Drive circuit realizing constant current of two paths of LEDs by utilizing capacitors

Abstract

The invention discloses a drive circuit realizing the constant current of two paths of LEDs by utilizing capacitors, which comprises a high-frequency pulse AD power supply, a blocking capacitor, a first diode, a second diode, a first inductor, a second inductor, a first filter capacitor, a second filter capacitor and two paths of LED loads. The drive circuit has the advantages that: 1, the constant current of the two paths of LED loads is realized by a primary conversion circuit, cost is low, no additional control circuit is required and reliability is high; 2, current equalization efficiencyis high and current equalization is not influenced by a voltage difference between the LED loads; and 3, the efficiency of the current equalization realized by the blocking capacitor is high, and theloss of the current equalization is relatively lower even though the voltage difference of the two paths of LEDs is relatively greater.

Description

technical field [0001] The invention relates to a driving circuit for realizing constant current of two LEDs by using capacitance. Specifically, it should be a circuit that balances the load current of two LEDs through capacitors. Background technique [0002] For the application of LED multi-channel constant current control driver, the most commonly used solutions are: 1. Constant voltage module + multi-channel non-isolated DC / DC constant current circuit (such as BUCK circuit); 2. Voltage adjustable voltage regulator module + multi-line Sexually adjust the constant current circuit. [0003] For the first option, refer to figure 1 , the output of the constant voltage module is used as the input of multiple constant current circuits, and each constant current circuit is independently controlled by constant current, which can easily ensure the current sharing of multiple output currents. However, because the voltage of the constant voltage module and the voltage of the LED ...

AI Technical Summary

Problems solved by technology

Although the circuit cost of this solution is low and the current sharing of each LED is good, short circuit is a common failure mode of LEDs. When the voltage difference of multiple LEDs is relatively large, the power consumption of the linear adjustment tube is very large, which makes the LED driver seriously heat.

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