Battery Power Calculation Circuit Using Voltage Data Lookup

Solution Overview

Problem

Existing methods for calculating remaining battery power in portable devices face accuracy issues due to varying battery output voltage with load current and internal resistance, and methods using charging/discharging current detection require additional components that increase costs and reduce efficiency.

Innovation Solution

A remaining battery power calculation circuit that includes a detection unit for output voltage, a data storage unit with current value data, and a calculation unit to determine charging/discharging current, allowing for accurate power calculation without direct current detection, using pre-stored data to correlate voltage and power ratios.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a resistor is connected in series to detect charging/discharging current, then measurement precision of current is improved, but use of energy by stationary object deteriorates due to efficiency loss

Engineering Contradiction:

Improvecurrent detection accuracyVSAvoidpower source efficiency

Core Design Contradiction:

Measurement precisionVSLoss of energy

Solution Approach 1:

The patent creates a virtual copy of the current detection function through calculation rather than physical measurement. By storing pre-measured voltage-current relationship data and using output voltage to calculate current via lookup tables and interpolation, the system replicates current detection capability without physical current-sensing resistors, thereby eliminating energy loss while maintaining measurement precision.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent replaces the physical electrical measurement system (series resistor-based current detection) with a computational system. Instead of using ohmic resistance to measure current, the invention uses stored data tables and mathematical calculations based on voltage measurements to determine current, substituting mechanical/electrical measurement with information processing.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If a resistor is connected in series to detect charging/discharging current, then measurement precision of current is improved, but device complexity increases due to additional components

Engineering Contradiction:

Improvecurrent detection accuracyVSAvoidbattery pack component count

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent creates a virtual copy of the current detection function through calculation rather than physical measurement. By storing pre-measured voltage-current relationship data and using output voltage to calculate current via lookup tables and interpolation, the system replicates current detection capability without physical current-sensing resistors, thereby eliminating energy loss while maintaining measurement precision.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent replaces the physical electrical measurement system (series resistor-based current detection) with a computational system. Instead of using ohmic resistance to measure current, the invention uses stored data tables and mathematical calculations based on voltage measurements to determine current, substituting mechanical/electrical measurement with information processing.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If output voltage is used to calculate remaining battery power, then device complexity is reduced, but measurement precision of battery power deteriorates due to voltage variation with load current

Engineering Contradiction:

Improvedetection circuit simplicityVSAvoidbattery power calculation accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent transforms the single-parameter voltage-based calculation into a multi-parameter calculation system. By incorporating current information (derived from voltage through stored relationships) and using composite calculation methods that consider both voltage and calculated current, the system improves battery power measurement precision while maintaining relative simplicity through data-driven approaches.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a virtual copy of the current detection function through calculation rather than physical measurement. By storing pre-measured voltage-current relationship data and using output voltage to calculate current via lookup tables and interpolation, the system replicates current detection capability without physical current-sensing resistors, thereby eliminating energy loss while maintaining measurement precision.

Inventive Principle:

Principle #26Copying

Data Source

PatentUS9261567B2Method for determining a power level of a battery and circuit therefor

Publication Date: 2016.02.16 SEMICON COMPONENTS IND LLC

AI summary

A remaining battery power calculation circuit includes: a detection unit configured to detect an output voltage of a battery; a data storage unit configured to store data in an associated manner with each of a plurality of current values for charge or discharge of the battery, the data indicating a relationship between the output voltage and a ratio of remaining power of the battery to a capacity of the battery in a case where the battery is charged or discharged with each of the plurality of current values; and a first calculation unit configured to calculate a charging/discharging current of the battery based on the data and the output voltage.