摘要:
A system drives one or a plurality of LEDs, regulating their brightness by controlling the LEDs' average current or voltage. The system includes a switching power converter and an integrated digital regulator with at least one of electrical, thermal, and optical feedbacks. The regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of the power converter. For a discontinuous mode of operation of the power converter, a pulse averaging sliding mode control is used. Average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch. An input battery is protected from discharging at abnormally low impedance of the output.
摘要:
An exemplary apparatus embodiment provides for controlling current supplied to solid state lighting, such as light emitting diodes. An exemplary apparatus comprises a memory adapted to store a plurality of current parameters; and a control circuit adapted to modulate an energizing cycle time period for providing a substantially constant DC average current to the solid state lighting in response to a selected current parameter of the plurality of current parameters. In an exemplary embodiment, the control circuit modulates a current provided to the solid state lighting in response to a predetermined minimum current level (IMIN) parameter and a predetermined peak current level (IP) parameter, such that the DC average current level (IO) is substantially proportional to one-half of a sum of a predetermined peak current level (“IP”) and a predetermined minimum current level I M ( I O ∝ I P + I MIN 2 ) .
摘要翻译:示例性装置实施例提供用于控制提供给固态照明的电流,例如发光二极管。 示例性装置包括适于存储多个当前参数的存储器; 以及控制电路,其适于响应于所述多个当前参数的选定的当前参数,调制通电周期时间段,以提供基本上恒定的DC平均电流至所述固态照明。 在示例性实施例中,控制电路响应于预定的最小电流电平(IMIN)参数和预定的峰值电流电平(IP)参数来调制提供给固态照明的电流,使得DC平均电流电平(IO) 基本上与预定的峰值电流电平(“IP”)和预定的最小电流电平I MIN(IOαIP + I MIN 2)的和的一半成比例。
摘要:
An exemplary apparatus embodiment provides for controlling current supplied to solid state lighting, such as light emitting diodes. An exemplary apparatus comprises a memory adapted to store a plurality of current parameters; and a control circuit adapted to modulate an energizing cycle time period for providing a substantially constant DC average current to the solid state lighting in response to a selected current parameter of the plurality of current parameters. In an exemplary embodiment, the control circuit modulates a current provided to the solid state lighting in response to a predetermined minimum current level (IMIN) parameter and a predetermined peak current level (IP) parameter, such that the DC average current level (IO) is substantially proportional to one-half of a sum of a predetermined peak current level (“IP”) and a predetermined minimum current level I M ( I O ∝ I P + I MIN 2 ) .
摘要翻译:示例性装置实施例提供用于控制提供给固态照明的电流,例如发光二极管。 示例性装置包括适于存储多个当前参数的存储器; 以及控制电路,其适于响应于所述多个当前参数的选定的当前参数,调制通电周期时间段,以提供基本上恒定的DC平均电流至所述固态照明。 在示例性实施例中,控制电路响应于预定的最小电流电平(IMIN)参数和预定的峰值电流电平(IP)参数来调制提供给固态照明的电流,使得DC平均电流电平(IO) 基本上与预定的峰值电流电平(“IP”)和预定的最小电流电平IM(IOαIP + I MIN 2)的和的一半成比例。
摘要:
Exemplary apparatus, method and system embodiments provide for separately and independently sourcing current to a series of light emitting diodes of a plurality of series of light emitting diodes. An exemplary apparatus comprises a power converter which generates a current, a first multiplexer, and a controller. The controller provides for sequential and separate switching of the current through the first multiplexer to each of the series of light emitting diodes for a corresponding period of time. An average current provided by the power converter is determined as substantially equal to a sum of the corresponding currents through the plurality of series of light emitting diodes. A total period for switching current to all of the series of light emitting diodes is also determined. A corresponding time period for switching current to a selected corresponding series of light emitting diodes is substantially equal to a proportion of the total period determined as a ratio of the corresponding current for the selected corresponding series of light emitting diodes to the average current provided by the power converter.
摘要:
A system drives one or plurality of LEDs regulating their brightness by controlling LEDs average current or voltage. The system includes a switching power converter and an integrated digital regulator with at least one of electrical, thermal and optical feedbacks. The regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of the power converter. For discontinuous mode of operation of the power converter a pulse averaging sliding mode control is being used. Average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch. Input battery is protected from discharging at abnormally low impedance of the output.
摘要:
A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes, where at least one of the operation modes is a peak current switching mode. Under the peak current switching mode, a switch controller controls the switch in the power converter to be kept on until the current through the switch reaches a peak current value corresponding to a given phase of the input voltage signal to the power converter. The peak current values have a reference shape, which may be a trapezoidal. The power converter may have any topology, such as a flyback-type power converter or a boost-type power converter.
摘要:
A system drives one or plurality of LEDs regulating their brightness by controlling LEDs average current or voltage. The system includes a switching power converter and an integrated digital regulator with at least one of electrical, thermal and optical feedbacks. The regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of the power converter. For discontinuous mode of operation of the power converter a pulse averaging sliding mode control is being used. Average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch. Input battery is protected from discharging at abnormally low impedance of the output.
摘要:
Representative method and computer-readable medium embodiments provide for sourcing current to a series of light emitting diodes in a plurality of series of light emitting diodes. A representative method comprises generating a current, sequentially and separately switching the current to each of the series of light emitting diodes in the plurality of series of light emitting diodes for a corresponding period of time, and predicting an output voltage across a selected series of light emitting diodes using a plurality of parameters stored in a memory.
摘要:
Exemplary apparatus, method and system embodiments provide for separately and independently sourcing current to a series of light emitting diodes of a plurality of series of light-emitting diodes. An exemplary apparatus comprises a power converter which generates a current, a first multiplexer, and a controller. The controller provides for sequential and separate switching of the current through the first multiplexer to each of the series of light-emitting diodes for a corresponding period of time. An average current provided by the power converter is determined as substantially equal to a sum of the corresponding currents through the plurality of series of light-emitting diodes. A total period for switching current to all of the series of light-emitting diodes is also determined. A corresponding time period for switching current to a selected corresponding series of light-emitting diodes is substantially equal to a proportion of the total period determined as a ratio of the corresponding current for the selected corresponding series of light-emitting diodes to the average current provided by the power converter.
摘要:
An exemplary embodiment provides a current regulator for controlling variable brightness levels for solid state lighting. The current regulator is couplable to a phase-modulating switch, such as a dimmer switch, which is coupled to an AC line voltage. An exemplary current regulator includes a rectifier; a switching power supply providing a first current; an impedance matching circuit; and a controller. The impedance matching circuit is adapted to provide a second current through the phase-modulating switch when a magnitude of the first current is below a first predetermined threshold, such as a holding current of a triac of the phase-modulating switch. The controller is adapted to determine a root-mean-square (RMS) voltage level provided by the phase-modulating switch from the AC line voltage and to determine a duty cycle for pulse-width current modulation by the switching power supply in response to the comparison of the RMS voltage level to a nominal voltage level.