Printed circuit board having axially parallel via holes
Disclosed is a PCB having axially parallel via holes, in which an outer ground via hole, acting as a ground, is formed around a via hole for intercircuit connection in the PCB, thereby minimizing the effect of noise caused by the via hole.
1. A printed circuit board having axially parallel via holes, comprising:
a plurality of circuit layers, on which circuit patterns are formed;
a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers;
a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof;
an outer ground via hole having a continuous curvilinear section surrounding at least two via holes of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof;
an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole; and
wherein the via hole, which is surrounded by the outer ground via hole, is selected from the group consisting of:
an inner via hole electrically connecting at least two internal circuit layers;
a staggered via hole having a step-shaped path and electrically connecting at least two circuit layers;
a stacked via hole having an straight-shaped path and electrically connecting at least two circuit layers;
a through via hole electrically connecting the external circuit layers; and
a blind via hole electrically connecting at least two circuit layers, wherein the blind via hole does not pass completely through the printed circuit board.
2. The printed circuit board as set forth in claim 1 , wherein the outer ground via hole is grounded.
3. The printed circuit board as set forth in claim 1 , wherein the second conductive material of the outer ground via hole is a copper plating layer.
4. The printed circuit board as set forth in claim 1 , wherein the via hole, which is surrounded by the outer ground via hole, is coaxial to the outer ground via hole.
5. The printed circuit board as set forth in claim 1 , wherein the via hole, which is surrounded by the outer ground via hole, is axially parallel to the outer ground via hole.
6. A printed circuit board having axially parallel via holes, comprising:
a plurality of circuit layers, on which circuit patterns are formed;
a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers;
a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof;
an outer ground via hole having a continuous curvilinear section surrounding at least two via holes of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof;
an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole; and
wherein the via hole, which is surrounded by the outer ground via hole, is selected from the group consisting of:
an inner via hole electrically connecting at least two internal circuit layers;
a staggered via hole having a step-shaped path and electrically connecting at least two circuit layers;
a stacked via hole having an straight-shaped path and electrically connecting at least one internal and at least one external circuit layers;
a blind via hole electrically connecting at least two circuit layers, wherein the blind via hole does not pass completely through the printed circuit board.
7. A printed circuit board having axially parallel via holes, comprising:
a plurality of circuit layers, on which circuit patterns are formed;
a plurality of insulating layers interposed between the plurality of circuit layers, thereby forming internal and external circuit layers;
a plurality of via holes having a continuous curvilinear section, which extends perpendicular to a surface of any one of the plurality of circuit layers and which is plated with a first conductive material on walls thereof;
an outer ground via hole surrounding at least one via hole of the plurality of via holes, which extends transverse to and for a distance equal to the thickness of at least three insulating layers having internal circuit layers disposed therebetween, the outer ground via hole extending in an axial direction of the via hole surrounded thereby while being separated from a wall of the via hole by a predetermined distance and which is plated with a second conductive material on the wall thereof; and
an insulating material packed between the via hole, which is surrounded by the outer ground via hole, and the outer ground via hole.