An LED drive circuit includes a power supply terminal, an LED, a first switch, and a first resistor are connected in series. The power supply terminal, a third resistor, and a second switch are connected in series. A connection point between the third resistor and the second switch, and a control terminal of the first switch are connected. A second resistor is connected between a connection point between the first switch and the first resistor, and a control terminal of the second switch. A first PTC thermistor is connected to a connection point between the control terminal of the second switch and the second resistor.

An LED drive circuit includes a power supply terminal, an LED, a first switch, and a first resistor are connected in series. The power supply terminal, a third resistor, and a second switch are connected in series. A connection point between the third resistor and the second switch, and a control terminal of the first switch are connected. A second resistor is connected between a connection point between the first switch and the first resistor, and a control terminal of the second switch. A first PTC thermistor is connected to a connection point between the control terminal of the second switch and the second resistor.

An elongate tubular lighting assembly having a body with a length between spaced first and second ends. The tubular lighting assembly has a source of illumination and first and second connectors respectively at the first and second body ends. The first connector has cooperating first and second parts having first and second surfaces. The first and second connector parts are configured so that the first and second surfaces are placed in confronting relationship to prevent separation of the first and second connector parts with the body in an operative state as an incident of the first connector part moving relative to the second connector part from a position fully separated from the second connector part in a substantially straight path that is transverse to the length of the body into an engaged position.

The present invention provides a device for generating ultraviolet (UV) radiation whose wavelength is optimally tuned into the range of 240 to 290 nm, with peak wavelength in the range of 260 to 270 nm, which attains a Peak Germicidal Disinfection Effective Index of nearly 100%, superior to conventional UV lights and lamps. This device comprises a light-emitting diode (LED) matrix, a fan, an LED driver, a base and a motion sensor with programmable sensitivity and time delay. It may further comprise components for thermal protection and active air circulation. When operating, the device emits visible UVA radiation and blue light. With special considerations for user safety, the device effectively protects users from exposure to UV hazards and is safe to use. With the built-in thermal protection, this device may be used with either open or enclosed fixtures.

A lighting unit for illuminating a habitat is provided. The lighting unit includes a housing and a light emitter. The operating parameters of the lighting unit may be adjusted to mimic different natural conditions.

A lighting unit for illuminating a habitat is provided. The lighting unit includes a housing and a light emitter. The operating parameters of the lighting unit may be adjusted to mimic different natural conditions.

A lighting device to generate light in a horticultural environment includes one or more groups of emitters, each of the one or more groups of emitters exhibiting a respective characteristic spectral power distribution; one or more power conversion circuitry units, each of the one or more power conversion circuitry units configured to modulate power to its respective one of the one or more groups of emitters; at least one processor configured to generate and transmit control signals to the one or more power conversion circuitry units; at least one temperature sensor coupled to the at least one processor and positioned near at least one of the one or more groups of emitters; and a memory unit coupled to the at least one processor and configured to store data relating to the one or more groups of emitters and the control signals.

A lighting device to generate light in a horticultural environment includes one or more groups of emitters, each of the one or more groups of emitters exhibiting a respective characteristic spectral power distribution; one or more power conversion circuitry units, each of the one or more power conversion circuitry units configured to modulate power to its respective one of the one or more groups of emitters; at least one processor configured to generate and transmit control signals to the one or more power conversion circuitry units; at least one temperature sensor coupled to the at least one processor and positioned near at least one of the one or more groups of emitters; and a memory unit coupled to the at least one processor and configured to store data relating to the one or more groups of emitters and the control signals.

An underwater light including a programmable controller and a replaceable light-emitting diode (LED) printed circuit board assembly (PCBA) is provided. The light includes a controller PCBA in communication with the LED PCBA, and a connector for connecting the controller PCBA to the LED PCBA. An optically-transparent potting compound encapsulates the LED PCBA, and the LED PCBA can be safely replaced by removing a rear housing of the underwater light.

An underwater light including a programmable controller and a replaceable light-emitting diode (LED) printed circuit board assembly (PCBA) is provided. The light includes a controller PCBA in communication with the LED PCBA, and a connector for connecting the controller PCBA to the LED PCBA. An optically-transparent potting compound encapsulates the LED PCBA, and the LED PCBA can be safely replaced by removing a rear housing of the underwater light.