A lighting arrangement such as a LED lamp comprises a light source and associated current driver, or a set of at least two parallel light sources and associated current drivers, supplied by a DC voltage from a voltage-regulated power converter. A feedback circuit provides a temperature-dependent control input to a control loop of the power converter, such that the DC voltage is adjusted in dependence on a sensed temperature. In this way, the voltage headroom required can be reduced, and efficiency gains are made.

A constant current LED driver, for controlling a current flowing through a LED, comprising: an adjusting circuit, configured to generate a first current and a first adjusting signal; a feedback circuit, controlled by an output signal, to generate a feedback voltage according to the first current; an operation amplifier, configured to generate the output signal according to the LED voltage and the feedback voltage; and an edge adjusting circuit, configured to adjust a first type of edges or a second type of edges of the first adjusting signal to generate a second adjusting signal, wherein the LED is controlled by the second adjusting signal. The above-mentioned constant current LED driver can be used as a current control circuit for controlling a current flowing through a target device.

A constant current LED driver, for controlling a current flowing through a LED, comprising: an adjusting circuit, configured to generate a first current and a first adjusting signal; a feedback circuit, controlled by an output signal, to generate a feedback voltage according to the first current; an operation amplifier, configured to generate the output signal according to the LED voltage and the feedback voltage; and an edge adjusting circuit, configured to adjust a first type of edges or a second type of edges of the first adjusting signal to generate a second adjusting signal, wherein the LED is controlled by the second adjusting signal. The above-mentioned constant current LED driver can be used as a current control circuit for controlling a current flowing through a target device.

A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage V.sub.OUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

A device includes a voltage regulator, circuits, and a current bus. Each of the circuits includes at least one LED driver. The voltage regulator supplies electrical energy to a plurality of LED groups. Each of the circuits includes a voltage measuring circuit for detecting voltage drops across the LED drivers. The LED drivers set the currents through the LED groups. Each of the circuits includes a local controller. The local controller withdraws a current from the control bus in dependence on the detected voltage drops of the LED drivers included in the circuit. A bias current source injects a bias current into the control bus. The control bus sums the currents in the current bus. The output of the regulator is controlled based on the summed current.

A device includes a voltage regulator, circuits, and a current bus. Each of the circuits includes at least one LED driver. The voltage regulator supplies electrical energy to a plurality of LED groups. Each of the circuits includes a voltage measuring circuit for detecting voltage drops across the LED drivers. The LED drivers set the currents through the LED groups. Each of the circuits includes a local controller. The local controller withdraws a current from the control bus in dependence on the detected voltage drops of the LED drivers included in the circuit. A bias current source injects a bias current into the control bus. The control bus sums the currents in the current bus. The output of the regulator is controlled based on the summed current.

An intelligent lighting device control system includes a plurality of lighting devices and an intelligent lighting device controller. The intelligent lighting device controller includes a detecting module, a main power source module and an intelligent control module. The detecting module has a detecting circuit. The main power source module includes a plurality of first electrode connectors and a common electrode connector. The first electrode connectors are connected to the detecting circuit and connected to the first electrodes of the lighting devices via the detecting circuit. The common second electrode connector is connected to the second electrodes of the lighting devices and outputs an electricity signal to drive the lighting devices, such that the detecting circuit generates a plurality of detecting signals. The intelligent control module generates a feedback signal according to the detecting signals and the main power source module adjusts the electricity signal according to the feedback signal.

A lighting circuit turns on a plurality of semiconductor light sources. Multiple current sources are each coupled to a corresponding semiconductor light source. A switching converter supplies a driving voltage V.sub.OUT across each of multiple series connection circuits each formed of the semiconductor light source and the current source. A converter controller employing a ripple control method turns on a switching transistor of the switching converter in response to a voltage across any one of the multiple current sources decreasing to a bottom limit voltage.

A control circuit for a voltage source generates a reference signal for a voltage source, wherein the reference signal indicates a requested output voltage to be generated by the voltage source. A digital feed-forward control circuit computes a digital feed-forward regulation value indicative of a requested output voltage by determining a maximum voltage drop at strings of solid-state light sources. A digital feed-back control circuit determines a minimum voltage drop for current regulators/limiters for the strings and determines a digital feed-back correction value as a function of the minimum voltage drop. The control circuit then sets the reference signal after a start-up as a function of the digital feed-forward regulation value and corrects the reference signal as a function of the digital feed-back correction value.

A lighting arrangement such as a LED lamp comprises a light source and associated current driver, or a set of at least two parallel light sources and associated current drivers, supplied by a DC voltage from a voltage-regulated power converter. A feedback circuit provides a temperature-dependent control input to a control loop of the power converter, such that the DC voltage is adjusted in dependence on a sensed temperature. In this way, the voltage headroom required can be reduced, and efficiency gains are made.