Breakable Electrical Trace for Secure Data Port Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for securing programmable components in electronic circuits, such as breaking the bus coupon, are insufficient as they do not adequately prevent unauthorized access or reprogramming, as exposed bus parts can be reconstructed to reestablish data links.
Innovation Solution
Incorporating a breakable electrical trace with a fusible segment within the substrate, which breaks upon injection of an electric current exceeding a predetermined threshold, physically isolating data ports and requiring damage to the substrate for access, thereby enhancing security by making it difficult to reconnect the data link.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a simple break in the bus coupon is used to make the bus inoperative, then the implementation is simple, but the security level is insufficient as exposed parts can be reconstructed
Solution Approach 1:
The electrical connection is divided into multiple segments: exposed conductive parts and buried fusible segments within the substrate. The fusible segments are embedded in the substrate thickness, creating a segmented structure where critical parts are hidden and protected, while only non-critical parts are exposed. This segmentation prevents reconstruction of the complete data link even if exposed parts are accessed.
Solution Approach 2:
The fusible segments are positioned in the thickness dimension of the substrate, moving the critical breaking point from the surface plane to the vertical dimension. This three-dimensional arrangement hides the fusible segments within the substrate bulk, making them inaccessible from the surface while maintaining electrical connectivity during normal operation. The current injection terminals access these buried segments through vias or conductive paths.
2Reliability
If the bus is made inoperative by breaking the coupon to protect against intrusions, then security is improved, but the exposed parts remain accessible and can be reconstructed
Solution Approach 1:
The substrate acts as an intermediary medium that embeds and protects the fusible segments. Rather than exposing the critical breaking points on the surface, the substrate material surrounds and shields these segments, making them inaccessible to external tools. The current injection terminals serve as controlled intermediaries that can deliver current to the buried segments through defined paths without exposing the segments themselves.
3Reliability
If breakable electrical traces with fusible segments are embedded in the substrate thickness, then security is significantly improved by physical isolation, but the device complexity increases
Solution Approach 1:
The fusible segments are merged with the substrate structure itself, utilizing the substrate material and manufacturing processes to create the security feature. Rather than adding separate protective components or layers, the fusible segments are integrated into the substrate thickness during fabrication, combining the substrate's structural function with the security function in a single unified structure.
Solution Approach 2:
The substrate structure provides its own protective function by embedding the fusible segments within its thickness. The substrate material itself serves as the protective medium, eliminating the need for additional protective layers or encapsulation structures. The manufacturing process leverages the substrate's inherent properties to create both the electrical connection and the security feature simultaneously.
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 effectively prevents unauthorized access to data ports by ensuring that any attempt to access the data ports would require damaging the substrate, thereby irreversibly damaging the electronic circuit, thus significantly compromising intrusion attempts.
Implementation Method 1
a breakable electrical trace located in the thickness of the substrate and extending between the data port and the injection terminal, each breakable electrical trace comprising a fusible segment and being configured to break, by melting of the fusible segment, upon the injection, at the injection terminal, of an electric current having an intensity greater than a predetermined trace breaking threshold
Data Source
AI summary
The invention relates to an electronic circuit comprising a substrate and at least one electronic component (3, 6),each electronic component (3, 6) including at least one data port (12) for receiving data,the electronic circuit (2) further comprising, for each data port (12):a current injection terminal (8);a breakable electrical trace (10) located in the thickness of the substrate and extending between the data port (12) and the injection terminal (8),each breakable electrical trace (10) comprising a fusible segment (20) and being configured to break, by melting of the fusible segment (20), upon the injection, at the injection terminal (8), of an electric current (I) having an intensity greater than a predetermined trace breaking threshold.