LIGHT-EMITTING DIODE LIGHT SOURCE Russian patent published in 2017 - IPC H05B33/08 

FIELD: physics.

SUBSTANCE: LED light source comprises a rectifier having the rectifier input terminals for connection to the corresponding output terminals of the brightness control with the cut-off phase at the trailing edge. The rectifier input terminals are connected to the main power supply, and having the rectifier output terminals, the first circuit of shunt resistance connecting the rectifier output terminals, the serial arrangement having a unidirectional element and a capacitive means connecting the rectifier output terminals, the converter circuit, the input terminals of which are connected to the respective sides of the capacitive means, and the output terminals are connected to the LED load for generating current through the LED load depending on the brightness control signal, from the voltage present at the capacitive means, the brightness control circuit for generating the brightness control signal depending on the adjustable phase angle for brightness control with the cut-off phase and brightness control signaling to the brightness control input of the converter circuit. The brightness control circuit comprises: a gradient detecting circuit for determining the voltage gradient on the capacitive means and for determining the first phase angle value as an adjustable phase angle, for which the gradient is negative, when the phase angle is less than 90 degrees, a signal generating circuit for generating a sinusoidal signal, which is the voltage of the main power supply, a circuit for activating the first shunt resistance, when the phase angle is 90 degrees, and for disabling the first shunt resistance, when the adjustable angle phase is determined, when the adjustable phase angle is more than 90 degrees, a deviation detection circuit for detecting the voltage deviation at the rectifier output terminals from the sinusoidal signal, for comparing the deviation voltage with the reference voltage and for determining as an adjustable phase angle of the phase angle value, for which the deviation voltage is more than or equal to the reference voltage, when the phase angle is at the range of 90 to 180 degrees.

EFFECT: providing LED light source, brightness of which can be adjusted via the brightness control with the cut-off phase at the trailing edge, with the exception of breaks and non-linearities in the relationship between the brightness control signal and the output light.

8 cl, 5 dwg