Abstract: Disclosed is an alternating current dimming drive circuit for an LED, comprising a rectification unit and N stages of LED direct current drive circuits. In the ith stage of LED direct current drive circuit, a first end of the ith voltage sampling unit and an input end of the ith LED light source module directly or indirectly receive the output voltage of the rectification unit; a voltage division end of the ith voltage sampling unit is connected to a second input end of the ith switch unit; and a first input end of the ith switch unit is connected to an output end of the ith LED light source module, and an output end of the ith switch unit, a second end of the ith voltage sampling unit and a second output end of the rectification unit are grounded. When the ith switch unit is switched on, the first to the ith LED light source modules emit light.

Abstract: Disclosed are an alternating current rectifying circuit and an alternating current rectifying method for driving an LED module.

Abstract: Disclosed are an alternating current rectifying circuit and an alternating current rectifying method for driving an LED module.

Abstract: The present disclosure discloses a multipath current source switching device, including a switching control unit, N current paths, and N loads. Each current path is formed by a constant current source circuit and a switching circuit. One terminal of a first load is coupled to a load power supply, and the other terminal of the first load is coupled to an output terminal of a constant current source circuit of a first current path and one terminal of a second load; one terminal of an ith load is coupled to the other terminal of an (i?1)th load and an output terminal of a constant current source circuit of an ith current path; and the switching control unit controls an output current of a corresponding constant current source circuit through a corresponding switching circuit.

Abstract: Disclosed is an alternating current dimming drive circuit for an LED, comprising a rectification unit and N stages of LED direct current drive circuits. In the ith stage of LED direct current drive circuit, a first end of the ith voltage sampling unit and an input end of the ith LED light source module directly or indirectly receive the output voltage of the rectification unit; a voltage division end of the ith voltage sampling unit is connected to a second input end of the ith switch unit; and a first input end of the ith switch unit is connected to an output end of the ith LED light source module, and an output end of the ith switch unit, a second end of the ith voltage sampling unit and a second output end of the rectification unit are grounded. When the ith switch unit is switched on, the first to the ith LED light source modules emit light.

Abstract: The present invention discloses a white LED light emitting device driven directly by constant current in manner of being supplied with alternating current. N parallel branches, consisting of LED modules and constant current units which are in series connection with the LED modules, are connected to an output terminal of a rectification circuit, and by setting the current value, the turning-off voltage, and the turning-on voltage of the constant current unit of each branch, the periodic flickers generated due to changes in the voltage of the alternating current can be avoided. Because the current of each branch is constant, the changes in junction temperatures do not result in the current changing in LED, and the reliability is improved. Along with the increase of the number of the branches, the driving current waveform approximates a sine wave, and the power factor and the efficiency of the light emitting device are improved.