Capacitive Feedback Circuit for Dielectric Relaxation Error Cancellation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Semiconductor devices face challenges in accurately operating due to errors caused by dielectric relaxation phenomena, especially in negative feedback circuits where conventional dielectric relaxation countermeasures are not applicable.

Innovation Solution

The semiconductor device incorporates a first capacitive element, a first switch circuit, a first inversion signal generation circuit, a second capacitive element, and a negative feedback circuit. The first inversion signal generation circuit inverts the input voltage and holds it, while the negative feedback circuit generates an output signal based on the voltage of a common node connected to both capacitive elements, thereby applying a feedback signal to cancel out errors due to dielectric relaxation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a negative feedback circuit is applied in semiconductor devices, then the device can perform functions such as AD conversion, but errors caused by dielectric relaxation phenomena occur and operational accuracy deteriorates

Engineering Contradiction:

Improvefunctional capabilityVSAvoidoperational accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent applies feedback by generating an inverted version of the input signal and feeding it through a second capacitive element to a common node. This feedback mechanism creates opposing dielectric relaxation errors that cancel each other out, allowing the negative feedback circuit to function accurately despite the inherent dielectric relaxation phenomena in capacitive elements

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The patent converts the harmful dielectric relaxation phenomenon into a beneficial effect by intentionally introducing a second capacitive element with an inverted input signal. The dielectric relaxation errors from both capacitive elements have opposite polarities and cancel each other out, transforming the harmful effect into a self-correcting mechanism that improves measurement precision

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Reliability

If conventional dielectric relaxation countermeasures are used, then they work for simple circuits, but they are not applicable to negative feedback circuits

Engineering Contradiction:

Improvecountermeasure effectivenessVSAvoidcircuit applicability

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent creates a universal solution that works for both simple circuits and negative feedback circuits by using a symmetric structure with two capacitive elements. The second capacitive element with the inverted signal path ensures that the dielectric relaxation compensation mechanism functions correctly in negative feedback configurations where conventional methods fail

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Duration of action of stationary object

If a first capacitive element is used to hold voltage, then voltage storage is achieved, but dielectric relaxation errors are introduced

Engineering Contradiction:

Improvevoltage holding capabilityVSAvoidvoltage accuracy

Core Design Contradiction:

Duration of action of stationary objectVSMeasurement precision

Solution Approach 1:

The patent applies the counterweight principle by introducing a second capacitive element with an inverted input signal. The dielectric relaxation error from the first capacitive element is counterbalanced by an equal and opposite error from the second capacitive element, allowing voltage to be held over time without accuracy degradation

Inventive Principle:

Principle #8Anti-weight (Counterweight)

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 configuration enables the semiconductor device to operate accurately by suppressing errors caused by dielectric relaxation phenomena, ensuring precise AD conversion and output signal generation.

Implementation Method 1

a first capacitive element, a first switch circuit that applies a first input voltage to one end of the first capacitive element in a sampling mode and holds the first input voltage in the first capacitive element in a hold mode

Methodology Applied

Scientific EffectCapacitance: Capacitance

Implementation Method 2

a first inversion signal generation circuit that generates a voltage that inverts the first input voltage in the sampling mode and holds the generated voltage in the bold mode

Methodology Applied

Scientific EffectVoltage inversion:

Implementation Method 3

a negative feedback circuit that generates an output signal according to the voltage of a first node that is commonly connected to the other end of the first capacitive element and the other end of the second capacitive element in the hold mode and applies a first feedback signal corresponding to the output signal to one end of the first capacitive element

Methodology Applied

Scientific EffectNegative feedback: Feedback

Data Source

PatentUS20250055471A1Semiconductor device

Publication Date: 2025.02.13 RENESAS ELECTRONICS CORP

AI summary

A semiconductor device is provided. The semiconductor device is capable of operating accurately by suppressing errors caused by dielectric relaxation phenomena. The semiconductor device includes a first capacitive element, a first switch circuit, a first inversion signal generating circuit, a second capacitive element, and a negative feedback circuit.