Display Driver IC Slew-Rate Compensation for Data Line Delay

Solution Overview

Problem

Differences in data line lengths within display panels lead to variations in resistance, causing inconsistent charging and discharging speeds, resulting in poor display uniformity and quality due to differing delay times across the panel.

Innovation Solution

A driving integrated circuit (IC) with a compensation control circuit that adjusts the slew rates of output buffer circuits to compensate for resistance differences between data lines, ensuring consistent charging and discharging speeds across the panel.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of stationary object

If data lines are extended to cover larger display panels, then the display area increases, but the resistance differences among data lines become larger causing poor display uniformity

Engineering Contradiction:

Improvedisplay areaVSAvoiddisplay uniformity

Core Design Contradiction:

Area of stationary objectVSManufacturing precision

Solution Approach 1:

The patent applies local quality by adjusting the slew rates of different output buffer circuits based on their specific positions and corresponding data line characteristics. Each output buffer circuit is configured with a tailored slew rate to compensate for the resistance of its associated data line, ensuring that pixels across the entire display panel are charged uniformly despite varying data line lengths and resistances.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the slew rate parameter of output buffer circuits to compensate for resistance variations in data lines. By dynamically adjusting the slew rate based on data line resistance characteristics, the system maintains consistent charging speeds across all pixels, thereby preserving display uniformity as the display area increases.

Inventive Principle:

Principle #35Parameter changes

2Area of stationary object

If data line lengths are made different to cover various pixel positions, then the display coverage improves, but the delay times for transmitting pixel voltages become inconsistent

Engineering Contradiction:

Improvedisplay coverageVSAvoiddelay time consistency

Core Design Contradiction:

Area of stationary objectVSLoss of time

Solution Approach 1:

The patent implements local quality by assigning different slew rates to output buffer circuits based on their specific locations and corresponding data line characteristics. This localized adjustment ensures that each pixel receives its voltage within a consistent time window, compensating for the varying path lengths and resistances of different data lines.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies preliminary anti-action by pre-configuring different slew rates for output buffer circuits based on anticipated data line resistance variations. This proactive compensation approach counteracts the expected delay time inconsistencies before they occur, ensuring uniform pixel voltage transmission across the display panel.

Inventive Principle:

Principle #9Preliminary anti-action

3Measurement precision

If the resolution of the display panel is increased, then the image quality improves, but the charging duration decreases and resistance differences become more intolerable

Engineering Contradiction:

Improvedisplay resolutionVSAvoidcharging consistency

Core Design Contradiction:

Measurement precisionVSManufacturing precision

Solution Approach 1:

The patent changes the slew rate parameter of output buffer circuits to compensate for resistance variations in data lines. By dynamically adjusting the slew rate based on data line resistance characteristics, the system maintains consistent charging speeds across all pixels, thereby preserving display uniformity as the display area increases.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by adjusting the slew rates of different output buffer circuits based on their specific positions and corresponding data line characteristics. Each output buffer circuit is configured with a tailored slew rate to compensate for the resistance of its associated data line, ensuring that pixels across the entire display panel are charged uniformly despite varying data line lengths and resistances.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS10902816B2Integrated circuit for driving display panel and fan-out compensation method thereof

Publication Date: 2021.01.26 NOVATEK MICROELECTRONICS CORP

AI summary

A driving integrated circuit (IC) and a fan-out compensation method thereof are provided. The driving IC includes a plurality of driving channel circuits, a plurality of output buffer circuits and a compensation control circuit. The input terminals of the output buffer circuits are coupled to the output terminals of the driving channel circuits in a one-to-one manner. The output terminals of the output buffer circuits are coupled a plurality of data lines of a display panel in a one-to-one manner. The compensation control circuit is coupled to the output buffer circuits for adjusting the slew rate of the output terminals of the output buffer circuits to compensate difference in delay times between the data lines of the display panel.