JPH0582936A - Electric circuit for leadless component-loading substrate - Google Patents

Abstract

PURPOSE:To reduce impedance among a plurality of leadless components when the leadless parts are connected in parallel on the conductor pattern of a printed wiring board. CONSTITUTION:Two leadless-capacitors 1 are connected in parallel on the conductor patterns 3 of a printed wiring board 2 by soldered joints 4. The adjacent electrodes 5 of the two capacitors 1 are joined previously by soldering, etc., at that time, and the two capacitors 1 are unified in parallel beforehand. The electrodes 5 of each capacitor 1 are soldered onto the conductor patterns 3, to which cutouts 3a are formed in response to sections among the adjacent electrodes. A part of a circuit is shaped by the electrodes 5. Since there is no conductor pattern among the electrodes 5 of the two capacitors 1, there is no inductance component of the conductor patterns, also. Accordingly, impedance between the two capacitors 1 is also reduced.

Description

Detailed Description of the Invention

[Object of the Invention]

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric circuit for a leadless component mounting board.

[0003]

2. Description of the Related Art As shown in FIG. 3 (A), conventionally, a plurality of leadless components (capacitors) 1 are mounted on a printed wiring board 2.
When the solder joints 4 are connected in parallel on the conductor pattern 3 of FIG. 3, the electrodes 5 of the leadless components 1 are mutually connected on the conductor pattern 3 formed in series on the substrate surface as shown in FIG. 3B. Soldered separately.

FIG. 3C shows an equivalent circuit of FIG. 3A. The capacitor 1C of the leadless component 1, the inductance 3L and the resistance 3R of the conductor pattern 3, the solder joint 4 and the resistance 45R of the electrode 5 are shown. It consists of and.

[0005]

As shown in the equivalent circuit of FIG. 3C, there are an inductance 3L and a resistance 3R of the conductor pattern 3 between a plurality of leadless components (capacitors) 1. There is a problem that the impedance due to 3L and resistor 3R cannot be ignored.

The present invention has been made in view of the above circumstances, and reduces the impedance between leadless components when a plurality of leadless components are connected in parallel on a conductor pattern of a printed wiring board. The purpose is.

[Constitution of Invention]

[0008]

According to the present invention, a plurality of leadless components 1 are integrated in parallel in an electric circuit in which the leadless components 1 are mounted on a conductor pattern 3 of a printed wiring board 2. The electrodes 5 of the leadless component 1 are formed on the conductor pattern 3 in which the adjacent electrodes 5 of each leadless component 1 are joined together and the notch 3a is formed between the adjacent electrodes 5.
Is soldered, and a part of the circuit is formed by this electrode 5, which is an electric circuit of the leadless component mounting board.

[0009]

In the present invention, since the conductor pattern 3 of the printed wiring board 2 does not exist between the adjacent electrodes 5 of the leadless components 1, the inductance of the interelectrode conductor pattern is eliminated.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the embodiments shown in FIGS.

As shown in FIG. 1A, two leadless components (capacitors) 1 are mounted on a conductor pattern 3 of a printed wiring board 2 by solder joints 4. In that case, the two leadless components 1 are integrated in parallel, and the adjacent electrodes 5 of each leadless component 1 are joined in advance by soldering or the like.

The area between the adjacent electrodes 5 is shown in FIG.
As shown in FIGS. 1A and 1B, the electrode 5 of each leadless component 1 is soldered on the conductor pattern 3 in which the notch 3a is formed, and the electrode 5 forms a part of the circuit. To do.

FIG. 1C shows an equivalent circuit of FIG. 1A. The capacitor 1C of the leadless component 1, the inductance 3L and the resistance 3R of the conductor pattern 3, the solder joint 4 and the resistance 45R of the electrode 5 are shown. And a resistor 1R between leadless parts (between adjacent electrodes).

Comparing the equivalent circuit of FIG. 1C with the equivalent circuit of FIG. 3C, the equivalent circuit of FIG.
Since there is no conductor pattern between the adjacent electrodes 5,
There is no inductance 3L and resistance 3R in the interelectrode conductor pattern. Instead, the equivalent circuit of FIG. 1C has a resistor 1R between leadless components (between adjacent electrodes). The resistance 1R is offset by the resistance 3R of the inter-electrode conductor pattern. Therefore,
The equivalent circuit of FIG. 1C differs from the equivalent circuit of FIG. 3C in that there is no inductance component of the interelectrode conductor pattern.

FIG. 2 (A) shows another embodiment of the present invention, in which three leadless components (capacitors) 1 are integrated in parallel, and between adjacent electrodes 5 of each leadless component 1. The electrodes 5 are joined together by soldering or the like, and the electrodes 5 are soldered on the conductor pattern 3 in which two notches 3a are formed corresponding to the adjacent electrodes 5 as shown in FIG. One electrode 5 forms part of the circuit.

[0016]

According to the present invention, a plurality of leadless components are integrated in parallel, adjacent electrodes of each leadless component are joined together, and a notch is formed correspondingly between the adjacent electrodes. Since the electrodes of the leadless components are soldered on the conductor pattern and a part of the circuit is formed by these electrodes, the inductance between the leadless components mounted in parallel disappears, and the impedance between the leadless components is reduced accordingly. There is an effect that can be reduced.

[Brief description of drawings]

FIG. 1A is a perspective view of an electric circuit of a leadless component mounting board showing an embodiment of the present invention. (B) It is a plan view showing a conductor pattern of the same electric circuit. (C) It is a circuit diagram which shows the equivalent circuit of an electric circuit same as the above.

FIG. 2A is a perspective view of an electric circuit of a leadless component mounting board showing another embodiment of the present invention. (B) It is a plan view showing a conductor pattern of the same electric circuit.

FIG. 3A is a perspective view showing an electric circuit of a conventional leadless component mounting board. (B) It is a plan view showing a conductor pattern of the same electric circuit. (C) It is a circuit diagram which shows the equivalent circuit of an electric circuit same as the above.

[Explanation of symbols]

 1 Leadless parts 2 Printed wiring board 3 Conductor pattern 3a Notch 5 Electrode

Claims (1)

[Claims] 1. An electric circuit in which leadless components are mounted on a conductor pattern of a printed wiring board, a plurality of leadless components are integrated in parallel and adjacent electrodes of each leadless component are joined together, An electrode of a leadless component is soldered on a conductor pattern in which a notch is formed corresponding to the adjacent electrode, and a part of the circuit is formed by this electrode. electric circuit.