Proximity Sensor Baseline Compensation for Temperature Drift

Solution Overview

Problem

Existing proximity sensing technologies face accuracy issues and increased electromagnetic wave generation due to temperature variations during long calls, particularly when a device is close to a user's face, leading to potential erroneous operations and higher power consumption.

Innovation Solution

A proximity sensor system that includes a reception circuit, a first signal processing circuit, and a temperature detection circuit, which independently detects temperature variations and adjusts baseline values to compensate for temperature changes, eliminating the need for a separate reference channel and reducing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a reference channel is added to compensate for temperature variations, then temperature compensation capability is improved, but device complexity and power consumption increase

Engineering Contradiction:

Improvetemperature compensation capabilityVSAvoidcircuit complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The proximity sensor performs self-compensation by using its own sensing capabilities to detect temperature-induced baseline shifts and automatically adjusting its operation, eliminating the need for external reference channels or additional compensation circuits

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The proximity sensor's sensing circuit serves dual purposes: both detecting proximity of conductive objects and detecting temperature variations that cause baseline shifts, allowing one circuit to perform multiple functions without requiring separate dedicated circuits

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If a reference channel is added to compensate for temperature variations, then temperature compensation capability is improved, but power consumption increases

Engineering Contradiction:

Improvetemperature compensation capabilityVSAvoidpower consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The proximity sensor performs self-compensation by using its own sensing capabilities to detect temperature-induced baseline shifts and automatically adjusting its operation, eliminating the need for external reference channels or additional compensation circuits

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The proximity sensor's sensing circuit serves dual purposes: both detecting proximity of conductive objects and detecting temperature variations that cause baseline shifts, allowing one circuit to perform multiple functions without requiring separate dedicated circuits

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Stability of the object's composition

If temperature compensation is improved using existing methods, then temperature stability is improved, but measurement precision deteriorates due to erroneous operation

Engineering Contradiction:

Improvetemperature stabilityVSAvoidproximity detection accuracy

Core Design Contradiction:

Stability of the object's compositionVSMeasurement precision

Solution Approach 1:

The system continuously monitors the sensing output and uses feedback mechanisms to detect when temperature-induced baseline shifts occur, then automatically adjusts the baseline or triggers recalibration to maintain accurate proximity detection despite temperature variations

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The baseline value is made dynamic rather than fixed, allowing it to automatically adjust in response to detected temperature changes, ensuring that the proximity sensor maintains accuracy across varying temperature conditions

Inventive Principle:

Principle #15Dynamics

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 approach enhances the accuracy of proximity detection, reduces electromagnetic wave generation, and minimizes erroneous operations by adaptively compensating for temperature variations within the proximity sensor, thereby improving the device's operational accuracy and reducing power consumption.

Implementation Method 1

a temperature detection circuit, configured to independently detect a temperature variation of the proximity sensor

Methodology Applied

Scientific EffectTemperature detection:

Implementation Method 2

a reception circuit, configured to receive a first electrical signal generated based on proximity of a conductor

Methodology Applied

Scientific EffectCapacitive sensing: Capacitance

Data Source

PatentUS10782827B2Proximity sensor and method for sensing proximity thereof

Publication Date: 2020.09.22 ABOV SEMICON CO LTD

AI summary

Disclosed are a proximity sensor and a proximity detection method for the proximity sensor. The proximity sensor includes: a reception circuit configured to receive a first electrical signal which is generated based on proximity of the conductor; a first signal processing circuit configured to determine whether or not the conductor is in close proximity to the electronic device by using the first electrical signal, a first baseline value, and a threshold value; a temperature detection circuit configured to detect the temperature of the proximity sensor independently of the first electrical signal; and a second signal processing circuit configured to, when the conductor is in close proximity to the electronic device and also a temperature variation equal to or larger than a reference value is detected by the temperature detection circuit, generate a second baseline value by adding a temporary compensation value to the first baseline value.