摘要:
An improved electromagnetic radiation (EMR) shield that has minimal airflow resistance is presented. The EMR shield includes: a base plate; and plurality of columns that project away from the base plate, wherein each of the columns has a first end that is attached to the base plate, a second end that is distal to the base plate, and a side surface that has at least one side hole therein.
摘要:
A grounding spring for electromagnetic interference (EMI) suppression is interposed between a heat sink and a printed circuit board (PCB). The grounding spring comprises a conductive material having an opening formed at its base through which the heat sink makes thermal contact with an electronic module mounted on the PCB. The base makes electrical contact with a peripheral surface of the heat sink, and multiple-jointed spring fingers extend from the base to make electrical contact with conductive pads on the PCB. During compression, the movement of each spring finger's tip is substantially limited to the z-axis. Accordingly, the final installed location of the tip can be precisely controlled even when the grounding spring must accommodate a wide variety of installed heights of the heat sink relative to the PCB. Preferably, the spring fingers terminate with a concave tip that is less susceptible to sliding off the conductive pads.
摘要:
Ferrite cores are provided with rounded, convex head ends and complimentary rounded, concave tail ends. The configuration of the head and tail ends permits a reduction in gap width between adjacent cores when they are joined together into a core assembly that suppresses electromagnetic interference emitted from a cable.
摘要:
In a first aspect, a first apparatus for providing radiated emission suppression in cabling is provided. The first apparatus includes (1) at least one cable; (2) one or more ferrite elements each substantially surrounding a length of the at least one cable; and (3) a capacitive sleeve element substantially surrounding a length of the at least one cable and the one or more ferrite elements. The capacitive sleeve element includes a conducting material adapted to be connected to a ground. Numerous other aspects are provided.
摘要:
The transferrable EMI gasket assembly utilizes a carrier with a pair of arms, each attached to a back panel by a hinged connection and extending in the same direction to overlie one another. The conductive, deformable gasket material is attached to the carrier and positioned adjacent the back panel. The assembly is collapsed for installation with the back panel overlying one of the arms hinged thereto to present a reduced height. The assembly is placed in the operative position by moving one arm relative to the other to pivot the carrier back panel to a near right angle position with respect to the carrier arms. In the operative position, the gasket material is compressed and deformed against the confronting surfaces to effect the EMI seal while the biasing force of the compressed gasket material, in the preferred embodiment, secures the carrier arms together.
摘要:
A method and multiple line scrambled clock architecture with random state selection are provided for implementing lower electromagnetic emissions. A clock distribution circuit receives a clock input and generates a plurality of scrambled sequences, each respectively coupled by one of a plurality of N clock distribution lines to a destination circuit. An exclusive OR connected to the N clock distribution lines unscrambles the plurality of scrambled sequences at the destination circuit. The plurality of scrambled sequences includes multiple bit clock representations, for example, 3 bit clock representations. The presence of 1s and 0s on each of the multiple N clock distribution lines is a substantially uniform distribution. The scrambled sequences are generally pseudorandom sequences.
摘要:
A grounding spring for electromagnetic interference (EMI) suppression is interposed between a heat sink and a printed circuit board (PCB). The grounding spring comprises a conductive material having an opening formed at its base through which the heat sink makes thermal contact with an electronic module mounted on the PCB. The base makes electrical contact with a peripheral surface of the heat sink, and multiple-jointed spring fingers extend from the base to make electrical contact with conductive pads on the PCB. During compression, the movement of each spring finger's tip is substantially limited to the z-axis. Accordingly, the final installed location of the tip can be precisely controlled even when the grounding spring must accommodate a wide variety of installed heights of the heat sink relative to the PCB. Preferably, the spring fingers terminate with a concave tip that is less susceptible to sliding off the conductive pads.
摘要:
A method for generating spread spectrum clock signals having harmonic emission suppressions is disclosed. A set of delayed clock signals is initially generated by delaying a high-speed clock signal via a set of delay modules. Then, the leading edge of a first one of the delayed clock signals is selectively combined with a trailing edge of any one of the delayed clock signals to form a half-period spread spectrum clock signal having low harmonic emissions.
摘要:
A device, system, and method for suppressing electromagnetic interference (EMI). In one embodiment, an EMI suppression device includes a compound ferrite core having an inner ferrite core and an outer ferrite core. The inner core includes a through hole in which a conductor may be mounted, and the outer core includes a hole in which said inner core is mounted in a concentrically offset manner. The outer core is rotatably adjustable with respect to the inner core in a manner such that the ferrite circuit cross-section area may be varied. The magnetic reluctance of the compound core is controlled in accordance with EMI suppression requirements by adjusting the circuit cross-section area.
摘要:
A fan and a fan blade are provided for allowing airflow through the fan blade in a fan failure condition. The fan blade includes a peripheral member defining an opening. A flexible cover member is attached to the peripheral member for covering the fan blade opening during normal operation of the fan. The flexible cover member is hingeably attached to the peripheral member for movement away from the peripheral member enabling airflow through the fan blade opening in a fan failure condition.