Abstract:
Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Particular embodiments include clusters of small vias that effectively function as one large via, thereby increasing stop band bandwidth and maximizing parallel plate capacitance. Cluster vias can be configured to additionally provide a shielded and impedance matched route within the interior area of the cluster through which signal vias can connect transmission lines disposed in planes lying above and below the PPW. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.
Abstract:
A multilayer PCB including at least one carrier, wherein the at least one carrier comprises a pseudo three-layer core (110). Each three-layer core (110) includes a first metal layer (120), a first dielectric layer (124), an internal bridge layer (126), a second dielectric layer (125), and a second metal layer (122). The bridge layer includes a plurality of bridge pads (134). Each carrier includes a plurality of interlayer interconnection units (150a, 150n) for interconnecting the first and second metal layers. Each interlayer interconnection unit comprises a pair of opposed blind vias (140, 142) and a bridge pad (134) disposed between, and in electrical contact with, the pair of blind vias.
Abstract:
A high-speed router backplane, and method for its fabrication, are disclosed. The backplane uses differential signaling trace pairs on multiple high-speed signaling layers, the high-speed signaling layers separated by ground planes. Plated signaling thru-holes connect the trace pairs to the board surface for connection to external components. The signaling thru-holes pass through clearances in each ground plane. At selected ground planes, a conductive pad is patterned within each high-speed signaling thru-hole clearance, the pad slightly larger than the thru-hole diameter. The pads affect the impedance characteristics of the thru-holes, thus providing a better impedance match to the differential trace pairs, reducing signal reflections, and improving the ability to signal across the backplane at high speeds.
Abstract:
A circuit board free of wall separation and land separation even if a part is mounted by soldering using leadless solder. A circuit board (10) comprises N (N >= 3) layers electrically insulated from one another and has a through hole (14) into which an electrode (19) of an electronic part (18) is inserted. On the first and N-th layers, surface layer lands (15) are formed. On the inner wall of the through hole (14), a conductive layer (17) electrically connected to the surface layer lands (15)is formed. The electronic part (18) is so mounted as to be connected to the through hole (14) by filling the through hole (14) with leadless solder (20). At least one inner layer land (16) extending from the conductive layer (17) is formed in the same layer as the circuit of the M-th (M is an integer satisfying the relation 2
Abstract:
A multilayered wiring board using conductive pillars for the interconnection of wiring layers. Since through holes are bored in the via lands of the wiring layers of the multilayered wiring board, the stress applied between the conductive pillars and wiring layers can be released at the time of connecting the conductive pillars to the via lands. Since the external side face of each conductive pillar smoothly continues to the surface of the via land at the contact section between the conductive pillar and the via land, the notch effect is relieved. Therefore, the reliability of the interconnection is secured even when a stress is applied to the connections during the manufacturing of the multilayered wiring board, and the mounting of electronic parts, etc.
Abstract:
Disclosed is a multilayer printed circuit board (PCB) (300) having backdrill reliability anchors (314, 326, 328, 340) comprising nonfunctional pads to provide mechanical reinforcement for signal pads (310, 322, 326) on backdrilled plated through hole (PTH) vias (304, 316, 330), as well as associated method and machine readable storage medium.
Abstract:
[PROBLEMS] To provide a multilayer printed wiring board which does not deteriorate connection reliability by forming a filled via directly above a small-diameter filled via. [MEANS FOR SOLVING PROBLEMS] A stress applied on the filled via (60) formed on covering plating layers (36a, 36d) is larger than that applied on a filled via (160) formed on a second interlayer resin insulating layer (150) during a heat cycle. Thus, a bottom diameter (d1) of the filled via (60) is made larger than a bottom diameter (d2) of the filled via (160) formed directly above.