Direct-current light emitting diode (LED) constant-current driving circuit and LED lamp

Abstract

The invention relates to a direct-current light emitting diode (LED) constant-current driving circuit. The constant-current driving circuit comprises a constant current module, wherein the constant current module comprises a constant current chip, an energy storage inductor, a diode, a first energy storage capacitor and a sampling resistor; an input end of the constant current module receives an electrical signal which is input by a power supply; one end of the first energy storage capacitor is connected to the ground, and the other end of the first energy storage capacitor is connected to a cathode of the diode; an anode of the diode is connected with one end of the energy storage inductor and is connected to the ground through a pin of the constant current chip, and the other end of the energy storage inductor is provided with the input end of the constant current module; one end of the sampling resistor is connected to the cathode of an LED light source, and the other end of the sampling resistor is connected to the ground; and the constant current chip acquires voltage of the sampling resistor and adjusts the ratio of turn-on time to turn-off time of the pin according to the voltage of the sampling resistor. The invention also relates to an LED lamp. The direct-current LED constant-current driving circuit and the LED lamp can adjust the ratio of the turn-on time to the turn-off time of the pin which is connected between the anode of the diode and the energy storage inductor according to the voltage of the cathode of the LED light source, which is acquired by sampling, and are suitable for power supplies with a wide voltage input range.

Description

【Technical field】 [0001] The invention relates to the field of electric lighting, in particular to a DC type LED constant current drive circuit, and also relates to an LED lamp. 【Background technique】 [0002] As a new type of light source, LED (Light Emitting Diode) has the characteristics of energy saving, environmental protection and high efficiency. The technology has been mature and applied in various fields. LEDs are widely used as lighting sources, and various DC LED constant current drive circuits have emerged. As a constant current load, LED itself has strict requirements on the working voltage, too high or too low voltage will cause the LED to work abnormally, so the power supply quality of the power supply voltage directly affects the reliability of the LED. At present, constant current technology is used to drive LEDs in AC and DC low-voltage power supply places. It has the advantages of low power consumption, high efficiency, small volume per unit power, and li...

AI Technical Summary

Problems solved by technology

At present, constant current technology is used to drive LEDs in AC and DC low-voltage power supply places. It has the advantages of low power consumption, high efficiency, small volume per unit power, and light weight. However, the input voltage range is relatively narrow. When the input voltage is too high When it is low, the working current of the LED will be reduced, the output luminous flux will be reduced, the LED cannot work at full load, and the light of the LED lamp is dim, which brings serious inconvenience to the user.

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