Patent classifications
H01J17/34
OVERVOLTAGE PROTECTION CIRCUIT
The present invention relates to an overvoltage protection circuit (1) for protecting the electronics of a motor, in particular of an EC motor, against overvoltage pulses, with two protective devices (FS1, FS2) arranged in series connection between two connections (10, 20), wherein a resistor (R1) or (R2) is connected in parallel to each of the protective devices (FS1, FS2) and at least one capacitive element (C1) is provided in parallel connection to the first protective device (FS1), wherein the overvoltage protection circuit (1) has, between the connections (10, 20), at least a first (lower) and a second (higher) breakdown voltage point at a voltage U.sub.Z1 or U.sub.Z2 dependent on the voltage change over time k=(dU/dt) of a voltage U.sub.GA at the connections (10, 20).
Electrical lighting circuit for a portable light
A lighting circuit includes a controllable electronic device in series with a power terminal of a controller, wherein operation of a switch causes the controller to maintain the electronic device conductive, whereby the controller then remains powered; and wherein the controller responds to a subsequent operation of the switch to render the electronic device nonconductive, whereby the controller is then unpowered even when electrical power is received. The lighting circuit is suitable for use, e.g., in a portable or other battery powered light.
LED tube lamp
An LED tube lamp includes a glass tube, two end caps, a power supply, and an LED light strip. The glass tube includes a main body region, two rear end regions, and two transition regions connecting the main body region and the rear end regions. The end cap is disposed at one end of the glass tube and the power supply is provided inside the end cap. The LED light strip is disposed inside the glass tube and has LED light sources disposed thereon. The LED light strip includes a bendable circuit sheet mounted on inner surface of the glass tube. The bendable circuit sheet of the LED light strip is formed with a freely extending end portion at one end, and the freely extending end portion is electrically connected to the power supply. The glass tube and the end cap are secured by a hot melt adhesive.
Light-emitting apparatus and lighting appliance provided with the same
In various embodiments, a light-emitting apparatus is disclosed. In one example, the light-emitting apparatus comprises a substrate, an LED string mounted on the substrate, in which LED string a plurality of LEDs are connected in series, a power supply path connected in series to the LED string, and a plurality of protection elements, each protection element having a first node commonly connected to the power supply path and a second node connected between a pair of the LEDs in the series, wherein the protection elements include capacitors or zener diodes, and an AC impedance of each protection element is smaller than an impedance between the pair of LEDs and a case ground.