LCD Data Drive IC Output Compensation Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LCD data drive ICs face challenges in achieving uniform image display due to varying impedances of data lines, which leads to non-uniform charging times and requires serpentine line sections that occupy excessive space, especially in narrow-frame designs, and results in electromagnetic interference (EMI) when all output channels are activated simultaneously.
Innovation Solution
The implementation of an output compensation circuit with delay control units and switch units in the data drive IC, which generates delay control signals based on impedance values to synchronize the charging time of pixel electrodes, eliminating the need for serpentine line sections and reducing routing space, while ensuring uniform image display.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If serpentine line sections are used to compensate for impedance differences, then uniform image display is achieved, but routing space increases
Solution Approach 1:
The patent changes the timing parameter of signal output by introducing delay control units that provide different delay amounts to different output channels. This compensates for impedance differences without requiring serpentine line sections, thus maintaining uniform image display while reducing routing space.
Solution Approach 2:
The patent applies preliminary action by pre-calculating and pre-setting different delay amounts for each output channel based on their respective impedance characteristics. This allows the system to compensate for impedance differences before the signal is actually output, eliminating the need for physical serpentine adjustments.
2Productivity
If all output channels are activated simultaneously, then productivity is improved, but electromagnetic interference increases
Solution Approach 1:
The patent applies periodic action by sequentially activating output channels in different cycles rather than simultaneously. The delay control units ensure that channels with different impedances are activated at different times within each frame period, reducing peak current and electromagnetic interference while maintaining overall productivity.
3Manufacturing precision
If serpentine line sections are used to make data line impedances equal, then charging time uniformity is improved, but device complexity increases
Solution Approach 1:
The patent replaces the mechanical/physical serpentine line structure with an electronic delay control system. Instead of physically adjusting line lengths and materials to equalize impedances, the system uses delay control units to electronically compensate for impedance differences, simplifying the wiring scheme while maintaining charging time uniformity.
Data Source
AI summary
An output compensation circuit and an output compensation method for an LCD data drive IC as well as an LCD comprising the same are disclosed. The output compensation circuit comprises a data drive IC, a plurality of first switch units and a plurality of delay control units. A plurality of output channels of the data drive IC each are connected with a corresponding row of pixel electrodes on a glass substrate via a data line respectively to output a charging signal. Each of the first switch units control the corresponding output channel according to a delay control signal generated by the corresponding delay control unit. Each of the delay control units is configured to generate the delay control signal-used to control the first switch unit to be turned on after a predetermined delay so that the charging time is the same for all the pixel electrodes.