In accordance with certain embodiments, lighting systems feature lightsheets including multiple illumination units or modules electrically interconnected such that unremoved illumination units or modules remain energized upon removal of at least a portion of one or more illumination units or modules.

A decorative light string is provided that includes a plurality of light emitting diode (LED) illumination assemblies electrically connected in series and a stabilizing current or voltage circuit. Each of the plurality of LED illumination assemblies includes an LED. The stabilizing current or voltage circuit is electrically connected in series with the plurality of LED illumination assemblies. The stabilizing current or voltage circuit is configured to receive input power from an input power source and configured to supply a stabilized current or voltage to the plurality of LED illumination assemblies that provides a stable supply even with input power source fluctuations. Power fluctuations from an input power source can prevent the decorative light string from maintaining a desired brightness and desired LED life unless the voltage or current to the LED illumination assemblies is stabilized.

A decorative light string is provided that includes a plurality of light emitting diode (LED) illumination assemblies electrically connected in series and a stabilizing current or voltage circuit. Each of the plurality of LED illumination assemblies includes an LED. The stabilizing current or voltage circuit is electrically connected in series with the plurality of LED illumination assemblies. The stabilizing current or voltage circuit is configured to receive input power from an input power source and configured to supply a stabilized current or voltage to the plurality of LED illumination assemblies that provides a stable supply even with input power source fluctuations. Power fluctuations from an input power source can prevent the decorative light string from maintaining a desired brightness and desired LED life unless the voltage or current to the LED illumination assemblies is stabilized.

A decorative light string is provided that includes a plurality of light emitting diode (LED) illumination assemblies electrically connected in series and a stabilizing current or voltage circuit. Each of the plurality of LED illumination assemblies includes an LED. The stabilizing current or voltage circuit is electrically connected in series with the plurality of LED illumination assemblies. The stabilizing current or voltage circuit is configured to receive input power from an input power source and configured to supply a stabilized current or voltage to the plurality of LED illumination assemblies that provides a stable supply even with input power source fluctuations. Power fluctuations from an input power source can prevent the decorative light string from maintaining a desired brightness and desired LED life unless the voltage or current to the LED illumination assemblies is stabilized.

A decorative light string is provided that includes a plurality of light emitting diode (LED) illumination assemblies electrically connected in series and a stabilizing current or voltage circuit. Each of the plurality of LED illumination assemblies includes an LED. The stabilizing current or voltage circuit is electrically connected in series with the plurality of LED illumination assemblies. The stabilizing current or voltage circuit is configured to receive input power from an input power source and configured to supply a stabilized current or voltage to the plurality of LED illumination assemblies that provides a stable supply even with input power source fluctuations. Power fluctuations from an input power source can prevent the decorative light string from maintaining a desired brightness and desired LED life unless the voltage or current to the LED illumination assemblies is stabilized.

A two-terminal IC chip and method thereof. For example, a two-terminal IC chip includes a first chip terminal and a second chip terminal. A first terminal voltage is a voltage of the first chip terminal, a second terminal voltage is a voltage of the second chip terminal, and a chip voltage is equal to a difference between the first terminal voltage and the second terminal voltage. The chip is configured to allow a chip current to flow into the chip at the first chip terminal and out of the chip at the second chip terminal, or to flow into the chip at the second chip terminal and out of the chip at the first chip terminal. The chip current is larger than or equal to zero in magnitude. The chip is further configured to change a relationship between the chip voltage and the chip current with respect to time. The chip is an integrated circuit, and the chip does not include any additional chip terminal other than the first chip terminal and the second chip terminal.

Provided is a standby current supplier including a bleeding circuit electrically connected to a dimmer and through which a first current flowing to the dimmer flows when the dimmer is in an off state, and a first controller configured to detect a first voltage corresponding to an input voltage generated by the dimmer and control the bleeding circuit based on the first voltage when the first voltage is lower than a predetermined first level.

A light emitting apparatus including: a light emitting array having at least one light emitting string of serial connected light emitting elements, wherein a bypass switch is connected in parallel to each light emitting element of said light emitting string; and a driving control unit controlling a shift timing of the bypass switches to reduce a variation of a voltage drop across the light emitting string.

A supply circuit adapted to provide a continuous power supply for a string of serially connected light emitting elements driven with a current source, said supply circuit including: a voltage supply capacitor connected to said string and being adapted to provide a supply voltage for a driving control unit configured to control the light emitting elements of said string; and a capacitor bypass switch connected in parallel with said voltage supply capacitor and being controlled by a local control circuit of said driving control unit, wherein said capacitor bypass switch is switched off by said local control circuit to charge said voltage supply capacitor with a charging current to maintain a continuous power supply without disturbing the current to said string of light emitting elements.

A light emitting device includes a series connection unit constituted of N light emitting elements, a light emitting element driving circuit having an output terminal connected to an anode of the series connection unit, N short-circuit switches respectively connected in parallel to the light emitting elements, and a switch control unit arranged to control on and off of the short-circuit switches. A ground fault detection circuit, which detects a ground fault of the light emitting device, includes a reference voltage source arranged to generate a reference voltage, and a comparator arranged to compare the anode voltage of the series connection unit with the reference voltage. The reference voltage has a value smaller than the product of an on-resistance of one of the short-circuit switches and output current of the light emitting element driving circuit.