Multiplexer Reduces Touch Sensor Wiring
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Solution Overview
Problem
Input devices with proximity sensors, such as touchpads and touch screens, have numerous connections to ICs, which are costly and occupy valuable space, limiting their efficiency and usability.
Innovation Solution
The implementation of a multiplexer on a glass layer within the input device that selectively couples transmitter and receiver electrodes to a sensing channel based on a control signal, reducing the number of connections needed between the sensing module and the integrated controller (IC).
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple connections are used between sensing module and IC, then sensing capability is improved, but device complexity and space consumption increase
Solution Approach 1:
The multiplexer circuit performs multiple functions: it routes signals from multiple sensing elements to a single IC interface, enabling one component to handle what would traditionally require multiple separate connections. This reduces the overall connection count while preserving full sensing capability across all electrodes.
Solution Approach 2:
The multiplexer acts as an intermediary component between the sensing module and the IC. It mediates the signal transmission by selectively connecting different sensing elements to the IC's single interface, thereby reducing direct connection requirements while maintaining signal integrity.
2Adaptability or versatility
If multiple connections are used between sensing module and IC, then sensing coverage is improved, but manufacturing cost increases
Solution Approach 1:
The multiplexer enables a single IC interface to serve multiple sensing elements, reducing the total number of connections required. This decreases manufacturing complexity and cost while maintaining comprehensive sensing coverage across all electrodes through time-division or signal-division multiplexing.
3Measurement precision
If multiple connections are used between sensing module and IC, then signal transmission accuracy is improved, but space consumption increases
Solution Approach 1:
The multiplexer serves as a space-efficient intermediary that consolidates multiple signal transmission paths into a single interface. It maintains signal transmission accuracy by selectively routing signals from different sensing elements without requiring physical proximity or additional routing space for each connection.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration reduces the number of connections required, thereby decreasing costs and space usage while enhancing the usability and efficiency of the input device by simplifying the communication between the sensing module and the IC.
Implementation Method 1
a plurality of transmitter electrodes disposed on the first glass layer and configured for capacitance sensing; a plurality of receiver electrodes disposed on the second glass layer and configured for capacitance sensing
Data Source
AI summary
An input device, including: a first glass layer; a plurality of transmitter electrodes disposed on the first glass layer and configured for capacitance sensing; a second glass layer; a plurality of receiver electrodes disposed on the second glass layer and configured for capacitance sensing; and a multiplexer disposed on the first glass layer and coupled to a plurality of sources and a sensing channel, where the multiplexer selectively couples one of the plurality of sources to the sensing channel based on at least a control signal, and where the plurality of sources includes the plurality of transmitter electrodes and the plurality of receiver electrodes.