A system is created for an efficient dimming LED lighting system, and comprising a voltage source, an electronic switch controlled by a pulse width modulation, PWM, driving signal and an LED lighting module connected in series. The LED comprises an LED group and a constant current drive circuit to drive a constant current through the LED group. The voltage source and a bypass branch, which is connected in parallel with the electronic switch, is adapted such that when the electronic switch is open, a power delivered to the constant current drive circuit is sufficient to maintain operation of the constant current drive circuit, ensuring capability for a deep dimming

A system is created for an efficient dimming LED lighting system, and comprising a voltage source, an electronic switch controlled by a pulse width modulation, PWM, driving signal and an LED lighting module connected in series. The LED comprises an LED group and a constant current drive circuit to drive a constant current through the LED group. The voltage source and a bypass branch, which is connected in parallel with the electronic switch, is adapted such that when the electronic switch is open, a power delivered to the constant current drive circuit is sufficient to maintain operation of the constant current drive circuit, ensuring capability for a deep dimming

An LED lamp and it power source module are provided. The LED lamp includes an LED module and a power source module. The power source module includes two rectifying circuits, a filtering capacitor, a plurality of fuses, two filament-simulating circuits, and a discharge device. Each of the filament-simulating circuits is configured to allow a current to flow from one pin to the other pin via the corresponding first and second filament-simulating circuits during a pre-heat process executed by a ballast.

A lighting apparatus includes a light source, a driver circuit, a high side control module and a low side control module. The light source includes a LED module. The driver circuit includes a high side circuit and a low side circuit for generating a driving current to the LED module. The high side control module for controls the high side circuit. The high side control module includes a voltage stabilizer and a current trigger. The voltage stabilizer is placed on a voltage input of a high side. The current trigger is connected to an output of the voltage stabilizer. The low side control module controls the low side circuit. The low side control module includes a buck converter, a constant current trigger, and a low side constant current source. The buck converter is connected to a second input of the current trigger.

A lighting apparatus includes a light source, a driver circuit, a high side control module and a low side control module. The light source includes a LED module. The driver circuit includes a high side circuit and a low side circuit for generating a driving current to the LED module. The high side control module for controls the high side circuit. The high side control module includes a voltage stabilizer and a current trigger. The voltage stabilizer is placed on a voltage input of a high side. The current trigger is connected to an output of the voltage stabilizer. The low side control module controls the low side circuit. The low side control module includes a buck converter, a constant current trigger, and a low side constant current source. The buck converter is connected to a second input of the current trigger.

In an embodiment, a control circuit includes: an output terminal configured to be coupled to a control terminal of a transistor that is coupled to an inductor; a logic circuit configured to control the transistor using a first signal; a zero crossing detection circuit configured to generate a freewheeling signal indicative of a demagnetization of the inductor; a comparator having first and second inputs configured to receive a sense voltage indicative of a current flowing through the transistor and a reference voltage, respectively, and an output configured to cause the logic circuit to dessert the first signal; and a reference generator configured to generate the reference voltage and including: a current generator, a capacitor and a resistor coupled to the output of the reference generator, and a switch coupled in series with the resistor and configured to be controlled based on the first signal and the freewheeling signal.

In an embodiment, a control circuit includes: an output terminal configured to be coupled to a control terminal of a transistor that is coupled to an inductor; a logic circuit configured to control the transistor using a first signal; a zero crossing detection circuit configured to generate a freewheeling signal indicative of a demagnetization of the inductor; a comparator having first and second inputs configured to receive a sense voltage indicative of a current flowing through the transistor and a reference voltage, respectively, and an output configured to cause the logic circuit to dessert the first signal; and a reference generator configured to generate the reference voltage and including: a current generator, a capacitor and a resistor coupled to the output of the reference generator, and a switch coupled in series with the resistor and configured to be controlled based on the first signal and the freewheeling signal.

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 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.

The present disclosure relates to a dimmable LED lamp illumination system. The dimmable LED lamp illumination system includes: a dimmer and an LED lamp. The dimmer is connected in series between a power input end and the LED lamp, and is used for loading a digital dimming signal onto a power signal, so as to generate a dimming power signal. The LED lamp receives the dimming power signal, demodulates the digital dimming signal, and adjusts the brightness of the LED lamp based on the demodulated digital dimming signal. By using the dimmable LED lamp illumination system of the present disclosure, the deployment of a dimming system is simpler, and the transmission of a digital dimming signal is more stable.