Lighting Driver for Visible Light Communication

Solution Overview

Problem

Conventional constant current drivers are unable to quickly change their current output, making them unsuitable for visible light communication as the slow changes in current can be detected by occupants, whereas fast current changes are necessary for effective data transmission through LED lighting fixtures.

Innovation Solution

A lighting driver with a processor that generates a compensator signal to control the power provided to an LED light source, enabling fast current changes during visible light communication and slow changes during illumination, utilizing a constant current source circuit that is disabled or enabled based on the operational mode to achieve these changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If a constant current driver with a slow control loop is used to illuminate an area, then flicker is avoided, but the driver is unable to quickly change current output for visible light communication

Engineering Contradiction:

Improvecurrent change speedVSAvoidflicker detection by occupants

Core Design Contradiction:

SpeedVSObject-generated harmful factors

Solution Approach 1:

The driver dynamically switches between two operational modes: constant current mode for illumination and constant voltage mode for visible light communication. This dynamic reconfiguration allows the system to adapt its response characteristics to different operational requirements, achieving fast current changes during VLC while maintaining slow changes during illumination to avoid flicker.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the control parameter from current (during illumination) to voltage (during VLC). By switching the controlled parameter, the driver enables rapid current modulation for communication without the flicker issues associated with slow current control loops during normal illumination operation.

Inventive Principle:

Principle #35Parameter changes

2Productivity

If current changes rapidly for visible light communication, then data transmission is effective, but occupants can detect the change in emitted light

Engineering Contradiction:

Improvedata transmission efficiencyVSAvoiddetection of light changes by occupants

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The driver dynamically switches between two operational modes: constant current mode for illumination and constant voltage mode for visible light communication. This dynamic reconfiguration allows the system to adapt its response characteristics to different operational requirements, achieving fast current changes during VLC while maintaining slow changes during illumination to avoid flicker.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the control parameter from current (during illumination) to voltage (during VLC). By switching the controlled parameter, the driver enables rapid current modulation for communication without the flicker issues associated with slow current control loops during normal illumination operation.

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If a constant current source circuit is enabled during illumination, then stable light output is achieved, but fast current changes are prevented

Engineering Contradiction:

Improvelight output stabilityVSAvoidcurrent response speed

Core Design Contradiction:

Stability of the object's compositionVSSpeed

Solution Approach 1:

The constant current source circuit is selectively disabled during visible light communication operations. By removing this stabilizing element when VLC is performed, the system eliminates the current stability constraint that would otherwise prevent fast current changes needed for effective data transmission through the LED light source.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The driver dynamically switches between two operational modes: constant current mode for illumination and constant voltage mode for visible light communication. This dynamic reconfiguration allows the system to adapt its response characteristics to different operational requirements, achieving fast current changes during VLC while maintaining slow changes during illumination to avoid flicker.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS9848468B1Visible light communication enabling lighting driver

Publication Date: 2017.12.19 SIGNIFY HOLDING BV

AI summary

A lighting driver includes a processor configured to generate a compensator signal based on a first signal during a constant current mode and based on a second signal during a constant voltage mode. The first signal corresponds to a current through an LED light source coupled to an output of the driver, and the second signal corresponds to a voltage at the output. The driver further includes a controller to control, based on the compensator signal, an amount of power provided to the LED light source. The driver also includes a constant current source circuit to be coupled to the LED light source. During the constant current mode, a flow of the current through the constant current source circuit is disabled, and, during the constant voltage mode, disabling the flow of the current through the constant current source circuit disables a flow of the current through the LED light source.