LED Driver Dimmed Input Sense Circuit for Flicker Elimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional LED drivers experience inconsistent light output and dimming levels due to power delivery issues, leading to flickering and instability, and require inconvenient configuration and replacement processes.
Innovation Solution
An LED driver circuit that uses a dimmed AC input signal to generate a stable output signal for powering LEDs, incorporating a dimmed input sense circuit, microcontroller, and power supply circuit to detect and adjust the duty cycle, ensuring consistent dimming and allowing for easy configuration through a removable PCB with stored dimming parameters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If traditional phase controlled two-wire LED drivers use raw power delivery from dimmed AC input signal, then the device complexity is reduced and manufacturing cost is lowered, but the light output consistency and dimming level stability deteriorate
Solution Approach 1:
The patent introduces a dimmed input sense circuit as an intermediary between the dimmed AC input signal and the power delivery circuit. This sense circuit detects the incoming duty cycle and provides this information to a microcontroller, which then generates an output duty cycle to control the LED driver. This intermediary measurement and control mechanism ensures consistent light output while maintaining reasonable device complexity.
2Loss of energy
If traditional LED drivers directly translate incoming RMS power to outbound power delivery, then the power conversion efficiency is improved and energy loss is reduced, but the dimming linearity and brightness control accuracy deteriorate
Solution Approach 1:
The patent implements a feedback mechanism where the dimmed input sense circuit continuously monitors the incoming duty cycle of the dimmed AC input signal. The microcontroller receives this feedback information and adjusts the output duty cycle accordingly to achieve the desired dimming level. This closed-loop control ensures accurate brightness control while maintaining energy efficiency by only processing the necessary power levels.
3Use of energy by moving object
If traditional drivers operate at very low dimming levels with noisy phase controlled signals, then the energy consumption is reduced and energy saving opportunities increase, but the power supply stability and light output reliability deteriorate
Solution Approach 1:
The patent applies preliminary action by having the dimmed input sense circuit detect and measure the incoming duty cycle before the power delivery stage. The microcontroller processes this information in advance and generates the appropriate output duty cycle signal. This preliminary detection and processing ensures that even at very low dimming levels, the power supply remains stable and the LED output is reliable, avoiding the instability caused by directly using noisy low-power signals.
Data Source
AI summary
Devices, systems, software, and methods for control of light emitting diodes (LEDs) via an LED driver circuit that receives a dimmed AC input signal from a dimmer and generates an output signal to power and dim an LED element. The LED driver circuit comprises a dimmed input sense circuit, a microcontroller, and a power supply circuit. The power supply circuit generates a power supply from the dimmed AC input signal for powering the LED driver circuit. The dimmed input sense circuit detects an incoming duty cycle (Din) of the dimmed AC input signal. The microcontroller stores one or more dimming level parameters, receives the detected incoming duty cycle (Din) from the dimmed input sense circuit, and generates an output duty cycle (Dout) based on the detected incoming duty cycle (Din) and the one or more dimming level parameters. The LED driver circuit generates the output signal using the generated output duty cycle (Dout) for powering the LED element at a generated dimming level.