Offset Slot Conductor Structure for Smart Card Leadframe Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conductor track structures used in smart card applications face mechanical instability due to slots separating adjacent conductor tracks being misaligned between different levels, leading to potential short circuits and functional impairments during bonding processes.

Innovation Solution

The slots separating adjacent conductor tracks on the first and second conductor track levels are offset relative to each other, eliminating the need for conductive material in edge regions and enhancing mechanical stability by ensuring the insulator provides cohesion between the levels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If slots separating adjacent conductor tracks are aligned between first and second conductor track levels, then electrical isolation between conductor tracks is achieved, but mechanical stability and torsional rigidity of the structure deteriorate

Engineering Contradiction:
Improveelectrical isolationVSAvoidmechanical stability
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent applies dimensional offset by shifting the slots of the first conductor track level relative to the slots of the second conductor track level in the vertical dimension. This staggered arrangement ensures that slots do not align between levels, allowing the insulator material to bridge between levels and provide both electrical isolation and mechanical continuity, thereby resolving the contradiction between electrical isolation and mechanical stability.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If slots are positioned to separate conductor tracks effectively, then electrical isolation is improved, but the cohesion between conductor track levels deteriorates due to reduced insulator support

Engineering Contradiction:
Improveelectrical isolationVSAvoidcohesion between levels
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

By offsetting slots in the vertical dimension between levels, the insulator material continues to provide cohesive support between conductor track levels without being interrupted by aligned slot openings. This maintains structural integrity while preserving electrical isolation functionality.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Ease of manufacture

If aligned slots are used for conductor track separation, then manufacturing process is simplified, but the risk of unwanted electrical contacts during separation increases

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidunwanted electrical contacts
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The staggered slot arrangement in the vertical dimension prevents direct alignment between conductor tracks of different levels, thereby eliminating the risk of unwanted electrical contacts during separation processes while maintaining manufacturing simplicity through consistent slot formation techniques.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP3456160B1Circuit pattern structure, in particular for a leadframe for a smart card application, with at least two superposed planes of conductive patterns
Publication Date: 2019.07.03 LINXENS HOLDING SAS
  • EP3456160B1 patent drawingFigure 1
  • EP3456160B1 patent drawingFigure 2
  • EP3456160B1 patent drawingFigure 3

AI summary

The invention relates to a conductor path structure, in particular for a lead-frame for a smart card application, which comprises at least one first conductor path plane (10) with several first conductor paths (11; 11a-11f) and at least one second conductor path plane (20) with several second conductor paths (21; 21a-21f). Superimposed conductor path planes (10, 20) are separated by an insulator (30), at least one first conductor path (11, 11a, 11b, 11c, 11d, 11f) of the first conductor path plane (10) comprises at least one through-extending connection opening (12; 12a-12e), through which a connection wire can be guided and can be placed in electrically conductive contact with the conductor path (21; 21a-21f) of the second conductor path planes (20). At least two adjacent conductor paths (11; 11a, 11b; 11b, 11c; 11d, 11e; 11e, 11f) of the first conductor path plane (10) are separated from each other by slots (13; 13a-13i) and at least two adjacent conductor paths (21a, 21b; 21b, 21c, 21d, 21e; 21e, 21f) are separated from each other by further slots (23a-23e). According to the invention, the slots (13; 13a-13i) separating one or more adjacent conductor paths (11; 11, 11a, 11b, 11c, 11d, 11f) of the first conductor path plane (10) and other slots (11 or 23) separating the adjacent conductor paths (21; 21a-21f) of the second conductor path plane (20) are arranged offset to each other.