POS Keyboard Safety Protection with PVDF Silver Slurry Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing keyboard protection methods are not precise enough to prevent unauthorized access to sensitive data, as attackers can still obtain information by targeting the key gold finger region through methods like holing or piercing, and these methods often have a short lifespan due to frequent or improper operation.
Innovation Solution
A keyboard safety protection device featuring a protection layer composed of a polyvinylidene fluoride (PVDF) film with coated silver slurries, a metal dome, and a silica gel key, which forms a comprehensive safety detection circuit to protect the key gold finger region, including a conductive particle and press protrusion for stable electrical connections, and insulation and waterproof thin film layers for enhanced durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conductive MESH protection circuit is printed directly on the flexible film, then the protection circuit can be formed, but the protection circuit traces are prone to rupturing due to frequent or improper operation, reducing the lifetime of the keyboard protection board
Solution Approach 1:
The patent uses a PVDF film as the base layer instead of a conventional flexible film. The PVDF film provides both flexibility for keyboard operation and enhanced mechanical strength to prevent trace rupturing. The metal dome structure further protects the conductive traces by providing a rigid protective shell that absorbs operational stress.
Solution Approach 2:
The patent employs a composite structure combining PVDF film, metal dome, conductive adhesive, and PCB substrate. This multi-material composite approach integrates the flexibility of PVDF, the structural protection of metal dome, and the electrical conductivity of conductive adhesive, creating a protection board that resists trace rupturing while maintaining operational flexibility.
2Reliability
If gaps or insulation matters are disposed between two lines printed on the conductive MESH protection circuit, then the circuit can be formed, but attackers can find loopholes to attack and steal high sensitive data stored information
Solution Approach 1:
The patent introduces a PVDF film as an intermediary layer between the metal dome and the PCB. This film serves as both a structural component and a protective barrier that covers the gold finger region. The conductive adhesive patterned on the PVDF film creates electrical connections while the PVDF itself provides physical coverage, eliminating gaps that attackers could exploit.
Solution Approach 2:
The patent applies conductive adhesive in specific localized patterns rather than uniform coverage. The conductive traces are strategically placed to create electrical connections where needed while maintaining coverage over critical areas. This localized approach provides security without requiring complete opaque coverage, balancing security with functional requirements.
3Reliability
If a tamper-evident contact is disposed on the keyboard PCB and covered by conductive adhesive through the housing, then the tamper-evident detection circuit can be activated, but the attacker may not contact the tamper-evident contact and attack the key gold finger region through holing or piercing the housing
Solution Approach 1:
The patent merges the tamper detection function with the gold finger protection function into a single integrated structure. The PVDF film covers both the gold finger region and incorporates conductive adhesive patterns that serve as both protective coverage and tamper detection elements. This unified approach ensures that any attempt to access the gold finger region will necessarily interact with the conductive adhesive, triggering the tamper detection circuit.
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 provides comprehensive protection against unauthorized access by ensuring stable electrical connections and preventing data theft, while the PVDF film and silver slurries enhance the physical protection and longevity of the device, reducing the risk of circuit rupture and improving overall durability.
Implementation Method 1
the first and second silver slurries are coated on the surface of the PVDF film, the surfaces of the first and second silver slurries are provided with a first and second thin film layers respectively, the first and second silver slurries are electrically connected with the key gold finger
Implementation Method 2
the key gold finger is provided with a conductive particle configured to facilitate the electrical connection of the second contact and the key gold finger
Data Source
AI summary
A keyboard safety protection device for protecting a point of sale (POS) device keyboard area from being attacked includes: a protection layer, a metal dome, and a keyboard printed circuit board, wherein a key gold finger and a safety processor are arranged on the keyboard PCB, the protection layer is composed of a layer of PVDF film and a first and second silver slurries, the first and the second silver slurries are coated on the surface of the PVDF film, the surfaces of the first and second silver slurries are provided with a first and second thin film layers respectively, the first and second silver slurries are electrically connected with the key gold finger, and the first and second silver slurries are electrically connected with the safety processor to form a safety detection circuit through the keyboard printed circuit board and the safety processor.