Comparator Startup Voltage Sequencing to Suppress Switch Glitches

Solution Overview

Problem

Glitch signals generated in comparator circuits can cause malfunctions in switch control systems, especially before digital circuits can detect and limit them, as analog circuits are affected during the initial stages of operation.

Innovation Solution

A comparator circuit with a mode controller that applies a lower operating and reference voltage for a predetermined delay time after power supply initiation, using a delay signal generator, voltage controller, and mode selector to stabilize the voltages and prevent glitch signal generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a comparator circuit operates immediately after power supply initiation, then the system responds quickly, but glitch signals are generated causing switch malfunctions

Engineering Contradiction:

Improveresponse speedVSAvoidswitch operation reliability

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The mode controller applies a first operating voltage and first reference voltage to the comparator before normal operation begins. This preliminary action stabilizes the comparator's initial state and prevents glitch signal generation when the switch is first activated, thereby maintaining both quick response and reliable operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the operating parameters (voltage levels) of the comparator based on the operational phase. During initial power supply, different voltage parameters are applied compared to normal operation. This parameter adjustment prevents glitch generation while maintaining fast response capability.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If a digital circuit is used to detect and limit glitch signals, then glitch detection capability is improved, but the analog circuit is already affected before the digital circuit can respond

Engineering Contradiction:

Improveglitch detection precisionVSAvoidresponse time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

Instead of detecting glitches after they occur, the mode controller performs preliminary action by applying appropriate voltages to the comparator before normal operation. This prevents glitch generation at the source, eliminating the time delay associated with digital detection and correction.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The mode controller acts as an intermediary between the power supply and the comparator circuit. It manages the voltage application sequence to prevent glitch conditions, serving as a mediator that protects the analog circuit from harmful effects before they can occur.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Use of energy by moving object

If the comparator circuit uses standard operating voltages from power supply initiation, then power utilization is efficient, but glitch signals are generated due to unstable initial states

Engineering Contradiction:

Improvepower utilization efficiencyVSAvoidglitch signal generation

Core Design Contradiction:

Use of energy by moving objectVSObject-generated harmful factors

Solution Approach 1:

The mode controller applies a first operating voltage and first reference voltage to the comparator before normal operation begins. This preliminary action stabilizes the comparator's initial state and prevents glitch signal generation when the switch is first activated, thereby maintaining both quick response and reliable operation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system changes the operating parameters (voltage levels) of the comparator based on the operational phase. During initial power supply, different voltage parameters are applied compared to normal operation. This parameter adjustment prevents glitch generation while maintaining fast response capability.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS11476840B2Comparator circuit and switch control device including the same

Publication Date: 2022.10.18 SAMSUNG SDI CO LTD

AI summary

A comparator circuit includes: a comparator comprising: a first input terminal receiving an input voltage; a second input terminal receiving a reference voltage; an output terminal outputting an output signal according to a result of a comparison between the input voltage and the reference voltage; and a power supply terminal receiving an operating voltage; and a mode controller applying a first operating voltage and a first reference voltage to the second input terminal and the power supply terminal of the comparator for a predetermined delay time in response to a supply of power being initiated from a power supply, and applying a second operating voltage and a second reference voltage to the second input terminal and the power supply terminal of the comparator in response to the delay time elapsing, wherein the first operating voltage is higher than a ground voltage and is lower than the second operating voltage.