Abstract: A laminated shielding inductor includes a laminated body, an internal coil, and a shielding cover; the laminated body includes a plurality of insulator layers; shielding conductor through grooves which are located at the periphery of the internal coil are formed in the plurality of insulator layers; shielding conductors are arranged in the shielding conductor through grooves, are electrically and mutually connected and jointly form a shielding conductor laminated layer; a shielding conductor upper layer and a shielding conductor lower layer are respectively arranged above and below the internal coil; and the shielding conductor laminated layer, the shielding conductor upper layer and the shielding conductor lower layer are closed to form the shielding cover. Thus, high shielding effect of the laminated chip inductor can be realized, external radiation of the laminated chip inductor is effectively reduced, and the reliability of a circuit system is improved.

Abstract: A method for manufacturing a back drilling hole in a printed circuit board (PCB) and PCB are provided. The method for manufacturing the back drilling hole comprises: forming a through hole in the PCB (1); forming a metal layer (12) with prescribed thickness on an inner wall of the through hole; filling resin in the through hole which has been formed with the metal layer (12); performing back drilling machining on the through hole which has been filled with the resin; removing metal scraps remained in the through hole. The manufacturing method protects the hole wall copper by filling the hole with the resin, so that acid corrosion process only removes the remained metal scraps after back drilling of the small hole, does not affect on the hole copper of the resin protecting portion.

Abstract: A method for detecting back-drilled holes in a PCB and a PCB panel are provided. The method comprises: forming, on a metal layer of a first inner layer of a multi-layer PCB, metal rings according to positions of the back-drilled holes during a process of forming the PCB, wherein each of the formed metal rings has an outer diameter greater than an aperture of each of the back-drilled holes; forming, at positions corresponding to the positions of the back-drilled holes, metal holes extending through an outer layer of the PCB and the formed metal rings; forming two first detection holes electrically connected with the formed metal rings; forming the back-drilling holes on the PCB, which extend through and expand the metal holes; and detecting an electrical conduction between the two first detection holes so as to determine whether a position offset exists between the back-drilled holes and the metal holes.

Abstract: A method for detecting back-drilled holes in a PCB and a PCB panel are provided. The method comprises: forming, on a metal layer of a first inner layer of a multi-layer PCB, metal rings according to positions of the back-drilled holes during a process of forming the PCB, wherein each of the formed metal rings has an outer diameter greater than an aperture of each of the back-drilled holes; forming, at positions corresponding to the positions of the back-drilled holes, metal holes extending through an outer layer of the PCB and the formed metal rings; forming two first detection holes electrically connected with the formed metal rings; forming the back-drilling holes on the PCB, which extend through and expand the metal holes; and detecting an electrical conduction between the two first detection holes so as to determine whether a position offset exists between the back-drilled holes and the metal holes.