Power Source Switching Control for Electronic Devices

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electronic devices with multiple power sources face challenges in smoothly switching power sources without causing instantaneous interruption when power supply lines are shut off between the device body and external devices, as previous techniques require large capacitors or batteries and lack clear criteria for switching between multiple power sources.

Innovation Solution

An electronic device with an order-of-priority setting unit, power source-switching preparation unit, and power source-switching control unit that manages the switching of battery and adapter power sources between the device body and external device, shifting the system to an electric power-saving state and ensuring continuous power supply by prioritizing power sources based on availability and capacity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If power source supply lines are shut off between device body and external device, then instantaneous interruption is prevented during normal operation, but power source switching becomes difficult without causing instantaneous interruption

Engineering Contradiction:

Improveprevention of instantaneous interruptionVSAvoidpower source switching capability

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The system performs preliminary actions by accumulating electric charges in capacitors and shifting to a power-saving state before actual power source switching occurs. This preparation ensures that when switching is needed, the accumulated energy can bridge the gap and prevent instantaneous interruption, thus resolving the contradiction between maintaining shut-off reliability and enabling smooth switching operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

Capacitors are introduced as intermediary energy storage elements between the power sources and the load. These capacitors accumulate charges during normal operation and release them during switching transitions, acting as a mediator that prevents instantaneous interruption while allowing power source supply lines to remain shut off during normal operation.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If a capacitor with large capacitance or battery with large capacity is used to prevent instantaneous interruption, then power source switching can be achieved, but device size and cost increase

Engineering Contradiction:

Improveprevention of instantaneous interruptionVSAvoidcapacitance or battery capacity

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes operational parameters by shifting to a power-saving state before switching, reducing the power consumption during the transition period. This parameter change allows smaller capacitors to provide sufficient energy for the switching process, avoiding the need for large capacitance or battery capacity while still preventing instantaneous interruption.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If multiple power sources are mounted on device body and external device, then power supply flexibility is improved, but determining switching criteria becomes complex

Engineering Contradiction:

Improvepower supply flexibilityVSAvoidswitching control complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The system employs feedback mechanisms by monitoring the connection state of the external device and the availability of power sources. Based on this feedback information, the control unit automatically determines the appropriate switching criteria and executes power source transitions, simplifying the complexity of managing multiple power sources while maintaining flexible power supply capability.

Inventive Principle:

Principle #23Feedback

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

Enables smooth power source switching while preventing instantaneous interruption, even with insufficient capacitance or battery capacity, by prioritizing power sources and using accumulated charges for switching preparation and control.

Implementation Method 1

a capacitor having large capacitance or a secondary battery having a large capacity is required to prevent instantaneous interruption

Methodology Applied

Scientific EffectCapacitance: Capacitance

Implementation Method 2

a loss (voltage drop) is generated by a backflow prevention element, such as a diode

Methodology Applied

Scientific EffectDiode rectification: Diode

Data Source

PatentUS10644533B2Electronic device, imaging apparatus, and method of switching power source

Publication Date: 2020.05.05 FUJIFILM CORP

AI summary

An electronic device, an imaging apparatus, and a method of switching a power source that can smoothly switch a power source while preventing instantaneous interruption in a case where power source supply lines are shut off from each other between a device body and an external device on which a plurality of power sources can be mounted. A power source-switching preparation unit performs first processing for shifting an electronic device to an electric power-saving state and second processing for shifting the electronic device to a state where electric power can be supplied from a plurality of power sources, as switching preparation, and a power source-switching control unit switches a main power source according to a set order of priority in a state where the switching preparation is performed.