JPH10322006A - Pad for polar chip part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make feasible of precisely judging the polarity as well as avoiding the erroneous wiring in the case of wiring a conductor pattern, by a method wherein a copper foil only of a pad to be the anode of a polar chip is expanded in the direction opposing to the cathode to indicate a mark by etching away the copper foil of the expanded anode side. SOLUTION: A copper foil pad 1 on an anode side for a polar chip (tantalum capacitor, etc.) different from another copper foil pad 2 is expanded outward to indicate a + mark 3 by etching away the copper foil. This + mark 3 is positioned outside the range of the solder resist relief 4 not to be soldered, so that the mark 3 may not be concealed to be easily confirmed even if the anodic chip pet is mounted to be soldered. Besides, the cathode side pad can be also expanded so as to form a - mark by etching away. Through these procedures, the polarity indication in the silk printing can be omitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pad for a polar chip component used for mounting a surface mount component on a printed wiring board.

[0001]

2. Description of the Related Art A conventional pad for a polar chip component of this type is, for example, a pad for mounting a chip component on a printed wiring board, which is disclosed in Japanese Utility Model Laid-Open No. 02-084365.

A chip component mounting pad provided on a printed wiring board disclosed in this publication will be described with reference to FIGS. 4 and 5. FIG. FIG. 4 is a plan view showing the shapes of the copper foil and solder resist relief of the chip component mounting pad, and FIG.
FIG. 3 is a schematic view showing a state where a component is actually mounted on a chip component mounting pad and subjected to a soldering process.

In these figures, a chip component mounting pad is composed of a copper foil pad 10 on the anode side and a copper foil pad 1 on the cathode side.
1 and a solder resist relief 12 for exposing a copper foil portion for soldering.

Since the polarity symbol 13 is clearly shown at the center of the copper foil pad on the anode side and the copper foil pad on the cathode side without etching, the polarity can be accurately determined, and the conductor pattern 14 can be determined. In addition, it is possible to prevent erroneous wiring at the time of mounting design for performing the above wiring and to prevent erroneous mounting by inverting the polarity when mounting the polarizable chip component 15 on the substrate.

[0005]

In the above-mentioned conventional chip component mounting pad, there is a problem that the polarity display becomes invisible when the component is mounted on the pad and soldering is performed. This is because the symbol displayed without etching is located at the center of the pad, and is partially hidden by the mounted component body, and is further within the solder resist escape range, so that the soldering process is performed.

Therefore, after mounting the component, the positional relationship between the polarity shown on the component body and the pad on the substrate must be checked based on the assembly drawing or confirmed by silk printing. The collation based on the assembly drawing is a visual check with the drawing, and the reliability in terms of quality is low. Also, there are restrictions on where to display silk-screened symbols, and the positioning of the symbols is performed while considering the escape from the drilled portion, the escape of the solder plating portion, and the overlap with the component outline, etc. It takes time, and there is a problem that the polarity of the pad and the display do not match due to a positioning error.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned disadvantages and to provide a chip component pad which can determine that a mounted component is mounted with the correct polarity even after the component is mounted.

[0008]

In order to solve the above-mentioned problems, a pad for a polar chip component according to the present invention extends only the copper foil of a pad on the anode side of the polar chip component in a direction facing the cathode side. Then, the + sign is clearly shown on the expanded copper foil portion on the anode side by etching.

With the above configuration, the polarity can be accurately determined based on the difference between the shape of the pad of the bipolar electrode and the presence or absence of the symbol, and erroneous wiring at the time of wiring the conductor pattern can be prevented as in the conventional case. Further, the symbol size after etching is the same as the size generally used in silk printing, so that it is easy to see, and silk printing can be omitted. Further, even when silk printing is required, the size and position of the etched + symbol sufficiently satisfy the restrictions in silk printing, and may be created in an overwritten state.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described in detail with reference to FIGS. FIG. 1 is a plan view showing the shapes of copper foil and solder resist relief for pads for a polar chip component (eg, a tantalum capacitor),
FIG. 2 is a schematic view showing the actual mounting of components on a pad for a polar chip component and soldering, and FIG. 3 is a view showing a copper foil pad, a conductor pattern and a perforated portion according to the present invention as viewed from the component mounting surface. FIG.

In these figures, the copper foil pad 1 on the anode side is expanded outwardly unlike the copper foil pad 2 on the cathode side, and a + sign 3 is clearly shown on the expanded copper foil portion by etching. I have. Since the position of the + symbol 3 is located outside the range of the solder resist relief 4, that is, a place where the soldering process is not performed, even if the anode chip component 5 is mounted and the soldering process 6 is performed, the display is not hidden and easily displayed. You can check. Even when silk printing is required, printing can be performed at the same position without considering restrictions such as escape from the perforated portion 7 or the solder plating portion 8 and overlap with other component outer shapes 9.

In the present invention, it is also possible to extend the cathode side pad and to form the minus sign by etching. Further, it is also possible to omit the electrode display by previously determining the expanded electrode as a + or-electrode.

[0013]

As described above, in the pad for a polar chip component of the present invention, only the copper foil of the pad corresponding to the anode side of the component is expanded, and a + sign is clearly indicated on the expanded copper foil portion without etching. Thus, the polarity can be accurately determined even after the components are mounted, and the polarity display in silk printing can be omitted. In the case of displaying the polarity by silk printing, the + sign etched out is used as a guide, and the time required to create a drawing can be reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of a pad for a polar chip component according to the present invention.

FIG. 2 is a schematic view showing a state in which a component is mounted on a pad for a polar chip component according to the present invention and subjected to a soldering process.

FIG. 3 is a diagram showing a copper foil pad, a conductor pattern, and a drilled portion of a pad for a polar chip component according to the present invention as viewed from a component mounting surface.

FIG. 4 is a plan view of a conventional chip component mounting pad.

FIG. 5 is a schematic view showing a state where components are mounted on a conventional chip component mounting pad and subjected to a soldering process.

[Explanation of symbols]

 Reference Signs List 1 Copper foil pad on anode side 2 Copper foil pad on cathode side 3 + sign 4 Solder resist escape 5 Polarized chip component 6 Soldering process 7 Drilled portion 8 Solder plating portion 9 Other component outline

Claims (3)

[Claims] In a pad provided with a copper foil and a solder resist for mounting a polar chip component on a printed wiring board, only the copper foil of one of the cathode and anode pads of the polar chip component is used. A pad for polarized chip parts characterized by being expanded. 2. The polar chip component pad according to claim 1, wherein the polarity of the electrode is displayed on an extended portion of the one electrode. 3. The pad for a polar chip component according to claim 1, wherein the polarity indication is formed by etching.