Electroluminescent Display Sensing Circuit MUX-Scaler Architecture

Solution Overview

Problem

Conventional compensation techniques for electroluminescent display devices increase the size and manufacturing cost of sensing circuits due to the need for scalers connected to all sensing channels, making it difficult to maintain uniform driving characteristics across pixels and resulting in luminance deviations.

Innovation Solution

The implementation of a MUX-scaler-MUX connection structure in the sensing circuit, where the number of scalers is less than the number of sampling circuits, with sampling multiplexers dividing outputs into groups and a global multiplexer selectively connecting scaler outputs to an analog-to-digital conversion circuit, reduces the overall number of scalers required.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If scalers are connected to all sensing channels in conventional compensation techniques, then accurate scaling and compensation for driving characteristic differences can be achieved, but the sensing circuit size and manufacturing cost increase

Engineering Contradiction:

Improvecompensation accuracyVSAvoidsensing circuit size

Core Design Contradiction:

Measurement precisionVSArea of stationary object

Solution Approach 1:

The sensing circuit is segmented into multiple groups, with each group containing multiple sampling circuits that share common scalers. This segmentation allows the system to process sensing data from multiple channels through shared resources, reducing the total number of scalers needed while maintaining compensation accuracy for each pixel group.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Scalers are designed with multi-functionality to serve multiple sampling circuit groups. Each scaler can process sensing data from different groups at different time periods, allowing one scaler to perform the function of multiple scalers would otherwise be required, thereby reducing circuit size and manufacturing cost.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Measurement precision

If scalers are connected to all sensing channels in conventional compensation techniques, then accurate scaling and compensation for driving characteristic differences can be achieved, but manufacturing cost increases

Engineering Contradiction:

Improvecompensation accuracyVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The sensing circuit is segmented into multiple groups, with each group containing multiple sampling circuits that share common scalers. This segmentation allows the system to process sensing data from multiple channels through shared resources, reducing the total number of scalers needed while maintaining compensation accuracy for each pixel group.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Scalers are designed with multi-functionality to serve multiple sampling circuit groups. Each scaler can process sensing data from different groups at different time periods, allowing one scaler to perform the function of multiple scalers would otherwise be required, thereby reducing circuit size and manufacturing cost.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Area of stationary object

If the number of scalers is reduced to be less than the number of sampling circuits, then sensing circuit size and manufacturing cost decrease, but circuit complexity increases due to MUX-scaler-MUX connection structure

Engineering Contradiction:

Improvesensing circuit sizeVSAvoidcircuit complexity

Core Design Contradiction:

Area of stationary objectVSDevice complexity

Solution Approach 1:

The circuit employs periodic action through alternating selection of sampling circuit groups by the first and second sampling multiplexers. The scalers periodically process data from different groups in sequence, and the global multiplexer periodically switches between scaler outputs, enabling time-division multiplexing that reduces component count while maintaining functionality.

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

Sampling multiplexers act as intermediaries between the sampling circuits and scalers, and the global multiplexer serves as an intermediary between the scalers and the analog-to-digital conversion circuit. These intermediary components manage the complex routing and switching required to enable fewer scalers to serve more sampling circuits.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS11670223B2Electroluminescent display device for sampling and sensing pixels

Publication Date: 2023.06.06 LG DISPLAY CO LTD

AI summary

An electroluminescent display device includes a display panel including a plurality of pixels connected to a plurality of sensing lines, a plurality of sampling circuits configured to simultaneously sample driving characteristics of the pixels to generate sampling outputs, a plurality of sampling multiplexers configured to divide the sampling outputs into n groups and to alternately select group sampling outputs, a plurality of scalers individually connected to the sampling multiplexers, and a global multiplexer configured to selectively connect outputs of the scalers to an analog-to-digital conversion circuit, wherein the number of scalers is less than the number of sampling circuits.