Abstract: A circuit for suppressing electromagnetic interference signal on power lines. The circuit includes a first sensing circuit, a first amplifier, and a first controlled signal source. The first sensing circuit is arranged to sense a first electromagnetic interference signal. The first amplifier is arranged to be powered by a power source. The first amplifier provides a first amplification factor and being operably connected with the first sensing circuit to amplify a signal sensed by the first sensing circuit. The first controlled signal source provides a second amplification factor and is operably connected with the first amplifier to regulate or further amplify the amplified signal to provide a first suppression signal that reduces the first electromagnetic interference signal. Multiple such circuits can be cascaded to form a mufti-stage electromagnetic interference suppression circuit.

Abstract: A circuit for suppressing electromagnetic interference signal on power lines. The circuit includes a first sensing circuit, a first amplifier, and a first controlled signal source. The first sensing circuit is arranged to sense a first electromagnetic interference signal. The first amplifier is arranged to be powered by a power source. The first amplifier provides a first amplification factor and being operably connected with the first sensing circuit to amplify a signal sensed by the first sensing circuit. The first controlled signal source provides a second amplification factor and is operably connected with the first amplifier to regulate or further amplify the amplified signal to provide a first suppression signal that reduces the first electromagnetic interference signal. Multiple such circuits can be cascaded to form a mufti-stage electromagnetic interference suppression circuit.

Abstract: A device and method for reducing current ripple to a light emitting diode array having a single stage power factor correction driver with an output voltage ripple that is reduced by using a linear current regulator connected in series between the single stage power factor correction driver and the light emitting diode array, which actively adjusts an equivalent impedance of the linear current regulator in correspondence with the output voltage ripple of the single stage power factor correction driver.

Abstract: An LED lighting circuit where the configuration of the connection of two or more LEDs are changed from parallel to series through the use of solid state switches depending on whether the voltage level from an AC source measured by a voltage detector exceeds the sum of the forward voltages of the LEDs. Also, a method of activating LEDs in an LED array lighting apparatus involving applying a rectified alternating current to two or more LEDs, each LED having a forward bias voltage; comparing the rectified alternating current to the sum of the forward bias voltages of the two or more LEDs; and changing the circuit configuration of the two or more LEDs between a parallel connection and a series connection with respect to the rectified alternating current depending on whether the rectified alternating current exceeds the sum of the forward bias voltages of the two or more LEDs.

Abstract: An LED lighting circuit where the configuration of the connection of two or more LEDs are changed from parallel to series through the use of solid state switches depending on whether the voltage level from an AC source measured by a voltage detector exceeds the sum of the forward voltages of the LEDs. Also, a method of activating LEDs in an LED array lighting apparatus involving applying a rectified alternating current to two or more LEDs, each LED having a forward bias voltage; comparing the rectified alternating current to the sum of the forward bias voltages of the two or more LEDs; and changing the circuit configuration of the two or more LEDs between a parallel connection and a series connection with respect to the rectified alternating current depending on whether the rectified alternating current exceeds the sum of the forward bias voltages of the two or more LEDs.

Abstract: A device and method for reducing current ripple to a light emitting diode array having a single stage power factor correction driver with an output voltage ripple that is reduced by using a linear current regulator connected in series between the single stage power factor correction driver and the light emitting diode array, which actively adjusts an equivalent impedance of the linear current regulator in correspondence with the output voltage ripple of the single stage power factor correction driver.

Abstract: A circuit includes a driver configured to generate an output for driving one or more light emitting diodes. The circuit also includes a voltage booster configured to boost an input voltage provided to the driver when the voltage booster is coupled to a high-frequency pulsating alternating current (AC) voltage source that provides the input voltage. The voltage booster may include two first diodes coupled in series, two second diodes coupled in series, and first and second capacitors coupled in series. A first input voltage terminal may be coupled between the first diodes, and a second input voltage terminal may be coupled between the second diodes and between the capacitors. The voltage booster may be further configured to provide the input voltage to the driver without boosting when the voltage booster is coupled to a direct current (DC) or low-frequency AC voltage source that provides the input voltage.