Compact Duty Cycle Correction Circuit Without VCO Overhead

Solution Overview

Problem

Existing data communication systems face challenges in accurately detecting signal loss and maintaining optimal duty cycle, particularly in high-data applications like social networks, where conventional methods are inadequate and inefficient.

Innovation Solution

The implementation of a duty cycle correction device using a pair of transistors and a duty cycle sensor to generate correction signals, which are applied to the output clock signal, allowing for fine digital correction and minimizing input capacitance and power consumption by omitting the voltage-controlled oscillator.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional duty cycle correction methods are used, then duty cycle accuracy can be improved, but device complexity and power consumption increase due to voltage-controlled oscillators

Engineering Contradiction:

Improveduty cycle accuracyVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent extracts and removes the voltage-controlled oscillator (VCO) from the duty cycle correction system. By eliminating the VCO, the invention significantly reduces device complexity and power consumption while maintaining duty cycle correction functionality through an alternative approach using transistors and correction signals.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the conventional voltage-controlled oscillator mechanism with a transistor-based correction system. Instead of using a VCO to generate correction signals, the invention uses transistors configured as switches controlled by duty cycle error signals, substituting a simpler electronic switching mechanism for the more complex oscillatory system.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Measurement precision

If voltage-controlled oscillators are used for duty cycle correction, then correction capability is achieved, but power consumption increases

Engineering Contradiction:

Improveduty cycle correction capabilityVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent extracts and removes the voltage-controlled oscillator (VCO) from the duty cycle correction system. By eliminating the VCO, the invention significantly reduces device complexity and power consumption while maintaining duty cycle correction functionality through an alternative approach using transistors and correction signals.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs simple transistor switches instead of expensive and power-hungry VCOs. The transistor-based correction mechanism uses low-power switching elements that consume minimal energy compared to the continuous oscillation required by VCOs, achieving correction functionality with much lower power cost.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Measurement precision

If voltage-controlled oscillators are used for duty cycle correction, then correction capability is achieved, but bandwidth impact on clock path increases

Engineering Contradiction:

Improveduty cycle correction capabilityVSAvoidbandwidth impact

Core Design Contradiction:

Measurement precisionVSSpeed

Solution Approach 1:

The patent extracts and removes the voltage-controlled oscillator (VCO) from the duty cycle correction system. By eliminating the VCO, the invention significantly reduces device complexity and power consumption while maintaining duty cycle correction functionality through an alternative approach using transistors and correction signals.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the conventional voltage-controlled oscillator mechanism with a transistor-based correction system. Instead of using a VCO to generate correction signals, the invention uses transistors configured as switches controlled by duty cycle error signals, substituting a simpler electronic switching mechanism for the more complex oscillatory system.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS9882570B1Compact high speed duty cycle corrector

Publication Date: 2018.01.30 MARVELL ASIA PTE LTD

AI summary

Embodiments of the present invention provide techniques for duty cycle correction of clock signals. An input clock signal passes through a pair of output transistors, which provides an output clock signal based on the input clock signal. A duty cycle sensor generates a first correction signal based on the output clock signal. The first correction signal is at least partially opposite of the output clock signal. A duty cycle corrector generates a second correction signal based on the first correction signal. The duty cycle corrector includes two or more transistors for generating the second correction signal. The second correction signal is applied to the output clock signal. There are other embodiments as well.