JPH0611533Y2 - Printed board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a printed circuit board on which surface mount components are mounted, and more particularly to the shape of an inner layer copper foil of the printed circuit board.

[Prior Art] Conventionally, in a printed circuit board on which surface-mounted components are mounted, by providing a window 12 in the entire pad row as shown in FIG. It has a structure that allows light to pass through.

This makes it easy to identify the solder bridge when the surface mount component is soldered.

[Problems to be Solved by the Invention] In the above-described conventional printed circuit board, the inner copper foil is provided with the window 7 so that the inner copper foil has the inner copper foil portion 10 inside the pad row and the inner copper foil portion outside. While being divided into 11, the inner layer copper foil portions 10 and 11 are connected to each other only at four places of the copper foil portion 13 having a small width a as shown in FIG.

Therefore, there is a drawback that a potential difference is likely to occur between the inner layer copper foil portions 10 and 11 within the inner layer copper foil surface.

[Means for Solving Problems] The present invention which solves the above-mentioned conventional problems provides a printed circuit board on which surface mount components are mounted via component pads.
A window is provided at a position corresponding to the space between the component pads of the inner layer copper foil immediately below the component pads.

[Embodiment] Next, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of a printed circuit board embodying the present invention disassembled into layers, FIG. 2 is a top view showing the shape of an inner layer copper foil of the printed circuit board of the present invention, and FIG. FIG. 6 is a perspective view of the vicinity of a pad when a surface mount component is mounted on a printed circuit board. However, the surface indicated by the arrow X represents a cross section.

The printed circuit board of this embodiment is formed by laminating a first layer board 2, an inner layer copper foil 3 serving as a second layer, a substrate 4, an inner layer copper foil 5 serving as a fourth layer, and a fifth layer board 6. ing.

On the first layer plate 2 and the fifth layer plate 6, a pad row formed by arranging a plurality of pads (six in this embodiment) for mounting surface-mounted components at predetermined intervals is formed in a quadrangle as shown in the figure. It is arranged.

Further, a plurality of windows 7 having substantially the same shape as the pad 1 are provided side by side at the positions corresponding to the pads 1 of the inner copper foils 3, 5 mentioned above. The rows of the windows 7 are also arranged in a quadrangle like the pad row.

As shown in FIG. 3, which is an enlarged view of the vicinity of the pad 1 when the surface mount portion is mounted, the windows 7 of the inner layer copper foils 3 and 5 are located between the pads 1, so that this window Light is transmitted through 7. Immediately below the pad 1, there is a portion between the windows 7 of the inner layer copper foils 3 and 5. Inner layer copper foil 3,
The inner portion of the pad row of 5 and the outer portion of the inner copper foils 3, 5 are connected by the portions between the windows 7, but the range of this connecting portion is sufficiently wide so that a potential difference hardly occurs.

In addition, 8 is a lead of a surface mount component.

[Effects of the Invention] As described above, the present invention provides a printed circuit board on which surface mount components are mounted via component pads, and a window is provided at a position corresponding to the component pads of the inner layer copper foil immediately below the component pads. By providing the above, it becomes possible to easily detect the solder bridge between the pads by transmitting light, and it is possible to reduce the potential difference between the inner copper foil inside and outside the pad row.

[Brief description of drawings]

FIG. 1 is a perspective view of the printed circuit board of the present invention exploded for each layer, FIG. 2 is a top view of an inner copper foil of the printed circuit board of the present invention, and FIG. FIG. 4 is a partial perspective view of the mounted state, and FIG. 4 is a top view of the inner layer copper foil of the conventional printed circuit board. 1: Pad, 2: First layer board 3: Inner layer copper foil, 4: Base material 5: Inner layer copper foil, 6: Fifth layer board 7: Window 8: Lead of surface mount component

Claims (1)

[Scope of utility model registration request] 1. A printed circuit board on which surface mount components are mounted via component pads, wherein windows are provided at positions corresponding to each other between the component pads of an inner layer copper foil immediately below the component pads. substrate.