A control circuit includes: an output terminal configured to be coupled to a control terminal of a transistor that has a current path coupled to an inductor; a transconductance amplifier configured to produce a sense current based on a current flowing through the current path of the transistor; and a first capacitor, where the control circuit is configured to: turn on the transistor based on a clock signal, integrate the sense current with an integrating capacitor to generate a first voltage, generate a second voltage across the first capacitor based on a first current, generate a second current based on the second voltage, generate a third voltage based on the second current, turn off the transistor when the first voltage becomes higher than the third voltage; discharge the integrating capacitor when the transistor turns off; and regulate an average output current flowing through the inductor based on the first current.

A lighting apparatus includes a light source, a main controller, a AC-DC converter, a dimmer signal extractor, a dimmer interface circuit and an isolating transformer. The AC-DC converter converts an external AC power to a driving current of a DC power for supplying power to the light source according to a control signal received by the main controller. The dimmer signal extractor generates the control signal supplied to the main controller according to a transformed signal. The dimmer interface circuit is connected to a dimmer. The dimmer is disposed on a wall to be operated by a user to generate a dimmer voltage. The dimmer voltage is converted to a dimmer signal. The isolating transformer has a secondary terminal connecting to the dimmer interface circuit and a first terminal connecting to the dimmer signal extractor.

A lighting apparatus includes a light source, a main controller, a AC-DC converter, a dimmer signal extractor, a dimmer interface circuit and an isolating transformer. The AC-DC converter converts an external AC power to a driving current of a DC power for supplying power to the light source according to a control signal received by the main controller. The dimmer signal extractor generates the control signal supplied to the main controller according to a transformed signal. The dimmer interface circuit is connected to a dimmer. The dimmer is disposed on a wall to be operated by a user to generate a dimmer voltage. The dimmer voltage is converted to a dimmer signal. The isolating transformer has a secondary terminal connecting to the dimmer interface circuit and a first terminal connecting to the dimmer signal extractor.

A control circuit includes: a flip-flop having an output configured to be coupled to a control terminal of a transistor and for producing a first signal; a comparator having an output coupled to an input of the flip-flop, and first and second inputs for receiving first and second voltages, respectively; a transconductance amplifier having an input for receiving a sense voltage indicative of a current flowing through the transistor, and an output coupled to the first input of the comparator; a zero crossing detection (ZCD) circuit having an input configured to be coupled to a first current path terminal of the transistor and to an inductor, where the ZCD circuit is configured to detect a demagnetization time of the inductor and produce a third signal based on the detected demagnetization time; and a reference generator configured to generate the second voltage based on the first and third signals.

A control circuit for a constant-current drive circuit, as well as a constant-current drive circuit are disclosed. The control circuit can obtain output information of the constant-current drive circuit and use it in combination with reference information to determine, according to an output condition corresponding to the current load of the constant-current drive circuit, a time point for the system to enter or exit a rapid drive mode. Therefore, it can be suitably used in various application scenarios to determine a time point for the system to entry into or exit from the rapid start mode. Compared with fast charging for a fixed period of time as used in the prior art, embodiments of the present invention can effectively overcome the problem of easy overshooting or inadequate acceleration during start as found in various applications.

A light source driving method is applied to a light source driving module electrically connected to a light source and a controller. The light source driving module includes a frequency setting module, a driving circuit, and a conversion module. The frequency setting module generates a frequency setting signal according to a switching signal. The driving circuit generates a light source driving signal after receiving the switching signal and a current control signal. The conversion module selectively generates a driving current flowing through the light source in response to the light source driving signal. The driving current increases continuously during a rising duration, and the light source driving signal has a first operating frequency during the rising period. The driving current remains unchanged during a stable duration, and the light source driving signal has a second operating frequency during the stable period.

A dimming regulated power supply module comprising a control circuit, a voltage-stabilizing circuit, a dimming circuit, and an output port, wherein the control circuit converts city power into a supply voltage for supplying power to a LED light string through the output port, wherein the voltage-stabilizing circuit senses an internal voltage of the control circuit to generate a first voltage and a second voltage, and supplies power to a single-chip microcomputer in the dimming circuit after stabilizing the second voltage, wherein the voltage-stabilizing circuit outputs the first voltage to set the voltage range of the dimming circuit, wherein the output port transmits the dimming signal output by a dimmer to the dimming circuit, and wherein the dimming circuit generates a corresponding pulse-width modulation signal, wherein the control circuit controls the supply current according to the pulse-width modulation signal, thereby controls the brightness of the LED light string through the output port.

A dimming regulated power supply module comprising a control circuit, a voltage-stabilizing circuit, a dimming circuit, and an output port, wherein the control circuit converts city power into a supply voltage for supplying power to a LED light string through the output port, wherein the voltage-stabilizing circuit senses an internal voltage of the control circuit to generate a first voltage and a second voltage, and supplies power to a single-chip microcomputer in the dimming circuit after stabilizing the second voltage, wherein the voltage-stabilizing circuit outputs the first voltage to set the voltage range of the dimming circuit, wherein the output port transmits the dimming signal output by a dimmer to the dimming circuit, and wherein the dimming circuit generates a corresponding pulse-width modulation signal, wherein the control circuit controls the supply current according to the pulse-width modulation signal, thereby controls the brightness of the LED light string through the output port.

A control circuit includes an output terminal configured to be coupled to a control terminal of a transistor that has a current path coupled to an inductor; a transconductance amplifier configured to produce a sense current based on a current flowing through the current path of the transistor; and a first capacitor. The control circuit is configured to turn on the transistor based on a clock signal, integrate the sense current with an integrating capacitor to generate a first voltage, generate a second voltage across the first capacitor based on a first current, generate a second current based on the second voltage, generate a third voltage based on the second current, turn off the transistor when the first voltage becomes higher than the third voltage; discharge the integrating capacitor when the transistor turns off; and regulate an average output current flowing through the inductor based on the first current.

A dimming regulated power supply module comprising a control circuit, a voltage-stabilizing circuit, a dimming circuit, and an output port, wherein the control circuit converts city power into a supply voltage for supplying power to a LED light string through the output port, wherein the voltage-stabilizing circuit senses an internal voltage of the control circuit to generate a first voltage and a second voltage, and supplies power to a single-chip microcomputer in the dimming circuit after stabilizing the second voltage, wherein the voltage-stabilizing circuit outputs the first voltage to set the voltage range of the dimming circuit, wherein the output port transmits the dimming signal output by a dimmer to the dimming circuit, and wherein the dimming circuit generates a corresponding pulse-width modulation signal, wherein the control circuit controls the supply current according to the pulse-width modulation signal, thereby controls the brightness of the LED light string through the output port.