An LED tube lamp comprises a tube, an LED light strip inside the tube, a plurality of LED light sources on the LED light strip, a power supply, and a first and a second end caps. The power supply comprises a circuit board, a plurality of electronic components and a heat-dissipating element. The plurality of electronic components and the heat-dissipating element are on the circuit board. The first end cap and the second end cap are respectively attached at two ends of the tube. The first end cap comprises a lateral wall and an end wall having an opening. The lateral wall is substantially coaxial with the tube and connected to the tube. The end wall is substantially perpendicular to an axial direction of the lateral wall and connected to an end of the lateral wall away from the tube. At least some of the plurality of electronic components and the heat-dissipating element are disposed inside the first end cap. The heat-dissipating element is closer to the opening on the end wall of the first end cap than the electronic components in the end cap are.

A power supply apparatus for driving a light emitting apparatus is provided. The power supply apparatus includes a lossless snubber circuit and a power converting circuit. The lossless snubber circuit has a first diode, a first inductor and a second diode coupled in series between an input end and a first reference end, and has a first capacitor coupled between the first diode and a second reference end. The power converting circuit has a switch, a transformer and a second indictor. The switch is coupled between the first and second reference ends, and is turned on or off according to a control signal. The second inductor is coupled to a first side of the transformer in parallel.

A direct filtering type switching power supply is provided, for an occasion including pulsating direct current, including a filter circuit, a main power stage and an indicating circuit. A direct current input is connected to the filter circuit through the indicating circuit. The filter circuit and the main power stage are connected in parallel. The indicating circuit is formed by connecting a light emitting unit with an inductor in parallel, and make sure that the direction of the direct current input passing through the inductor is opposite to the conducting direction of the light emitting unit. The filter circuit at least includes an electrolytic capacitor. When the electrolytic capacitor is normal, an excitation current of a switching transistor in the main power stage basically does not appear in the inductor, and an LED in the light emitting unit does not emit light. When the Equivalent Series Resistance of the electrolytic capacitor rises greatly, the excitation current of the switching transistor appears in the inductor. Furthermore, when the switching transistor is switched off, the excitation current flowing through the inductor, which cannot be changed abruptly, freewheels through the LED, and drives the LED to emit light, so as to notify a user or a circuit that the electrolytic capacitor may have the risk of complete failure. The LED may also be a light emitter of a photocoupler. The switching power supply is low in cost, has unchanged efficiency and is easy to implement.

A circuit includes a power supply circuit and a ripple reduction circuit. The power supply circuit supplies a Direct Current (DC) lighting current to a light emitting circuit. The lighting current has a ripple current at a ripple frequency. The ripple reduction circuit receives the lighting current, and performs, based on the received lighting current, Pulse Width Modulation (PWM) of the lighting current at a PWM frequency. The PWM frequency is higher than the ripple frequency. By performing the PWM, the ripple reduction current reduces variations in a magnitude of the lighting current at the ripple frequency. The PWM frequency may be higher than a frequency at which variations in the magnitude of the light produced by the lighting circuit have a harmful effect on the human eye.

A high-efficiency LED driving circuit includes a rectifying module, a power converting module and a power supply module. The power converting module is connected to the rectifying module and a load, and includes a controller. The load includes a plurality of LEDs. The power input pin of the controller is connected to a connecting point and the connecting point is disposed between two of the LEDs. The quantity of the LEDs can be 2 or more than 2. The circuit design of the driving circuit can effectively reduce the power consumption and heat generation thereof, such that the reliability of the driving circuit can be effectively enhanced.

A power supply apparatus for driving a light emitting apparatus is provided. The power supply apparatus includes a lossless snubber circuit and a power converting circuit. The lossless snubber circuit has a first diode, a first inductor and a second diode coupled in series between an input end and a first reference end, and has a first capacitor coupled between the first diode and a second reference end. The power converting circuit has a switch, a transformer and a second indictor. The switch is coupled between the first and second reference ends, and is turned on or off according to a control signal. The second inductor is coupled to a first side of the transformer in parallel.

Switched-mode power supply (SMPS) integrated circuit including direct current step-down converter, switch, and element for potential energy storage in electric field and having T-On voltage. SMPS configured to: receive DC input current and output through load; operate in boundary conduction mode applying pulse-width-modulated voltage to switch for controlling T-On/T-Off duty cycle; generate regulated T-On current setting maximum T-On; monitor input voltage by reduction to voltage signal range; convert signal voltage to signal current value within current signal range; output T-On modulation current including signal current; combine T-On modulation current with regulated T-On current during T-On period to store potential energy in element while monitoring T-On voltage of element; and initiate T-Off period when potential energy stored in element reaches maximum T-On voltage. Further SMPS's. Method of operating SMPS's.

A dynamic lighting method and apparatus (100), in which at least one electrical parameter changing time period is configured during a lighting period; the method comprises: step 1, a power (PW) output starting electrical parameter and a power (PW) output ending electrical parameter are present within each electrical parameter changing time period, wherein a power (PW) output electrical parameters changes according to a same trend from the starting electrical parameter to the ending electrical parameter, and a starting point electrical parameter and an ending point electrical parameter within an electrical parameter changing time period are respectively equal to the electrical parameters within a non-electrical parameter changing time period before and after the electrical parameter changing time period; step 2, according to the step 1, enabling a dynamic lighting component to change lighting parameters during the electrical parameter changing time period, such that the change of the lighting parameters causes the eye structure of a user to be dynamically changed. The dynamic lighting method effectively maintains the eyesight of a user by means of actively training the physiological structure of the eyes of a user, without affecting eye-use habits, sitting posture and working pace of the user.

An LED tube lamp includes a tube having two ends, two end caps respectively at the ends of the tube, a power supply in one or both of the end caps, an LED light strip in the tube; and a plurality of LED light sources on the LED light strip. Each of the end caps comprises a lateral wall substantially coaxial with the tube, an end wall substantially perpendicular to an axial direction of the lateral wall, and at least one opening penetrating through the end wall. An axial direction of the at least one opening is substantially parallel with an axial direction of the lateral wall. The LED light sources electrically connected to the power supply via the LED light strip.

An LED tube lamp comprises a tube, an LED light strip inside the tube, a plurality of LED light sources on the LED light strip, a power supply, and a first and a second end caps. The power supply comprises a circuit board, a plurality of electronic components and a heat-dissipating element. The plurality of electronic components and the heat-dissipating element are on the circuit board. The first end cap and the second end cap are respectively attached at two ends of the tube. The first end cap comprises a lateral wall and an end wall having an opening. The lateral wall is substantially coaxial with the tube and connected to the tube. The end wall is substantially perpendicular to an axial direction of the lateral wall and connected to an end of the lateral wall away from the tube. At least some of the plurality of electronic components and the heat-dissipating element are disposed inside the first end cap. The heat-dissipating element is closer to the opening on the end wall of the first end cap than the electronic components in the end cap are.