Keyboard Pin Level Switching to Prevent Oxide-Induced Scan Errors

Solution Overview

Problem

Electronic devices with keyboards experience erroneous key scanning results due to abnormal oxides forming on circuitry, leading to reduced service life and user experience.

Innovation Solution

A level setting method is employed to configure output pins of the keyboard to different voltage levels based on its use status, reducing potential differences between input and output pins to retard oxide formation and improve scanning accuracy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the keyboard is used for a period of time, then the keyboard can perform key scanning operations, but abnormal oxides are generated on the circuit which causes erroneous key scanning results and reduces service life

Engineering Contradiction:

Improvekey scanning operation capabilityVSAvoidkey scanning result accuracy

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The patent applies preliminary action by configuring output pins to a first level (same as input pins) when the keyboard is in off state, before any key scanning operation occurs. This preemptive configuration prevents potential difference from existing during non-use periods, thereby retarding oxide formation on the circuit before it can cause reliability issues during subsequent use.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamics by dynamically adjusting the configuration of output pins based on the keyboard's use status. When the keyboard is in on state, output pins are configured to second or third levels to enable proper key scanning operations. When in off state, output pins are configured to first level to minimize potential difference. This dynamic adaptation allows the system to optimize between productivity and reliability based on operational needs.

Inventive Principle:

Principle #15Dynamics

2Productivity

If the keyboard is used for a period of time, then the keyboard can perform key scanning operations, but the service life of the keyboard is reduced due to oxide generation

Engineering Contradiction:

Improvekey scanning operation capabilityVSAvoidkeyboard service life

Core Design Contradiction:

ProductivityVSDuration of action of stationary object

Solution Approach 1:

The patent applies preliminary action by configuring output pins to a first level (same as input pins) when the keyboard is in off state, before any key scanning operation occurs. This preemptive configuration prevents potential difference from existing during non-use periods, thereby retarding oxide formation on the circuit before it can cause reliability issues during subsequent use.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements periodic action by periodically switching the configuration of output pins between first level (during off state) and second/third levels (during on state). This periodic adjustment creates intervals where no potential difference exists, allowing the circuit to rest and reducing cumulative oxide formation over time, thereby extending keyboard service life while maintaining operational capability.

Inventive Principle:

Principle #19Periodic action

3Productivity

If potential difference between input pin and output pin is maintained for extended duration, then key scanning can be performed, but oxide generation accelerates causing erroneous scanning results

Engineering Contradiction:

Improvekey scanning operation capabilityVSAvoidkey scanning result accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by configuring output pins to a first level (same as input pins) when the keyboard is in off state, before any key scanning operation occurs. This preemptive configuration prevents potential difference from existing during non-use periods, thereby retarding oxide formation on the circuit before it can cause reliability issues during subsequent use.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent implements dynamics by dynamically adjusting the configuration of output pins based on the keyboard's use status. When the keyboard is in on state, output pins are configured to second or third levels to enable proper key scanning operations. When in off state, output pins are configured to first level to minimize potential difference. This dynamic adaptation allows the system to optimize between productivity and reliability based on operational needs.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS20260003440A1Level Setting Method and Electronic Device

Publication Date: 2026.01.01 HONOR DEVICE CO LTD

AI summary

Embodiments of this disclosure are applied to the field of circuit control, and provide a level setting method and an electronic device. When determining that a keyboard is in an off state, an electronic device configures level statuses of all output pins in the keyboard to a first level, to avoid existence of a potential difference between an input pin and an output pin. When the keyboard is in an on state, the electronic device configures levels of all the output pins corresponding to keys on the keyboard to a second level or a third level. When the levels of the output pins are the second level or the third level, the keyboard can generate an interrupt properly when receiving a user's operation of pressing a key, so that the electronic device can determine, based on the interrupt, the key pressed by the user.