LED Supply Voltage Feedback Control for Headroom-Based Power Saving

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing LED systems waste energy when the supply voltage exceeds the necessary level for illumination, leading to inefficiency and increased energy consumption.

Innovation Solution

A system that adjusts the LED supply voltage by monitoring the headroom voltage and using comparators to generate feedback signals to a power converter, reducing the voltage when it exceeds a threshold and increasing it when it falls below another threshold, thereby optimizing energy use.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the LED supply voltage is increased to ensure adequate illumination, then the illumination reliability is improved, but the energy consumption increases

Engineering Contradiction:
Improveillumination reliabilityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements dynamic voltage adjustment by continuously monitoring the headroom voltage and comparing it to threshold values. The system dynamically changes the LED supply voltage based on real-time conditions, switching between different voltage levels to maintain adequate illumination while minimizing energy consumption when full voltage is not required.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent employs a feedback mechanism where the headroom voltage is monitored and fed back to the voltage adjustment circuitry. The comparator compares the headroom voltage to a threshold, and based on this feedback, the system adjusts the LED supply voltage accordingly, creating a closed-loop control system that balances illumination reliability with energy efficiency.

Inventive Principle:
Principle #23Feedback

2Stability of the object's composition

If the LED supply voltage is maintained at a high level to ensure consistent performance, then the illumination consistency is improved, but the energy waste increases

Engineering Contradiction:
Improveillumination consistencyVSAvoidenergy waste
Core Design Contradiction:
Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The system dynamically adjusts the LED supply voltage based on real-time headroom voltage measurements rather than maintaining a static high voltage. This dynamic approach ensures illumination consistency when needed while avoiding energy waste during periods when lower voltage suffices, directly resolving the contradiction between consistency and energy waste.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the voltage parameter dynamically based on operating conditions. By monitoring headroom voltage and comparing it to thresholds, the system adjusts the supply voltage parameter to maintain illumination consistency only when necessary, reducing energy waste during normal operating conditions where full voltage is not required.

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If a simple voltage regulation system is used, then the device complexity is reduced, but the energy optimization capability is insufficient

Engineering Contradiction:
Improvesystem complexityVSAvoidenergy optimization
Core Design Contradiction:
Device complexityVSUse of energy by moving object

Solution Approach 1:

The patent implements a feedback-based voltage adjustment system that monitors headroom voltage and automatically adjusts the LED supply voltage. This feedback mechanism provides effective energy optimization without requiring complex artificial intelligence or sophisticated control algorithms, achieving a balance between system complexity and energy optimization capability through straightforward voltage monitoring and adjustment.

Inventive Principle:
Principle #23Feedback

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 system enhances LED efficiency and reduces energy consumption by dynamically adjusting the supply voltage based on actual illumination needs, ensuring optimal performance while minimizing power usage.

Implementation Method 1

a first comparator, which can be configured to compare a headroom voltage of a current-sinking LED driver, such as measured between a current-sinking LED driver node and a reference potential node, to a first threshold value and can generate a first comparator output as a result of the comparison

Methodology Applied
Scientific EffectVoltage comparison:

Implementation Method 2

Light-emitting diodes (LEDs) can be semiconductor devices that can convert electrical energy into light through electroluminescence

Methodology Applied
Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentEP4672865A1Light-emitting diode supply voltage system
Publication Date: 2025.12.31 ANALOG DEVICES INT UNLTD CO
  • EP4672865A1 patent drawingFigure 1
  • EP4672865A1 patent drawingFigure 2
  • EP4672865A1 patent drawingFigure 3

AI summary

A light-emitting diode (LED) supply voltage system for adjusting an LED supply voltage can include an LED supply voltage control circuit. The LED supply voltage control circuit can include a first comparator, which can be configured to compare a headroom voltage of a current-sinking LED driver, such as measured between a current-sinking LED driver node and a reference potential node, to a first threshold value and can generate a first comparator output as a result of the comparison. The LED supply voltage system can also include an LED supply voltage control circuit, which can include comparator processing circuitry, which can be configured to receive the first comparator output and generate a feedback signal to a power converter based on the received first comparator output. This can include to recurrently, adjust the feedback signal such that the power converter reduces the LED supply voltage by a specified voltage decrement value when the first comparator output indicates that the headroom voltage can be above the first threshold value.