Display Circuit Board Impedance Compensation for Signal Integrity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in achieving high-speed signal transmission performance due to the deterioration of characteristic impedance caused by connectors on the circuit board, leading to signal integrity issues.
Innovation Solution
The display device incorporates a circuit board design with a base film having distinct areas, where the connector overlaps one area and is spaced apart in another, featuring unit signal lines with varying characteristic impedances to compensate for impedance changes, and includes components spaced apart to maintain signal integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a connector is disposed on the circuit board to provide electrical connection, then electrical connectivity is improved, but characteristic impedance deteriorates causing signal integrity issues
Solution Approach 1:
The base film is divided into a first area overlapping the connector and a second area spaced apart from the connector. The unit signal line has a first characteristic impedance in the first area and a second characteristic impedance in the second area, where the second impedance is smaller than the first. This local variation in impedance compensates for the impedance change caused by the connector, maintaining overall signal integrity.
2Reliability
If signal lines are extended across the circuit board to connect components, then electrical connectivity is improved, but parasitic capacitance increases degrading signal quality
Solution Approach 1:
The characteristic impedance of the unit signal line is varied along its length, with the first area having a larger impedance and the second area having a smaller impedance. This parameter change compensates for the parasitic capacitance introduced by the connector, thereby maintaining signal integrity despite the extended signal path.
Data Source
AI summary
A display panel including pixels and a circuit board electrically connected to the display panel, wherein the circuit board includes: a base film having a first area overlapping at least a portion of a connector and a second area spaced apart from the connector; and a unit signal line disposed on the base film, electrically connected to the connector, and having a first characteristic impedance in the first area and a second characteristic impedance in the second area, the second characteristic impedance being smaller than the first characteristic impedance.