Shared Power Converter Circuit for RGB LED Backlight Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
RGB LED backlights in LCD televisions require different turn-on voltages, leading to inefficient power consumption as existing solutions either increase the size and cost of printed-circuit boards with additional components or consume high power with complex transformer and inductor setups.
Innovation Solution
A power converter circuit that operates in boost, energy recycling, silence, and energy transfer modes, using an active diode to manage voltage and current flow efficiently across different LEDs, storing energy in a capacitor and reusing it to drive LEDs of other colors, thereby reducing overall power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If three power converters are used for each R, G, and B LED, then power consumption is optimized for each LED, but the size and cost of printed-circuit boards increase due to additional components
Solution Approach 1:
The patent combines three separate power converters into a single shared power converter that serves all R, G, and B LEDs. This is achieved by using a single converter with a controller that selectively connects it to different LED groups through switching elements, thereby reducing the number of inductors and external components while maintaining optimized power delivery to each LED type.
Solution Approach 2:
The single power converter is designed to perform multiple functions by sequentially or selectively powering different LED groups (R, G, and B). The converter acts as a universal power source that can be dynamically allocated to different loads, eliminating the need for dedicated converters for each LED type while still providing optimized power consumption for each.
2Use of energy by moving object
If a parallel driving structure with complex transformer and two inductors is used, then power consumption is reduced, but device complexity increases
Solution Approach 1:
The patent merges the functions of the complex transformer and multiple inductors into a simpler single-inductor architecture. The shared power converter uses one inductor along with switching elements to achieve the same power delivery and isolation functions that previously required a complex transformer and two inductors, thereby reducing component count and circuit complexity while maintaining power efficiency.
3Device complexity
If a single converter with PWM current controller is used, then device complexity is reduced, but power consumption increases due to the PWM controller
Solution Approach 1:
The patent extracts and removes the PWM current controller from the power converter system. Instead of using a PWM controller that consumes significant power, the invention employs a controller that uses switching elements to directly connect the shared power converter to different LED groups, eliminating the need for PWM modulation and its associated power consumption while maintaining simple device architecture.
4Device complexity
If a same driving voltage is used for all R, G, and B LEDs, then device complexity is minimized, but power consumption becomes inefficient due to different turn-on voltages
Solution Approach 1:
The patent applies local quality by providing different driving voltages to different LED groups (R, G, and B) using a single shared power converter. The controller selectively connects the converter to specific LED groups based on their required turn-on voltages, allowing each LED type to receive the appropriate voltage level for efficient operation while maintaining overall system simplicity.
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
The circuit achieves a 10% improvement in efficiency by optimizing power usage across RGB LEDs, reducing the need for additional components and minimizing power wastage, while maintaining stable voltage and current delivery.
Implementation Method 1
a first capacitive device, coupled between a first node and a reference node
Implementation Method 2
a first diode device having an anode coupled to an input node and a cathode coupled to the first node
Implementation Method 3
a power converter including an inductive device between a second node and a third node
Data Source
AI summary
In at least one embedment, a circuit includes an input node, an energy node, a reference node, an output node, a first capacitive device, a first diode device, and a power converter. The first capacitive device is coupled between the energy node and the reference node. The first diode device has an anode coupled to the input node and a cathode coupled to the energy node. The power converter is coupled between the energy node and the output node.