JP2017083267A - Electronic circuit and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable evaluation of an electronic circuit without providing a pad exclusive for evaluation.SOLUTION: Of both the electrodes of an electronic device 105, a lower-potential electrode 163 is connected to a first pad 153 and a higher-potential electrode 161 is connected to a second pad 151. The second pad 151 includes a first sub pad 111A and a second sub pad 111B separate from each other in a current direction. The higher-potential electrode 161 is located over the first and second sub pads 111A and 111B, and is connected to one of the first and second sub pads 111A and 111B according to an evaluation purpose when an evaluation is being made.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic circuit, and more particularly to an electronic device capable of evaluating an electronic circuit.

  As a technique related to evaluation of an electronic circuit, for example, a technique disclosed in Patent Document 1 is known. According to Patent Document 1, an inspection probe is connected to a signal pad to inspect a circuit pattern.

Japanese Patent Laid-Open No. 5-26943

  In Patent Document 1, the signal pad is provided only for inspection, and is not necessary except for inspection. Providing such a pad is not preferable from the viewpoint of resource saving, and may also reduce the wiring area. “Inspection” of a circuit pattern is an example of “evaluation” in this specification for an electronic circuit.

  An object of the present invention is to make it possible to evaluate an electronic circuit without providing a pad only for evaluation.

  The electronic circuit includes an electronic circuit board, an electronic device provided on the electronic circuit board, a first pad to which the low potential side electrode of the electronic device is connected, and a second pad to which the high potential side electrode of the electronic device is connected. And a pad. The second pad includes a first subpad and a second subpad spaced in the current direction. In other words, the second pad is divided into a plurality of subpads including the first and second subpads. For such a second pad, the high potential side electrode straddles the first and second subpads.

  When evaluating an electronic circuit, the high potential side electrode need only be connected to one of the first and second subpads, depending on the purpose of the evaluation. After the evaluation, the high potential side electrode is connected across the first and second subpads so that the electronic circuit operates normally. That is, by such connection, the electrically disconnected first and second subpads can be energized.

  The electronic device is not an electronic device provided only for evaluation. Therefore, both the first and second pads are necessary for electronic circuit operation, and are not pads provided only for evaluation. According to the present invention, an electronic circuit can be evaluated without providing a pad only for evaluation.

1 is a schematic diagram of an electronic circuit (after evaluation) according to Example 1. FIG. It is a schematic diagram of the electronic circuit (at the time of evaluation which measures the current which came out of a capacitor) concerning Example 1. It is a schematic diagram of the electronic circuit (at the time of evaluation which measures the current which enters into a capacitor) concerning Example 1. It is a schematic diagram of an example of a circuit diagram. It is a schematic diagram of the board | substrate circuit pattern according to the circuit diagram of FIG. It is a schematic diagram of the principal part of the electronic circuit which concerns on Example 2 (at the time of evaluation which measures the electric current which came out of the capacitor | condenser). It is a schematic diagram of the principal part of the electronic circuit which concerns on Example 3 (at the time of evaluation which measures the electric current which came out of the capacitor | condenser). It is a schematic diagram of the principal part of the electronic circuit (at the time of evaluation which measures the current which enters into a capacitor) concerning Example 4. 10 is a schematic diagram of an electronic circuit according to Embodiment 5. It is a schematic diagram of the principal part of the electronic circuit which concerns on Example 5 (at the time of evaluation which measures the electric current which came out of the capacitor | condenser). It is a schematic diagram of the principal part of the electronic circuit (at the time of evaluation which measures the current which enters into a capacitor) concerning Example 5. FIG. 10 is a schematic diagram of a main part of an electronic circuit according to a sixth embodiment. FIG. 10 is a schematic diagram of a main part of an electronic circuit according to a seventh embodiment.

  Several embodiments will be described below.

  FIG. 1 is a schematic diagram of an electronic circuit (after evaluation) according to the first embodiment.

  The electronic circuit 100 shown in FIG. 1 is an electronic circuit after evaluation, for example, an electronic circuit after circuit constants are determined by evaluation.

  The electronic circuit 100 includes an electronic circuit board (hereinafter referred to as a board) 101. The substrate 101 is electrically connected to a power supply IC (Integrated Circuit) 103, one or a plurality of electronic devices (also referred to as electronic elements), a plurality of pads to which the electronic devices are bonded, and the pads to each other. Wiring and the like are provided. Each pad may be a bonding pad, for example. Each pad is made of, for example, copper, but a metal other than copper or a conductor other than metal may be used instead of or in addition to the metal. Each pad is a square, but a shape other than a square may be adopted.

  The electronic circuit 100 may be referred to as a power supply device including a power supply IC 103 (an example of a power supply circuit). The electronic circuit 100 is provided in an electronic device, for example, and has a function of supplying power to one or more load devices in the electronic device or performing voltage conversion to generate a desired voltage value. At least one load device may be provided in the electronic circuit 100.

  Each of the one or more electronic devices is an electronic device that plays a predetermined role in the electronic circuit operation. Each of the one or more electronic devices is an electronic device that generates a potential difference between both electrodes, such as a capacitor, a diode, a resistor (at least greater than 0Ω), or a varistor. Of the one or more electronic devices that cause a potential difference between the two electrodes, at least one electronic device is determined as the target electronic device according to the evaluation purpose. In the following, among the plurality of pads, the pad to which the low potential side electrode that is the first electrode of the target electronic device is bonded is the first pad, and the high potential side electrode that is the second electrode of the target electronic device. The pad to which is bonded is the second pad. When there are a plurality of target electronic devices, the first pad may be common. The first pad is, for example, a ground pad.

  In this embodiment, the capacitor 105 is an example of the target electronic device. Capacitor 105 smoothes the current from power supply IC 103. For this reason, smoothness is an example of a predetermined role.

  The pad 153 to which the low potential side electrode 163 of the capacitor 105 is bonded is an example of a first pad, and the pad 151 to which the high potential side electrode 161 of the capacitor 105 is bonded is an example of a second pad. The pad 151 includes a first sub pad 111A and a second sub pad 111B that are separated in the current direction. In other words, the pad 151 is divided into a plurality of subpads including the first and second subpads 111A and 111B. Therefore, the pad 151 can be referred to as a “divided pad 151”. Further, the pad 153 can be referred to as a “relative pad 153” because the pad 153 is a pad opposite to the divided pad 151 (a pad facing each other).

  The first subpad 111A is a subpad on the upstream side of the current, and is connected to the power supply IC 103 via, for example, the first wiring 171A. The second subpad 111B is a subpad on the downstream side of the current, and is connected to the load device 180 via, for example, the second wiring 171B. After the evaluation, as shown in FIG. 1, the high-potential side electrode 161 of the capacitor 105 straddles the first and second subpads 111A and 111B. That is, the electrode 161 is bonded to both the first and second subpads. Thereby, it is possible to energize the first and second sub pads 111A and 111B that have been electrically disconnected. That is, in the electronic circuit operation, a current from the power supply IC 103 flows to the load device 180 via the first wiring 171A, the first subpad 111A, the capacitor 105, the second subpad 111B, and the second wiring 171B.

  Among the one or a plurality of electronic devices, at least both electrodes 161 and 163 of the capacitor 105 which is an example of the target electronic device are soldered to the pads 151 and 153, respectively. Soldering is an example of bonding, and bonding is an example of connection between electrodes and pads. Note that both electrodes 161 and 163 may be bonded to the pads 151 and 153 by a conductive adhesive, and in that case, bonding is an example of a connection between the electrode and the pad.

  When evaluating the electronic circuit 100, the high-potential side electrode 161 of the capacitor 105 is connected to only one of the first and second subpads 111A and 111B according to the evaluation purpose.

  FIG. 2 is a schematic diagram when measuring the current output from the capacitor 105 in the evaluation of the electronic circuit 100.

  In order to measure the current output from the capacitor 105, the high potential side electrode 161 is bonded only to the first subpad 111A of the first and second subpads 111A and 111B. The first subpad 111A is connected to the plus terminal 203 of the measuring instrument 201, and the second subpad 111B is connected to the minus terminal 205 of the measuring instrument 201. As a result, the measuring device 201 measures the current output from the capacitor 105. The measuring instrument 201 may be an ammeter, but may be an oscilloscope or a current probe.

  FIG. 3 is a schematic diagram when measuring the current entering the capacitor 105 in the evaluation of the electronic circuit 100.

  In order to measure the current entering the capacitor 105, the high potential side electrode 161 is connected only to the first subpad 111A of the first and second subpads 111A and 111B. The first subpad 111A is connected to the plus terminal 203 of the measuring instrument 201, and the second subpad 111B (or the high potential side electrode 161) is connected to the minus terminal 205 of the measuring instrument 201. As a result, the current entering the capacitor 105 is measured by the measuring instrument 201.

  As described above, according to the present embodiment, the capacitor 105 is one of the electronic devices that play a predetermined role of smoothing in the electronic circuit operation, and is not an electronic device provided only for evaluation. Therefore, any of the pads 151 and 153 to which the electrodes 161 and 163 of the capacitor 105 are bonded is a pad necessary for the electronic circuit operation, and is not a pad provided only for evaluation. According to the present embodiment, the electronic circuit 100 can be evaluated without providing a pad only for evaluation.

  It should be noted that it is not easy for those skilled in the art to employ the divided pad 151 as one of means for evaluating the electronic circuit 100 without providing a pad only for evaluation as in this embodiment. The reason is as follows, for example.

  In general, in the creation of an electronic circuit, a circuit designer first creates a circuit diagram using a circuit design CAD (a tool (for example, software) that supports design of a circuit diagram), and then, based on the created circuit diagram. In addition, the board designer uses the board design CAD to create a circuit pattern of the board (typically, a PCB (Printed Circuit Board)), and such a process is obtained to determine the circuit pattern of the electronic circuit.

  Usually, the circuit designer and the board designer are not the same person. In particular, the cost of the board design CAD is higher than the cost of the circuit design CAD. Therefore, the board design is often outsourced. From such an environment, the board designer creates a circuit pattern of the board according to the created circuit diagram. Specifically, for example, a circuit diagram is imported into the board design CAD, and the board design CAD creates and outputs a board circuit pattern according to the circuit diagram.

In the circuit diagram, a label called “net” is generally assigned. The same net is allocated to the place where the same electric signal flows. Specifically, for example, according to the circuit diagram illustrated in FIG. 4, the current (electric signal) output from the pin 2 of IC ₁ (power supply IC 103) is the electrode 1 (high potential side electrode) of C 1 (capacitor 105). 161) and IC ₂ (load device 108) flow to pin 3, so the same net “A” is assigned to them.

  As described above, the board designer creates the circuit pattern of the board according to the created circuit diagram. Therefore, if the created circuit diagram is the circuit diagram shown in FIG. 4, the substrate circuit pattern shown in FIG. 5 is created. In the created substrate circuit pattern, as shown in FIG. 5, the pad to which the high potential side electrode 161 of the capacitor 105 is bonded is not a divided pad 151 but a normal continuous pad.

  For these reasons, it is not easy for those skilled in the art to employ the divided pad 151 as one of means for evaluating the electronic circuit 100 without providing a pad only for evaluation.

  It is desirable that the first and second subpads 111A and 111B have the same area (“same” may be exactly the same but may be the same). This is because the high potential side electrode 161 is soldered to the first and second sub pads 111A and 111B, for example, by reflow soldering, but if the areas of the first and second sub pads 111A and 111B are the same, the amount of solder Therefore, the melting time is also the same, and as a result, the capacitor 105 is fixed without tilting. In other words, it is possible to reduce the possibility that the time for the solder of the first and second subpads 111A and 111B to melt becomes uneven and the capacitor 105 tilts.

  Example 2 will be described below. At that time, differences from the first embodiment will be mainly described, and description of common points with the first embodiment will be omitted or simplified.

  FIG. 6 is a schematic diagram of the main part of the electronic circuit according to the second embodiment (when evaluating the current output from the capacitor 105).

  In the electronic circuit 600 according to the second embodiment, at least the area of the divided pad 651 out of the divided pad 651 and the relative pad 653 (here, the total area of the first and second subpads 611A and 611B) is other than the capacitor 105. It is larger than the area of a pad (not shown) (ordinary pad) to which the electrode of the electronic device is connected. That is, at least the divided pad 651 may be a wide pad.

  According to the second embodiment, since at least the bonding area of the electrode 161 is large, it is easy to perform evaluation and bonding across the first and second subpads 611A and 611B.

  Also in the second embodiment, it is desirable that the first and second subpads 611A and 611B have the same area.

  Further, the wide pad as in the second embodiment may be employed in any of the third to seventh embodiments described later.

  Example 3 will be described below. At that time, the differences from the first and second embodiments will be mainly described, and the description of the common points with the first and second embodiments will be omitted or simplified.

  FIG. 7 is a schematic diagram of the main part of the electronic circuit according to the third embodiment (when evaluating the current output from the capacitor 105).

  In the electronic circuit 700 according to the third embodiment, the pad to which the high potential side electrode 161 of the capacitor 105 is bonded is a divided pad 751 that is divided so as to cross the current direction diagonally. Therefore, each of the first and second subpads 711A and 711B is a triangle or trapezoid having a right angle. Which of the first and second subpads 711A and 711B has the longer base (the side on the relative pad 753 side) is the purpose of the evaluation, that is, the current flowing out of the capacitor 105 and the current flowing into the capacitor 105 It depends on which one is being measured. When measuring the current output from the capacitor 105, the bottom of the first subpad 711A is longer as shown in FIG.

  Example 4 will be described below. At that time, the differences from the first to third embodiments will be mainly described, and the description of the common points with the first to third embodiments will be omitted or simplified.

  FIG. 8 is a schematic diagram of the main part of the electronic circuit according to the fourth embodiment (during evaluation for measuring the current entering the capacitor 105).

  In the electronic circuit 800, the bottom side of the second subpad 811B is longer than the first and second subpads 811A and 811B of the divided pad 851.

  According to the third and fourth embodiments, depending on the evaluation purpose, since either one of the first and second subpads 711A and 711B (811A and 811B) is longer, the evaluation is easy.

  Further, according to the third and fourth embodiments, the cut pattern of the dividing pad 751 (851) (right diagonally downward direction or left diagonally downward direction), in other words, the first and second subpads 711A and 711B (811A and 811B). Since the base of either of these is longer, it is possible to specify the current direction. For this reason, it is not necessary to look at the circuit diagram to know the current direction.

  In any of the third and fourth embodiments, it is desirable that the first and second subpads 711A and 711B (811A and 811B) have the same area.

  Example 5 will be described below. At that time, the differences from the first to fourth embodiments will be mainly described, and the description of the common points with the first to fourth embodiments will be omitted or simplified.

  FIG. 9 is a schematic diagram of the main part of the electronic circuit according to the fifth embodiment.

  In the electronic circuit 900 according to the fifth embodiment, the dividing pad 951 is a combination of the dividing pad 751 in FIG. 7 and the dividing pad 851 in FIG. That is, the division pad 951 is a pad cut into an X-shape, and thus includes the third and fourth subpads 911C and 911D sandwiched between them in addition to the first and second subpads 911A and 911B.

  FIG. 10 is a schematic diagram when measuring the current output from the capacitor 105 in the evaluation of the electronic circuit 900. FIG. 11 is a schematic diagram when measuring the current entering the capacitor 105 in the evaluation of the electronic circuit 900.

  According to the cut pattern of the divided pad 951, it is easy to evaluate both the current output from the capacitor 105 and the current input to the capacitor 105.

  None of the third and fourth subpads 911C and 911D may be present. However, according to FIGS. 10 and 11, it is preferable that there is a fourth subpad 911D closer to the relative pad, and the third subpad 911C There is no need.

  Example 6 will be described below. At that time, the differences from the first to fifth embodiments will be mainly described, and the description of the common points with the first to fifth embodiments will be omitted or simplified.

  FIG. 12 is a schematic diagram of the main part of the electronic circuit according to the sixth embodiment.

  In the electronic circuit 1200 according to the sixth embodiment, at least one of the first and second subpads 1211A and 1211B of the split pad 1251 has a wedge shape. At least one of the first and second subpads 1211A and 1211B has a shape indicating the current direction. For example, the first subpad 1211 is a triangle such as an isosceles triangle or an equilateral triangle, and the vertex located on the most downstream side in the current direction indicates the current direction. Alternatively, for example, the second subpad 1211 includes a right triangle having a long side close to the relative pad, and the direction of the hypotenuse indicates the current direction.

  According to the sixth embodiment, the current direction can be specified from the shape of at least one of the first and second subpads 1211A and 1211B. For this reason, it is not necessary to look at the circuit diagram to know the current direction.

  Example 7 will be described below. At that time, the differences from the first to sixth embodiments will be mainly described, and the description of the common points with the first to sixth embodiments will be omitted or simplified.

  FIG. 13 is a schematic diagram of the main part of the electronic circuit according to the seventh embodiment.

  In the electronic circuit 1300 according to the seventh embodiment, the cut pattern of the divided pad 1351 is wavy. That is, the cut pattern does not necessarily include a straight line, and at least a part may be a curved line.

  In the divided pad 1351, it is desirable that the areas of the first and second subpads 1311A and 1311B are the same.

  In the seventh embodiment, at least one of the first and second subpads 1311A and 1311B may have a shape indicating the current direction. For example, among the first and second subpads 1311A and 1311B, the first subpad 1311A may include a portion that is longer in the current direction than the second subpad 1311B.

  Although several embodiments have been described above, these are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to these embodiments. That is, the present invention can be implemented in various other forms. For example, the pad to which the high-potential-side electrode 161 of the capacitor 105 is bonded is the first subpad connected to the first wiring (upstream wiring) and the second connected to the second wiring (downstream wiring). If it includes a subpad, it may be divided into N subpads (N is an integer of 2 or more).

100, 600, 700, 800, 900, 1200, 1300: electronic circuit

Claims (6)

An electronic circuit board;
An electronic device provided on the electronic circuit board;
A first pad to which the first electrode of the electronic device is connected;
A second pad to which the second electrode of the electronic device is connected,
The second pad includes a first subpad and a second subpad spaced apart in a current direction,
The second electrode straddles the first and second subpads;
Electronic circuit. The first electrode is a low-potential side electrode of the electronic device, and the second electrode is a high-potential side electrode of the electronic device;
The high potential side electrode is soldered to the first and second subpads,
The first and second subpads have the same area.
The electronic circuit according to claim 1. At least one of the first and second subpads is a shape indicating the current direction.
The electronic circuit according to claim 1 or 2. An area of the second pad is larger than an area of at least one pad to which an electrode of an electronic device other than the target electronic device is connected;
The electronic circuit according to claim 1. The electronic device is an electronic device determined according to an evaluation purpose.
The electronic circuit according to claim 1. An electronic circuit according to any one of claims 1 to 5,
A load device connected to the electronic circuit,
The electronic circuit has a power supply circuit;
The first subpad is connected to the power supply circuit via a first wiring;
The second subpad is connected to the load device via a second wiring;
Electronics.

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