A variable light distribution light source includes an array-type light-emitting device. The array-type light-emitting device includes a power supply terminal and multiple pixel circuits electrically coupled and spatially arranged in a matrix. A power supply circuit includes a power supply unit that supplies electric power to the array-type light-emitting device. An output of a DC/DC converter is coupled to the power supply terminal VDD of the array-type light-emitting device via an output terminal. A voltage setting circuit generates a controllable correction voltage. A feedback circuit generates a feedback voltage based on the correction voltage and the control target voltage that corresponds to the output voltage of the DC/DC converter, and supplies the feedback voltage to a feedback pin of a converter controller.

A variable light distribution light source includes an array-type light-emitting device. The array-type light-emitting device includes a power supply terminal and multiple pixel circuits electrically coupled and spatially arranged in a matrix. A power supply circuit includes a power supply unit that supplies electric power to the array-type light-emitting device. An output of a DC/DC converter is coupled to the power supply terminal VDD of the array-type light-emitting device via an output terminal. A voltage setting circuit generates a controllable correction voltage. A feedback circuit generates a feedback voltage based on the correction voltage and the control target voltage that corresponds to the output voltage of the DC/DC converter, and supplies the feedback voltage to a feedback pin of a converter controller.

A leakage protection circuit and a dimming drive circuit are provided. A leakage detection circuit is configured to detect whether leakage occurs between two input terminals that receive an external signal. When leakage occurs, leakage protection measures are taken. A pulse generation circuit receives the sampling signal characterizing the voltage between the two input terminals to compare the sampling signal with two thresholds to control a detection path of the leakage detection circuit to be turned on or off according to a comparison result. The leakage detection path is enabled to be turned on twice by setting two pulse signals in a power frequency period, which can consider the leakage detection of the front-edge phase-cutting dimming and rear-edge phase-cutting dimming of the dimming drive circuit and has a wide range of applications.

A leakage protection circuit and a dimming drive circuit are provided. A leakage detection circuit is configured to detect whether leakage occurs between two input terminals that receive an external signal. When leakage occurs, leakage protection measures are taken. A pulse generation circuit receives the sampling signal characterizing the voltage between the two input terminals to compare the sampling signal with two thresholds to control a detection path of the leakage detection circuit to be turned on or off according to a comparison result. The leakage detection path is enabled to be turned on twice by setting two pulse signals in a power frequency period, which can consider the leakage detection of the front-edge phase-cutting dimming and rear-edge phase-cutting dimming of the dimming drive circuit and has a wide range of applications.

A Light Emitting Diode, LED, based lighting device arranged for connection to an Alternating Current, AC, mains supply, comprising a zero-crossing detection module arranged for detecting a zero-crossing in an AC voltage supplied by said AC mains supply, a detection pulse module arranged for providing a detection pulse based on said detected zero-crossing, a human body detection module arranged for determining a current drawn from said AC mains supply during said provided detection pulse, and for determining presence of a human body based on said determined current, wherein said detection pulse module is arranged for providing said detection pulse during a rising, positive, edge of said AC voltage.

A Light Emitting Diode, LED, based lighting device arranged for connection to an Alternating Current, AC, mains supply, comprising a zero-crossing detection module arranged for detecting a zero-crossing in an AC voltage supplied by said AC mains supply, a detection pulse module arranged for providing a detection pulse based on said detected zero-crossing, a human body detection module arranged for determining a current drawn from said AC mains supply during said provided detection pulse, and for determining presence of a human body based on said determined current, wherein said detection pulse module is arranged for providing said detection pulse during a rising, positive, edge of said AC voltage.

The present disclosure provides a light emitting element driving device. The light emitting element driving device includes a constant current circuit and a current detection unit. The constant current circuit includes: a first transistor including a first end, a second end and a control end connected to an external terminal; a current setting resistance connected to the second end of the first transistor; and a drive amplifier including a first input end connected to a first node to which the first transistor and the current setting resistance are connected, a second input end to which a current set voltage is applied, and an output end connected to the control end of the first transistor. The current detection unit generates a current detection signal based on a feedback voltage generated in the first node.

The present disclosure provides a light emitting element driving device. The light emitting element driving device includes a constant current circuit and a current detection unit. The constant current circuit includes: a first transistor including a first end, a second end and a control end connected to an external terminal; a current setting resistance connected to the second end of the first transistor; and a drive amplifier including a first input end connected to a first node to which the first transistor and the current setting resistance are connected, a second input end to which a current set voltage is applied, and an output end connected to the control end of the first transistor. The current detection unit generates a current detection signal based on a feedback voltage generated in the first node.

A light-emitting diode (LED) tube lamp and an electric leakage protection circuit are provided. The LED tube lamp. The LED tube lamp includes a leakage detecting module and a driving module comprising a Type A+B driving circuit. The leakage detecting module is connected with a power supply. The driving module is electrically connected with the leakage detecting module. The leakage detecting module detects a signal related to the output current of the power supply, and when the signal related to the output current of the power supply exceeds a reference signal, the leakage detecting module limits the current on a power loop connected to the power supply by periodically turning off a switch electrically connected to the power loop in series.

A light-emitting diode (LED) tube lamp and an electric leakage protection circuit are provided. The LED tube lamp. The LED tube lamp includes a leakage detecting module and a driving module comprising a Type A+B driving circuit. The leakage detecting module is connected with a power supply. The driving module is electrically connected with the leakage detecting module. The leakage detecting module detects a signal related to the output current of the power supply, and when the signal related to the output current of the power supply exceeds a reference signal, the leakage detecting module limits the current on a power loop connected to the power supply by periodically turning off a switch electrically connected to the power loop in series.