Galvanic Isolation Circuit Layout for Increased Creepage Distance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical circuits face design constraints due to stringent requirements for creepage distance in galvanic isolation, which are influenced by both voltage and frequency levels, limiting design freedom, especially in high-frequency applications.
Innovation Solution
Incorporating a conductive trace connected to a Low Frequency voltage node between the primary and secondary terminals of an electrical component, such as a transformer, to increase the creepage distance by altering the route of potential flow, thereby reducing the stringent creepage requirements for high-frequency signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If galvanic isolation is implemented with standard creepage distance requirements, then safety is ensured, but design freedom is limited
Solution Approach 1:
The patent segments the creepage distance requirement by introducing a conductive trace that divides the path between primary and secondary terminals. This creates separate zones with different frequency characteristics, allowing different creepage requirements to apply to different segments of the overall path.
Solution Approach 2:
The patent applies different creepage distance requirements to different local regions of the circuit board. The area near the primary terminal (high frequency) has different requirements than the area near the secondary terminal (low frequency), allowing optimized design for each local condition.
2Reliability
If creepage distance is increased to meet high-frequency requirements, then safety compliance is achieved, but design flexibility is reduced
Solution Approach 1:
The patent introduces a dynamic element (the conductive trace) that changes the effective creepage path based on frequency. High-frequency signals must follow a longer path avoiding the trace, while low-frequency signals can take a more direct route, providing frequency-dependent safety margins.
Solution Approach 2:
The conductive trace acts as an intermediary element that mediates between the primary and secondary terminals. It creates an intermediate zone that forces high-frequency signals to travel a longer path, effectively increasing the creepage distance where it is most needed without uniformly increasing distances across the entire circuit.
Data Source
AI summary
An electrical circuit having a galvanic isolation between a High Voltage, HV, circuit part and a Low Voltage, LV, circuit part, wherein said electrical circuit comprises a substrate providing said HV and said LV circuit part, an electrical component for providing said galvanic isolation, said component provided on said substrate and having a primary side connected, with a first primary terminal, to said HV circuit part and a secondary side connected, with a first secondary terminal, to said LV circuit part such that a creepage distance is provided over said substrate between said first primary terminal and said first secondary terminal, a conductive trace provided on said substrate, connected with a first end to a Low Frequency, LF, voltage node in said HV circuit part, wherein a frequency of a voltage potential at said LF voltage node is lower than a frequency of a voltage potential at said first primary terminal, and said conductive trace provided in between said first primary terminal and said first secondary terminal thereby increasing said creepage distance between said first primary terminal and said first secondary terminal.