45results about How to "Solve EMI problems" patented technology

The invention discloses a switching circuit which is capable of reducing space requirement of products, and enhancing flexibility of product design and prolonging service lives of the products. Besides, the switching circuit is high in anti-disturbance performance and is reliable in performance. The switching circuit comprises a trigger button, a semiconductor control component and a switch tube. When the switching circuit is in an off-state and the trigger button is triggered, the switch tube is conducted, and the switching circuit is switched from the off-state to an on-state. Besides, the semiconductor control component is conducted, and the conducted semiconductor control component keeps the on-state of the switching circuit. When the switching circuit is in the on-state and the trigger button is triggered, current flowing through the semiconductor control component is bypassed, and the semiconductor control component is turned off. After the trigger button bounces back, the switch tube is cut off, and when the switch tube is cut off, the switching circuit is switched from the on-state to the off-state.

The invention relates to a parallel connection jitter frequency switch power supply, which comprises a switch driving module and at least two power supply modules in electric parallel connection, wherein the switch driving module sends out at least two switch driving signals for correspondingly driving at least two power supply modules, and the switch frequencies of at least two switch driving signals are fixed and are different. The invention also correspondingly provides a parallel connection jitter frequency method for the switch power supply. Through setting fixed and different switch frequencies for each power supply module or further setting fixed and different switch frequency for power supply sub modules in the power supply module, the harmonic interference is effectively scattered, the harmonic interference energy is reduced, and the electromagnetic interference (EMI) problem of the whole switch power supply system is solved.

In the combination structure of sheet metal parts in which a first sheet metal part 31 and a second sheet metal part 41 are combined by a screw member 50 with the respective connecting surfaces being opposed to each other, a first prepared hole 32 smaller in diameter than the screw member 50 is formed in the first sheet metal part 31, and a number of first small holes 33 smaller in diameter than the first prepared hole 32 are formed around the first prepared hole 32. When the first part 31 is connected to the second part 41 by the screw member 50, a strain force is generated around the first prepared hole 32 by screwing the screw member 50 to the first hole 32, and projections formed in the first small holes 33 are brought into contact with the second part 41 by the strain force.

The present invention discloses a quasi-resonance flyback switching power supply system. The system comprises a transformer, a power switch, and a quasi-resonance controller consisting of a jitter frequency module and a valley bottom control module. The jitter frequency module regulates the switching frequency of the power switch through regulation of a peak current flowing through a primary winding of the transformer, or regulates the switching frequency of the power switch through addition of an advance value or a delay value at the resonance valley bottom of a drain electrode voltage of thepower switch; and the valley bottom control module performs operation and processing of a size relation of the switching frequency of the power switch and a first reference frequency and a second reference frequency to obtain increased valley bottom signals or decreased valley bottom signals so as to control the power switch to convert from an off state to an on state at the predetermined resonance valley bottom of the drain electrode voltage thereof according to the increased valley bottom signals or the decreased valley bottom signals.

The invention provides an encoding and decoding method, device and system based on an LVDS (Low Voltage Differential Signaling) interface, which relates to the field of liquid crystal displays and is invented to avoid electromagnetic interference problem. The encoding method comprises the following steps of obtaining gray scale of RGB (Red Green Blue) image data in data to be encoded; determining the gray scale as a preset specific gray scale; setting an indicating identifier so that an decoder can obtain that the data to be decoded is the data corresponding to the preset specific gray scale according to the indicating identifier; and carrying out transposition on specific digits of binary number corresponding to the RGB image data so that the transmission frequency of the RGB image data is reduced after the transposition. The encoding and decoding method, device and system based on the LVDS interface can be used for data transmission of the LVDS interface.

The invention is a shielded protection device in wireless local network card, it includes protective pedestal and protective cover, the pedestal is set on the circuit board of the card and it includes the body and the frame. The frame is set at sides and it has protuberant thing. The cover includes the body and the ouches, the ouches are set at sides of the cover. The ouches have hole and clamp, the fasting hole is between the clamp and the cover. It is used to connect with the protuberant thing. The clamp wedges the protuberant thing. In this design, the pressure of the pedestal and the cover increases and the resistance is decreased, in order to avoid the leakage of electromagnetism wave.

The invention provides laser cinema equipment. A circuit system framework of electronic equipment comprises a shell; a ground plane plate is mounted on a base of the shell; the ground plane plate is provided with a bottom plate and side plates perpendicular to the bottom plate; a light source and an optical machine are mounted on the bottom plate; the circuit system framework further comprises atleast two circuit boards; the at least two circuit boards are mounted on the bottom plate and the side plates; the at least two circuit boards are grounded; and the circuit board mounted on the bottomplate is a power supply board. According to the laser cinema equipment provided by the embodiment of the invention, one complete and uniform large-area ground plane plate is formed by the bottom plate and the side plates, so that a complete ground circuit can be provided for backflow of an electric signal, and the serious EMI problem caused by the electronic equipment is prevented.