A semiconductor package design featuring a ceramic header with capacitive interfaces and shielding elements, where capacitive elements with tunable capacitance values and shielding elements provide isolation and communication between semiconductor dies, ensuring independent ground planes and preventing direct current flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If galvanic isolation is implemented using capacitive barriers between semiconductor dies, then current flow between different ground potentials is prevented, but information transmission efficiency is reduced
Solution Approach 1:
The capacitive interface is segmented into multiple capacitive elements (first capacitive element, second capacitive element, etc.) arranged in parallel between the semiconductor dies. This segmentation allows information to be transmitted through multiple capacitive paths simultaneously, improving transmission efficiency while maintaining galvanic isolation through the capacitive barrier.
Solution Approach 2:
The capacitive interface acts as an intermediary between the first and second semiconductor dies, allowing information transmission while blocking direct current flow. The capacitive elements serve as mediators that enable signal coupling between different ground potentials without creating a direct conductive path.
2Object-affected harmful factors
If shielding elements are added to the capacitive interface, then electromagnetic interference is reduced, but device complexity increases
Solution Approach 1:
The shielding elements are merged with the capacitive interface structure, forming an integrated assembly where shielding elements are positioned adjacent to and coupled with the capacitive elements. This merging approach provides electromagnetic shielding without requiring completely separate shielding structures, thereby limiting the increase in device complexity.
3Reliability
If multiple capacitive elements are used for communication, then information transmission reliability is improved, but manufacturing precision requirements increase
Solution Approach 1:
The capacitive elements are designed with uniform structures that can serve multiple functions: information transmission, galvanic isolation, and potential tuning of capacitance values. This universality allows for standardized manufacturing processes that can accommodate multiple capacitive elements without proportionally increasing precision requirements.
Solution Approach 2:
The capacitance values of the capacitive elements can be tuned or adjusted to optimize performance. By allowing parameter changes in capacitance values, the system can achieve reliable information transmission through multiple elements without requiring extremely precise manufacturing tolerances, as the capacitance can be adjusted post-manufacturing or during operation.
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 enables reliable communication between semiconductor dies with different ground potentials while maintaining galvanic isolation, reducing interference and allowing for efficient energy exchange through capacitive means, thus enhancing the protection and functionality of sensitive devices in harsh environments.
Implementation Method 1
The capacitive interface has a plurality of capacitive elements alternating with a plurality of shielding elements... The capacitive elements are tunable over a range of capacitive values... provides a communication path between the semiconductor dies
Implementation Method 2
The shielding elements in the capacitive interface provides ground shielding between adjacent ones of the capacitive elements... prevent current flow between the functional sections of electrical systems
Implementation Method 3
A first heat sink is coupled to a bottom surface of the ceramic header and provides a mounting surface for a first semiconductor die... The first and second heat sink provide independent ground planes
Data Source
AI summary
An example semiconductor package comprises a ceramic header having a first open space separated from a second open space by a ceramic barrier. A first heat sink is attached to a bottom of the ceramic header below the first open area. A first integrated circuit (IC) die is mounted on the first heat sink. A second heat sink is attached to a bottom of the ceramic header below the second open area. A second IC die is mounted on the second heat sink. A capacitive interface is disposed in the ceramic barrier between the first IC die and the second IC die. The capacitive has a plurality of capacitive elements alternating with a plurality of shielding elements. The capacitive elements are tunable over a range of capacitive values.