LED Driving Device Dynamic Switching for Power Optimization
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Solution Overview
Problem
Existing LED driving devices require higher voltage sources to power multiple LEDs connected in series, leading to increased power consumption and unstable current, which affects LED brightness.
Innovation Solution
An LED driving device with (N-1) switch units, a current source, and a detection unit, where the control unit dynamically controls the switch units based on voltage references to optimize current distribution across N LED strings connected in series, reducing power consumption and improving illumination quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If multiple LEDs are connected in series to increase brightness, then illumination intensity is improved, but higher voltage is required leading to increased power consumption
Solution Approach 1:
The patent applies dynamic switching by controlling switch units to connect different numbers of LED strings in series based on detected voltage levels. The system transitions between different series configurations dynamically, allowing LEDs to operate at optimal brightness without requiring a continuously high voltage source, thus reducing overall power consumption.
Solution Approach 2:
The system changes the electrical parameters (voltage and current distribution) by detecting the voltage level and switching between different LED string configurations. When voltage is sufficient, more LED strings are connected in series for higher brightness; when voltage is low, fewer strings are connected to maintain stable operation, effectively adapting to varying power conditions.
2Illumination intensity
If higher voltage is supplied to drive series-connected LEDs, then illumination intensity is improved, but current stability deteriorates affecting LED brightness
Solution Approach 1:
The patent implements a feedback mechanism where the detection unit continuously monitors the voltage level, and the control unit adjusts the switching state of the switch units based on this feedback. This closed-loop control ensures that the current through the LEDs remains stable by adapting the series configuration to match the available voltage, preventing current fluctuations that would affect brightness consistency.
Solution Approach 2:
The system dynamically adjusts the number of LED strings connected in series based on real-time voltage detection. This dynamic reconfiguration allows the system to maintain optimal current stability across varying voltage conditions, ensuring consistent LED brightness without requiring a perfectly stable high-voltage supply.
3Device complexity
If a fixed voltage source is used to drive LEDs, then device complexity is reduced, but adaptability to varying voltage conditions deteriorates
Solution Approach 1:
The patent introduces dynamic switching capability with switch units that can reconfigure the LED strings based on detected voltage levels. This adds adaptability to the system without significantly increasing complexity, as the switching mechanism uses simple control logic based on voltage threshold detection, allowing the same device to handle varying voltage conditions effectively.
Solution Approach 2:
The driving device achieves multi-functionality by being able to operate with different voltage levels and configure different numbers of LED strings in series or parallel. This universal design allows a single device to adapt to various power supply conditions and LED arrangements, enhancing versatility without requiring multiple dedicated circuits for each scenario.
Data Source
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AI summary
A LED driving device adapted to driving N LED strings connected in series is provided. N is a positive integer greater than 1. The LED driving device includes (N-1) switch units, a current source, a detection unit and a control unit. The ith switch unit electrically connects to the (i+1) LED string in parallel or to the ith LED string in parallel, and 0 < i ≦ (N-1). The current source supplies a driving current to drive the N LED strings. The detection unit outputs a detection signal according to a voltage of the current source, a first reference voltage and a second reference voltage. The control unit outputs a plurality of first control signals according to the detection signal to dynamically control an amount of the (N-1) switch units turned on.