Display Sensing Circuit With Common Amplifier for Accurate Pixel Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sensing circuits in display apparatuses face accuracy issues due to deviations in feedback capacitances and voltage differences between input terminals of sensing amplifiers, leading to decreased sensing accuracy of switching elements in pixels, which affects display quality.

Innovation Solution

A sensing circuit utilizing a common sensing amplifier connected to an analog-to-digital converter for multiple sensing lines, reducing the impact of feedback capacitance deviations and voltage differences, thereby increasing sensing accuracy and display quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple sensing amplifiers are used for different sensing lines, then each line can be sensed independently, but the sensing accuracy decreases due to deviations in feedback capacitances and voltage offsets between amplifiers

Engineering Contradiction:
Improveindependent sensing capabilityVSAvoidsensing accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent merges multiple sensing amplifiers into a single shared sensing amplifier that serves multiple sensing lines. This is achieved by providing a single sensing amplifier with its output connected to an analog-to-digital converter, and the input of the sensing amplifier receiving signals from multiple sensing lines through switching circuitry. This consolidation eliminates the feedback capacitance deviation and voltage offset issues that arise from using multiple separate amplifiers, thereby improving sensing accuracy while maintaining the ability to sense multiple lines independently through temporal multiplexing.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sensing amplifier is designed to perform multiple functions by serving as a universal amplifier for all sensing lines. Instead of dedicating one amplifier per sensing line, a single sensing amplifier is configured to sequentially process signals from multiple sensing lines through control switches. This multi-functional approach reduces the number of amplifiers needed and eliminates the precision degradation caused by manufacturing variations between multiple amplifiers.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If a common sensing amplifier is used for multiple sensing lines, then sensing accuracy increases by eliminating feedback capacitance deviations and voltage offsets, but the complexity of signal routing and switching increases

Engineering Contradiction:
Improvesensing accuracyVSAvoidsignal routing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the signal routing into distinct time intervals, with each sensing line being connected to the common sensing amplifier during its designated time slot. This temporal segmentation is controlled by switching circuitry that connects one sensing line at a time to the sensing amplifier. By dividing the operation into discrete time segments, the patent manages the complexity of routing multiple signals through a single amplifier without requiring complex simultaneous signal handling.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent employs dynamic switching to connect different sensing lines to the common sensing amplifier at different times. The switching circuitry is controlled dynamically based on which sensing line needs to be measured, allowing the system to adapt its configuration in real-time. This dynamic approach simplifies the overall architecture compared to having static dedicated amplifiers for each line, while still enabling accurate sensing of all lines through time-multiplexed operation.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3965100B1Sensing circuit
Publication Date: 2024.05.22 SAMSUNG DISPLAY CO LTD
  • EP3965100B1 patent drawingFigure 1
  • EP3965100B1 patent drawingFigure 2
  • EP3965100B1 patent drawingFigure 3~4

AI summary

A sensing circuit includes a first input selecting circuit connected to a first sensing line and a second sensing line, a first path setting circuit that sets a path of a first sensing signal received from the first sensing line or a path of a second sensing signal received from the second sensing line, a second path setting circuit that sets a path of a sensing reference voltage, a first switch matrix connected to the first path setting circuit and the second path setting circuit, a first mode setting circuit connected to a first output terminal of the first switch matrix, a first common sensing amplifier connected to the first mode setting circuit, a second mode setting circuit connected to a second output terminal of the first switch matrix, and a second common sensing amplifier connected to the second mode setting circuit.