Galvanic Isolation in Vehicle Diagnostic Interfaces

The patent introduces an isolation barrier as an intermediary component between the vehicle's OBD II port and the diagnostic device. This barrier includes galvanic isolation elements that mediate the signal transmission, blocking direct electrical connections while allowing data communication. The intermediary structure prevents ground loops and voltage spikes from directly affecting either system, resolving the contradiction between protection and complexity.

The patent replaces direct electrical (mechanical) connections with optical or high-impedance coupling methods for signal transmission through the isolation barrier. This substitution allows data to be transmitted without direct galvanic contact, maintaining high transmission speeds while achieving galvanic isolation. The optical coupling mechanism, for example, converts electrical signals to optical signals and back, eliminating the speed penalty associated with traditional isolation methods.

The patent merges multiple isolation functions into a single integrated isolation barrier module. This module combines galvanic isolation, optical coupling, and signal conditioning functions in one compact unit, reducing the overall complexity compared to implementing separate isolation components for each function. The merged structure provides comprehensive protection against voltage variations and ground loops while minimizing the number of discrete components required.