Voltage Measurement Using Capacitor Discharge Timing

Solution Overview

Problem

Conventional chips with integrated supply voltage indicators occupy more resources and are costly, hindering performance and versatility in applications such as electric machine control and consumer electronics.

Innovation Solution

A device comprising a resistor, capacitor, and control unit, including a comparator, reference power supply, timer, and computing unit, measures power supply voltage by calculating the time interval of capacitor discharge, allowing voltage calculation without a dedicated supply voltage indicator, thus reducing resource usage and cost.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a supply voltage indicator is integrated inside the chip, then voltage detection function is achieved, but chip resource occupation increases and cost increases

Engineering Contradiction:

Improvevoltage detection functionVSAvoidchip resource occupation

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The temperature measurement module is made to perform both temperature measurement and voltage detection functions. The same ADC and comparator resources are reused for both functions by sequentially switching between temperature measurement mode and voltage detection mode, eliminating the need for a separate supply voltage indicator module.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The voltage detection function is merged into the existing temperature measurement module. The ADC, comparator, and control logic are combined to serve dual purposes: measuring temperature via thermistor and detecting supply voltage via capacitor discharge timing, thereby reducing overall chip resource occupation.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If a supply voltage indicator is integrated inside the chip, then voltage detection function is achieved, but manufacturing cost increases

Engineering Contradiction:

Improvevoltage detection functionVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The temperature measurement module is made to perform both temperature measurement and voltage detection functions. The same ADC and comparator resources are reused for both functions by sequentially switching between temperature measurement mode and voltage detection mode, eliminating the need for a separate supply voltage indicator module.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent uses a software-controlled timing mechanism to replicate the voltage detection function that would otherwise require dedicated hardware. By using the existing ADC and comparator with a timing algorithm, it creates a functional copy of voltage detection capability without duplicating physical components.

Inventive Principle:

Principle #26Copying

3Measurement precision

If a separate supply voltage indicator is used, then voltage detection accuracy is ensured, but resource occupation and versatility are reduced

Engineering Contradiction:

Improvevoltage detection accuracyVSAvoidchip versatility

Core Design Contradiction:

Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The temperature measurement module is made to perform both temperature measurement and voltage detection functions. The same ADC and comparator resources are reused for both functions by sequentially switching between temperature measurement mode and voltage detection mode, eliminating the need for a separate supply voltage indicator module.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 solution enables accurate voltage measurement within chips, reducing resource occupation and costs while maintaining performance, making it suitable for various applications without the need for a separate supply voltage indicator.

Implementation Method 1

a capacitor, and a control unit. One end of the capacitor is connected with the resistor, while the other end of the capacitor is connected to ground

Methodology Applied

Scientific EffectCapacitor charging and discharging: Capacitance

Implementation Method 2

a resistor, a capacitor, and a control unit. One end of the capacitor is connected with the resistor

Methodology Applied

Scientific EffectResistor: Electrical Resistance

Implementation Method 3

The control unit includes a comparator connected with the capacitor, a reference power supply connected with the comparator

Methodology Applied

Scientific EffectVoltage comparison:

Implementation Method 4

a timer, and a computing unit. The timer is configured to measure a time interval between a start moment when the capacitor begins to discharge after being fully charged and an end moment when a voltage of the capacitor is equal to a voltage of the reference power supply

Methodology Applied

Scientific EffectTime measurement:

Data Source

PatentUS9261540B2Devices for measuring voltage of a power supply, detection devices, and temperature controllers

Publication Date: 2016.02.16 COPELAND COMFORT CONTROL LP

AI summary

Disclosed are exemplary embodiments of devices for measuring voltage of a power supply. Also disclosed are exemplary embodiments of detection devices and temperature controllers comprising such devices for measuring voltage of a power supply. In exemplary embodiments, a device for measuring the voltage of a power supply generally includes a resistor, a capacitor, and a control unit. One end of the capacitor is connected with the resistor, while the other end of the capacitor is connected to ground. The control unit is connected with the power supply. The control unit includes a comparator connected with the capacitor, a reference power supply connected with the comparator, a timer, and a computing unit.