A light-emitting diode (LED) luminaire comprises an emergency-operated portion comprising a rechargeable battery with a terminal voltage, a self-diagnostic circuit, and a node modulator-demodulator (MODEM). The LED luminaire can auto-switch from a normal power to an emergency power according to availability of the normal power and whether a rechargeable battery test is initiated. The self-diagnostic circuit comprises a clock and is configured to initiate self-diagnostic tests and to auto-evaluate battery performance according to test schedules with the terminal voltage examined and test results stored. The LED luminaire further comprises a remote controller configured to initiate control signals with phase-shift keying (PSK) signals transmitted and to collect test data to and from the node MODEM. The node MODEM is configured to demodulate the PSK signals and to send commands to the self-diagnostic circuit to request responses accordingly.

A lighting and energy conservation system for low temperature applications includes LEDs as a light source. The LEDs are provided in a modular LED light fixture. The fixture includes a frame supporting a reflector having a plurality of elongated channels. Mounting strips are removably installed in each of the elongated channels, and LEDs are mounted on each of the mounting strips. A separate power control device is associated with each of the mounting strips, so that a total light output intensity and profile of the fixture can be individually customized by selectively adjusting the power control device for each of the mounting strips.

A fluorescent lamp replacement may include one or more LED drivers and lamps in various embodiments, as well as a shock hazard/pin safety circuit. The present invention provides a fluorescent lamp replacement that, for example, powers an LED and/or OLED and/or QD lamp from a fluorescent fixture, including operating 5 and being powered by electronic ballasts. In some embodiments, a fluorescent lamp replacement includes a number of pins configured to electrically connect to a fluorescent lamp fixture, at least one non-fluorescent light source, a transistor between at least one of the pins and the at least one non-fluorescent light source, and a shock hazard protection circuit configured to disable the transistor to limit current flowing through at least some of the pins.

A light-emitting diode (LED)-based solid-state lamp (LED lamp) comprising four input ports, two bridge rectifiers, two interface modules, an LED driving circuit, and LED arrays operates normally for an input voltage applied from any two of the input ports without operational uncertainty and a fire hazard. The LED driving circuit is configured to provide a regulated power and current to drive the LED arrays. With a cycle-by-cycle triac switching and current control, an over-rated surge current is limited, preventing any fire hazards possibly occurred in the ballast when operated with the LED lamp. With various electrical connection terminals, the lamp can fit and operate in various lamp fixtures comprising two-pin, four-pin, or Edison-base sockets.

The invention provides a retrofit LED lamp driver having a shunt switch to alternately shunt (for a first duration) and not shunt (for a second duration) received AC power. The first duration is concurring with a first polarity of each AC cycle of the AC power, for a first period comprising at least one AC cycle, and the first duration is concurring in a second, opposite polarity of the AC power, for a second period comprising another at least one AC cycle not overlapping with the first duration. Alternating the first and second periods are provided. Any DC offset in the current drawn caused by the shunting operation is thereby cancelled over time.

The invention provides a retrofit LED lamp driver having a shunt switch to alternately shunt (for a first duration) and not shunt (for a second duration) received AC power. The first duration is concurring with a first polarity of each AC cycle of the AC power, for a first period comprising at least one AC cycle, and the first duration is concurring in a second, opposite polarity of the AC power, for a second period comprising another at least one AC cycle not overlapping with the first duration. Alternating the first and second periods are provided. Any DC offset in the current drawn caused by the shunting operation is thereby cancelled over time.

An LED lamp arrangement is disclosed to replace a fluorescent lamp in a luminaire with a ballast. The LED lamp arrangement has a rectifier, LEDs, a LED driver, an impedance balance circuit, a line-voltage controller. The rectifier has two inputs connected to the ballast to provide a rectified power line and a ground power line. The LEDs and a LED driver are connected in series between the rectified power line and the ground power line, and the LED driver regulates a LED driving current through the LEDs. The impedance balance circuit is coupled between the inputs. The line-voltage controller controls the impedance balance circuit in response to a line voltage at the rectified power line, so as to tune an impedance between the inputs and make the line voltage approach to a predetermined target voltage.

A lamp including a light source having at least one string of light emitting diodes on a printed circuit board present within a tube body; and end caps having a G13 pin layout on each end of the tube body. The lamp may further include an electrical isolation switch mounted on at least one of the end caps, wherein the electrical isolation switch provides shock protection from the lamp when installed into a ballast free fixture. The lamp may further include driver electronics having a filament detector portion provided by a passive resistance capacitor (RC) circuit that simulates the filament load of a fluorescent lamp when installed into a ballast containing fixture.

A lamp including a light source having at least one string of light emitting diodes on a printed circuit board present within a tube body; and end caps having a G13 pin layout on each end of the tube body. The lamp may further include an electrical isolation switch mounted on at least one of the end caps, wherein the electrical isolation switch provides shock protection from the lamp when installed into a ballast free fixture. The lamp may further include driver electronics having a filament detector portion provided by a passive resistance capacitor (RC) circuit that simulates the filament load of a fluorescent lamp when installed into a ballast containing fixture.

This disclosure relates to a LED driving circuit compatible with an electronic ballast and an electronic supply, and a LED lamp, which include a first input terminal receiving an alternating current, a second input terminal, a buck circuit connected with the first input terminal and the second input terminal, a rectifier circuit connected with the buck circuit, a leakage current limit circuit connected with the rectifier circuit, a constant current output circuit connected with the leakage current limit circuit, a signal sample circuit connected with the second input terminal and the leakage current limit circuit, and a switch connected with the leakage current limit circuit. When a high frequency voltage outputted by the connected electronic ballast is automatically depressed for protecting subsequent circuits, when connecting the electronic supply, it is satisfied with a single terminal and double terminals connecting a power, and the double terminals pass a leakage current test.