JP2021057407A - Electronic circuit device - Google Patents

Abstract

To provide an electronic circuit device that is provided with a shunt resistance and electrification patterns on both top and reverse surfaces of a substrate, and that suppresses the shunt resistance and the electrification patterns from rising in temperature.SOLUTION: The present electronic circuit device 10 is characterized in that a first electrification pattern 13 and a second electrification pattern 14 on both surfaces of a substrate 12 connected to a shunt resistance 11 are connected by a conductor 32 and a through conductor 21 electrically connecting an electronic component 31 mounted on the substrate 12. The through conductor 21 is provided at a position from an electrode 11B of the shunt resistance 11 to the conductor 32. Here, R3 and R4 are less than 1/10 time as large as R1, R2, where R1, R2 represent wiring resistance values of the first electrification pattern 13 and second electrification pattern 14 from the center of a connection part for the through conductor 21 to the center of a fitting part for the conductor 32, R4 represents a wiring resistance value of the first electrification pattern 13 from an electrode connection part 17 for the electrode 11B to the center of the through conductor 21, and R3 represents a wiring resistance value of the through conductor 21.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to an electronic circuit device incorporating a shunt resistor.

Conventionally, in an inverter device or the like, an electronic circuit device including a current detection circuit incorporating a flat plate-shaped surface mount type shunt resistor has been used. In this electronic circuit device, the amount of heat generated by the shunt resistor increases as the current capacity of the inverter device increases. Therefore, in the current detection of the large-capacity inverter, the temperature rise of the shunt resistor and the energization pattern around it has become a problem. The shunt resistor is a high heat generating component and at the same time has a limited heat dissipation path. The heat dissipation path of the shunt resistor is a heat dissipation path that directly dissipates heat from the shunt resistor itself to the air, and a heat dissipation path that transfers heat from the shunt resistance to the energization pattern and dissipates heat from the energization pattern to the air.

For example, Patent Document 1 is known as having a heat dissipation path that directly dissipates heat from a shunt resistor to air. In Patent Document 1, a connecting member is provided between the shunt resistor and the energization pattern so that the shunt resistor floats in the air, and heat is dissipated directly from the shunt resistor itself to the air. For example, Patent Document 2 is known as having a heat dissipation path that transfers heat from a shunt resistor to an energization pattern and dissipates heat from the energization pattern to air. In Patent Document 2, an energization pattern is formed on the surface of a substrate, and a through hole penetrating the substrate and the energization pattern is provided in a predetermined region of the energization pattern to increase the energization pattern in contact with air and the surface area of the substrate. Is.

International Publication No. 2014/41756 Japanese Unexamined Patent Publication No. 2016-21975

The electronic circuit device described in Patent Document 1 has a problem that an additional mounting member is required and the manufacturing man-hours increase. The electronic circuit device described in Patent Document 2 has a problem that the strength of the upper substrate is weakened because additional processing is required.

The present disclosure is to provide an electronic circuit device in which a shunt resistor and an energization pattern are provided on both the front and back surfaces of a substrate, and the temperature rise of the shunt resistor and the energization pattern is suppressed.

The electronic circuit device according to the first aspect includes a substrate, a shunt resistor provided with an electrode, and a first energization pattern provided so as to make surface contact with the electrode on a surface of the substrate facing the shunt resistance. , A second energization pattern provided on the other surface of the substrate, a conductor for electrically connecting electronic components mounted on the substrate, and a through conductor provided so as to penetrate the substrate. The conductor is inserted into a through hole provided in the substrate and joined to the first energization pattern and the second energization pattern, and the through conductor is said from the position of the electrode. In the first energization pattern path to the position of the conductor, the first energization pattern and the second energization pattern are provided so as to be connected to each other, and the center of the connection portion with the through conductor in the first energization pattern. The wiring resistance of the portion from to the center of the mounting portion of the conductor is R1, and the wiring resistance of the portion from the center of the connecting portion with the penetrating conductor to the center of the mounting portion of the conductor in the second energization pattern. Is R2, the wiring resistance of the through conductor is R3, and the wiring resistance from the center of the electrode connection portion with the electrode to the center of the through conductor in the first energization pattern is R4. It is formed so as to be less than the value of R1 × 1/10 and less than the value of R2 × 1/10, respectively.

According to this configuration, the wiring resistance connecting the shunt resistor and the first energization pattern and the second energization pattern is negligible except for the wiring resistance of the first energization pattern and the second energization pattern. As a result, the heat generated by the shunt resistor can be satisfactorily transferred from the shunt resistor to the first energization pattern and the second energization pattern. Further, the current flowing through the first energization pattern and the second energization pattern and the amount of heat transfer can be equalized, and the equalization of the heat generation amount and the heat dissipation amount in both patterns can be improved. As a result, it is possible to suppress the temperature rise of the shunt resistance, the first energization pattern, and the second energization pattern.

The electronic circuit device according to the second aspect is configured to be able to detect a current of 2 A or more.
According to this configuration, it can be applied to a power supply circuit of a large-capacity device such as an air conditioner or a refrigerator / freezer.

According to the electronic circuit device according to the third aspect, the dimension of the electrode connection portion that is perpendicular to the current flow direction in the first energization pattern and that is along the substrate surface is the dimension of the electrode connection portion. With respect to the first energization pattern, the width dimension W is defined as the current flow direction in the first energization pattern and the dimension in the direction perpendicular to the substrate surface is the thickness H of the first energization pattern. The penetrating conductor is formed so that S> W × H × 30 is established when the cross-sectional area of the cross section parallel to the substrate surface is the cross-sectional area S of the penetrating conductor.

According to this configuration, H is usually about 0.1 mm, and the conductivity and heat transfer coefficient of the material of the first energization pattern and the through conductor are usually about the same. Further, even if the width dimension of the first energization pattern is increased, the reduction of the wiring resistance of the first energization pattern is limited to about 1/3. Therefore, in order to realize that R3 is equal to or less than the value of R1 × 1/10 and less than or equal to the value of R2 × 1/10, it may be configured as S> W × H × 30, and it is also managed as S> W. can do. By such management, it is possible to suppress the temperature rise of the shunt resistance, the first energization pattern and the second energization pattern.

According to the electronic circuit device according to the fourth aspect, the through conductor is provided so that at least a part of the end face on the first energization pattern side overlaps with the position of the electrode when viewed from the direction perpendicular to the substrate surface. Has been done.

According to this configuration, in the combination of the first energization pattern and the second energization pattern, the wiring resistors R3 and R4 on the electric equivalent circuit can be reduced, and the heat transfer resistance from the shunt resistance to the second energization pattern can be reduced. Can also be made smaller.

According to the electronic circuit device according to the fifth aspect, the through conductor is provided so that the entire end surface on the first energization pattern side overlaps with the position of the electrode when viewed from the direction perpendicular to the substrate surface. ing.

According to this configuration, in the combination of the first energization pattern and the second energization pattern, the wiring resistors R3 and R4 on the electric equivalent circuit can be made smaller, and the heat transfer from the shunt resistance to the second energization pattern can be made. The resistance can also be smaller.

According to the electronic circuit apparatus according to the sixth aspect, the through conductor includes a conductor portion inserted into a through hole penetrating the substrate, the first energization pattern, and the second energization pattern, and the conductor portion is It is soldered to the first energization pattern and the second energization pattern.

According to the electronic circuit apparatus according to the seventh aspect, the through conductor is provided with a protrusion for retaining at one of the first energization pattern or the end portion protruding from the second energization pattern in the conductor portion. There is.

According to this configuration, since the through conductor is provided with a protrusion for retaining at one end of the end portion protruding from the energization pattern, it is possible to suppress the lifting or falling of the through conductor at the time of soldering.

The circuit diagram which shows the schematic structure of the power conversion apparatus which includes the electronic circuit apparatus which concerns on 1st Embodiment. Cross-sectional view of the vicinity of the shunt resistor in the electronic circuit device. Electrical equivalent circuit diagram of the electronic circuit device. A plan view of the shunt resistor in FIG. 2 as viewed from a direction perpendicular to the substrate surface. Enlarged view around the shunt resistor in FIG. The graph which showed the change of the wiring resistance of the 1st energization pattern when the width dimension of the 1st energization pattern of FIG. 5 was increased. Sectional drawing in the vicinity of a shunt resistor in the electronic circuit apparatus which concerns on a reference example. It is explanatory drawing which showed the operation effect of the electronic circuit apparatus which concerns on 1st Embodiment by comparison with the electronic circuit apparatus which concerns on a reference example, (a) is a calorific value comparison diagram in an energization pattern, (b) is an energization pattern Maximum temperature comparison diagram in. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the second embodiment. FIG. 9 is a plan view seen from a direction perpendicular to the substrate surface. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the third embodiment. FIG. 11 is a plan view seen from a direction perpendicular to the substrate surface. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the fourth embodiment. FIG. 13 is a plan view seen from a direction perpendicular to the substrate surface. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the fifth embodiment. FIG. 14 is a plan view seen from a direction perpendicular to the substrate surface. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the sixth embodiment. FIG. 17 is a plan view seen from a direction perpendicular to the substrate surface. FIG. 5 is a cross-sectional view of the vicinity of a shunt resistor in the electronic circuit device according to the seventh embodiment. FIG. 5 is a cross-sectional view of the vicinity of the shunt resistor in the electronic circuit device according to the modified example.

Hereinafter, the electronic circuit device according to the embodiment will be described. It should be noted that the present disclosure is not limited to the examples described below, and is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims. To.

(First Embodiment)
A schematic configuration of the power conversion device 1 including the electronic circuit device 10 according to the first embodiment will be described with reference to FIG.

The power conversion device 1 includes a converter unit 2 that converts an AC voltage into a DC voltage, and an inverter unit 3 that converts the DC voltage converted by the converter unit 2 into a three-phase AC voltage. The converter unit 2 is connected to an AC power supply (not shown), and the inverter unit 3 is connected to the motor 4 as a load. The motor 4 is an embedded magnet synchronous motor, and is used for driving a compressor such as an air conditioner or a refrigerator.

The converter unit 2 is a rectifier circuit that converts an input AC voltage from an AC power supply (not shown) into a DC voltage. The converter unit 2 is electrically connected to the inverter unit 3 by the first wiring L1 and the second wiring L2. Although not particularly shown, the converter unit 2 is provided with a plurality of switching elements, and is configured so that a rectifying operation from an AC voltage to a DC voltage is performed by the switching operation of the switching elements.

The inverter unit 3 has a plurality of (6) switching elements 5, and is configured to convert the DC voltage output from the converter unit 2 into a three-phase AC voltage by the switching operation of the switching elements 5. ing.

Specifically, the inverter unit 3 has six switching elements 5, which are connected by a three-phase bridge. That is, in the inverter unit 3, switching legs 7 composed of two switching elements 5 connected in series with each other are connected in parallel, and an intermediate point of each switching leg 7 is connected to three phases of the motor 4.

Each switching element 5 is composed of, for example, an IGBT (insulated gate type bipolar transistor) as shown in FIG.
The switching element 5 may be a MOSFET of a unipolar transistor or the like as long as it can perform a switching operation. A diode 6 is provided in antiparallel to each of the switching elements 5.

The power conversion device 1 is provided with an electronic circuit device 10 including a shunt resistor 11 in the first wiring L1 which is a connection portion between the converter unit 2 and the inverter unit 3.
The electronic circuit device 10 detects the current flowing through the shunt resistor 11 by the current detection circuit 8 and sends the output signal to the controller 9 to detect the current flowing through the motor 4 connected to the inverter unit 3. The electronic circuit device 10 is used in a drive circuit of an inverter type compressor in an air conditioner, a refrigerator, or the like, and is configured to be capable of detecting a current of 2 A or more.

The controller 9 is configured to output a control signal (PWM signal) for controlling the operation of each switching element 5 of the inverter unit 3 based on the current value detected by the current detection circuit 8.

Next, the configuration of the electronic circuit device 10 will be described.
As shown in FIG. 2, in the electronic circuit device 10, the shunt resistor 11 for detecting the current flowing through the motor 4, the substrate 12 on which the shunt resistor 11 is mounted, and the first energization pattern 13 for connecting the shunt resistor 11 are connected. It has a second energization pattern 14, a first current detection pattern 15, a second current detection pattern 16, and the like.

The shunt resistor 11 has a resistor 11A formed in a thin film shape and an electrode 11B for connecting to the first energization pattern 13.
The resistor 11A is reinforced by a resistance base material formed of a highly rigid material such as a ceramic material such as alumina. The electrodes 11B are provided at both lower ends of the resistor 11A. The shunt resistor 11 is surface-mounted on the substrate 12 by soldering the electrodes 11B at both lower ends to the first energization pattern 13.

The substrate 12 is a glass cloth glass non-woven composite base material called CEM-3 (Composite epitaxial material-3), an epoxy resin copper-clad laminate, or a heat-resistant glass called FR-4 (Flame retardant-4). It is made of a material such as a cloth-based epoxy resin copper-clad laminate and is formed in a flat plate shape.

The first energization pattern 13 and the second energization pattern 14 constitute the first wiring L1 that connects the shunt resistor 11 to the inverter unit 3 and the converter unit 2. The first energization pattern 13 and the second energization pattern 14 are made of a conductive material such as copper, aluminum or an alloy thereof. Further, the first current detection pattern 15 and the second current detection pattern 16 are for detecting the current of the shunt resistor 11, and form a circuit for connecting the electrode 11B of the shunt resistor 11 and the current detection circuit 8. doing. The first current detection pattern 15 and the second current detection pattern 16 are made of the same conductive material as the first energization pattern 13 and the second energization pattern 14, such as copper, aluminum, or an alloy thereof.

The first energization pattern 13 is a pattern provided on the first surface 12a of the substrate 12, and the second energization pattern 14 is a pattern provided on the second surface 12b of the substrate 12. In this specification, the first surface 12a of the substrate 12 refers to the surface on the shunt resistor 11 side, and the second surface 12b of the substrate 12 refers to the surface of the substrate 12 opposite to the first surface 12a.

The first energization pattern 13 is provided on both sides of the shunt resistor 11 in a separated state, and the first energization pattern 13 is the first energization pattern 13a on the inverter portion 3 side (that is, on the right side in the drawing). And the first energization pattern 13b on the converter unit 2 side (that is, on the left side in the drawing). The second energization pattern 14 is formed on the second surface 12b below the drawing of the substrate 12, and is formed on the second energization pattern 14a on the inverter portion 3 side (that is, on the right side in the drawing) and the converter portion 2 side. It is composed of the second energization pattern 14b (that is, on the left side of the drawing).

The first energization pattern 13a and the second energization pattern 14a in this disclosure example are symmetrically arranged on both sides of the first surface 12a and the second surface 12b of the substrate 12 on the right side of the drawing of the shunt resistor 11. Therefore, they are formed to be substantially the same size. The first energization pattern 13a and the second energization pattern 14a form a first wiring L1 (see FIG. 1) located between the electrode 11B of the shunt resistor 11 and the inverter unit 3.

Similarly, the first energization pattern 13b and the second energization pattern 14b in this disclosure example are symmetrically arranged on both the first surface 12a and the second surface 12b of the substrate 12 on the left side of the drawing of the shunt resistor 11. They are formed to be substantially the same size. The first energization pattern 13b and the second energization pattern 14b form a first wiring L1 (see FIG. 1) located between the electrode 11B of the shunt resistor 11 and the converter unit 2.

Next, as a structure around the shunt resistor 11, the structure of the connecting portion between the shunt resistor 11 and the first energization pattern 13 and the second energization pattern 14 will be described in more detail.
In this description, the configurations of the first current detection pattern 15 and the second current detection pattern 16 will be omitted.

In the electronic circuit device 10 of the present disclosure, the structure around the shunt resistor 11 is basically configured symmetrically on both the left and right sides of the shunt resistor 11 as shown in FIG. Therefore, unless otherwise specified, the description around the shunt resistor 11 in the first embodiment and the description around the shunt resistor 11 in the second and subsequent embodiments will be described using only the right side as a representative example instead of the explanations on both the left and right sides. It shall be.

Further, in the present specification, when the term is simply referred to as the first energization pattern 13, the first energization patterns 13a and 13b are referred to without distinction, or these are collectively referred to. Similarly, in the present specification, when the second energization pattern 14 is simply referred to, the second energization patterns 14a and 14b are referred to without distinction, or these are collectively referred to. Therefore, in the following description on the right side of the drawing (including the description after the second embodiment), when the first energization pattern 13a and the second energization pattern 14a are referred to, the first energization pattern 13 and the second energization pattern are simply referred to. It shall be referred to as 14.

As shown in FIG. 2, the first energization pattern 13 and the second energization pattern 14 are connected by a through conductor 21 at an end near the electrode 11B of the shunt resistor 11.
The through conductor 21 is a conductor that connects the first energization pattern 13 and the second energization pattern 14. The through conductor 21 has a reduced wiring resistance and is formed of a copper plug. The through conductor 21 is embedded in a through hole 22 formed in the substrate 12. Although only one through conductor 21 is shown in FIG. 2, it may be composed of a plurality of through conductors 21.

After the through conductor 21 is embedded in the substrate 12, the first energization pattern 13 and the second energization pattern 14 are attached to the surface of the substrate 12 by vapor deposition so as to cover the end surface of the through conductor 21. As a result, the wiring resistance of the connection portion between the through conductor 21 and the first energization pattern 13 and the second energization pattern 14 is reduced.

Further, the first energization pattern 13 and the second energization pattern 14 are connected by a conductor 32 for electrically connecting the electronic component 31 at a position away from the through conductor 21. In FIG. 2, the conductor 32 that electrically connects the electronic component 31 is the two lead terminals of the electronic component 31 in this embodiment.

As shown in FIG. 2, the two conductors 32 are separately inserted into the through holes 33 and soldered. The through hole 33 is a so-called through hole in which a copper-plated layer 33a is provided on the inner surface. The gap between the copper-plated layer 33a of the through hole 33 and the conductor 32 is filled with the solder 34 at the time of soldering. Therefore, the wiring resistance of the conductor 32 is negligible when compared with the wiring resistance of the first energization pattern 13 and the second energization pattern 14. In the present embodiment, the conductor 32 that electrically connects the electronic component 31 may be a conducting wire that electrically connects the electronic component 31 instead of the lead terminal.

FIG. 3 shows an electrical equivalent circuit around the shunt resistor 11.
The wiring resistors R1 to R4 in FIG. 3 are shown in FIG. 2 so that the target portion and the wiring resistance of the portion can be compared and understood. That is, the wiring resistance R1 is the wiring resistance of the portion of the first energization pattern 13 from the center of the connection portion with the through conductor 21 to the center of the mounting portion of the conductor 32. The wiring resistance R2 is the wiring resistance of the portion of the second energization pattern 14 from the center of the connection portion with the through conductor 21 to the center of the mounting portion of the conductor 32. The wiring resistance R3 is the wiring resistance of the through conductor 21. The wiring resistor R4 is a wiring resistor from the center of the electrode connecting portion 17 with the electrode 11B in the first energization pattern 13 to the center of the through conductor 21. In this case, the wiring resistor R1 and the wiring resistor R2 generally have the same dimensions and the same structure, and are considered to be substantially the same because they are made of the same material.

The wiring resistance of the portion connecting the first energization pattern 13 and the second energization pattern 14 by the conductor 32 for electrically connecting the electronic component 31 has a structure generally generally joined, and the first 1 Since it is smaller than the wiring resistance R1 and the wiring resistance R2 of the energization pattern 13, it is ignored in the electrical equivalent circuit of FIG.

The electronic circuit device 10 of the present disclosure is compared with the wiring resistor R1 and the wiring resistor R2 in order to allow a substantially uniform current to flow through the first energization pattern 13 and the second energization pattern 14 in such a configuration. The wiring resistance R3 and the wiring resistance R4 are set to be minute. That is, in the electronic circuit device 10 of the present disclosure, R3 <R1 / 10 and R4 <R1 / 10 are set. Further, in the electronic circuit device 10 of the present disclosure, since the first energization pattern 13 and the second energization pattern 14 have the same size and are formed of the same material, R1 and R2 are substantially the same.

4 and 5 are diagrams for explaining the dimensions for realizing R3 <R1 / 10.
In FIGS. 4 and 5, W refers to the width dimension of the electrode connecting portion 17 in which the first energization pattern 13 and the electrode 11B of the shunt resistor 11 are surface-connected. The width dimension W of the electrode connecting portion 17 is a dimension perpendicular to the current flow direction D (see FIGS. 1 and 4) in the first energization pattern 13 and in a direction along the surface of the substrate 12. In this disclosure example, the width dimension W of the electrode connecting portion 17 is smaller than the width dimension Wp of the first energization pattern 13.

Here, in the first energization pattern 13, the dimension in the direction perpendicular to the current flow direction D in the first energization pattern 13, that is, the width dimension is Wp, and the thickness dimension is H. On the other hand, the second energization pattern 14 has the same size as the first energization pattern 13 and is formed at a position symmetrical with the first energization pattern 13. Therefore, the dimension in the direction perpendicular to the current flow direction D in the second energization pattern 14, that is, the width dimension is Wp, and the thickness dimension is H.

The width dimension W of the electrode connecting portion 17, the width dimension Wp and the thickness dimension H of the first energization pattern 13 and the second energization pattern 14 are expressed in mm units, respectively. The cross-sectional area S of the through conductor 21 is expressed in square mm units.

By the way, the thickness dimension H of the first energization pattern 13 and the second energization pattern 14 is usually 0.1 mm.
Further, the wiring resistance R1 of the first energization pattern 13 and the wiring resistance R2 of the second energization pattern 14 have a larger width dimension Wp of the first energization pattern 13 and the second energization pattern 14 than the width dimension W of the electrode connection portion 17. Then, it is analytically confirmed that the amount is reduced to about 1/3 of the case of W = Wp. FIG. 6 is data showing this. In FIG. 6, the horizontal axis is Wp / W, and the vertical axis is the resistivity. Here, the resistivity is defined as the resistance value of the first energization pattern 13 when W = Wp is set as the reference value 1, and the resistance value of the first energization pattern 13 when Wp / W is changed is the reference value 1. It is shown by the resistance ratio to. As can be seen, even if the width dimension Wp of the first energization pattern 13 is increased with respect to the width dimension W of the electrode connection portion 17, the wiring resistance is reduced to only about 1/3. FIG. 6 shows the first energization pattern, but it goes without saying that the same applies to the second energization pattern 14.

In this way, H is generally 0.1 mm, and considering that R1 becomes 1/3 if Wp is increased, S> W × H × 30 is set. In this way, R3 <R1 / 10 can be maintained even when the width dimension Wp of the first energization pattern 13 and the second energization pattern 14 is sufficiently larger than the width dimension W of the electrode connecting portion 17. Further, in this case, as described above, the thickness H of the first energization pattern 13 and the second energization pattern 14 is 0.1 mm, the width dimension Wp of the energization pattern is increased, and the wiring resistance R1 is lowered to 1/3. If so, R3 <R1 / 10 can be retained by setting S> W.

In the above description, it is specifically explained that the wiring resistance of the conductor 32 is neglected because it is smaller than the wiring resistance R1 of the first energization pattern 13 and the wiring resistance R2 of the second energization pattern 14. To do. For example, the wiring resistance value of two 0.65 mm square lead terminals is 4.0 × 10 ^-5 Ω or less. On the other hand, the width dimension W of the electrode connecting portion 17 is 10 mm, the thickness H of the first energization pattern 13 and the second energization pattern 14 is 50 μm, respectively, and the width dimension Wp of the first energization pattern 13 and the second energization pattern 14 is further set. When each is 50 mm, the wiring resistance R1 of the first energization pattern 13 and the wiring resistance R2 of the second energization pattern 14 are approximately 1.7 × 10 ^-3 Ω. Further, even if the width dimension Wp of the first energization pattern 13 and the second energization pattern 14 is increased, the wiring resistors R1 and R2 are reduced to only about 1/3 as shown in FIG. Therefore, the wiring resistance of the conductor 32 is always one digit or more smaller than the wiring resistance R1 of the first energization pattern 13 and the wiring resistance R2 of the second energization pattern 14.

(Operation of the first embodiment)
Hereinafter, the operation of the electronic circuit device 10 according to the first embodiment will be described.
In the electronic circuit device 10 of the present disclosure, the wiring resistors R4 and R3 are negligibly small as compared with the wiring resistors R1 and R2 of the first energization pattern 13 and the second energization pattern 14. Further, since the first energization pattern 13 and the second energization pattern 14 have the same specifications, the wiring resistance R1 of the first energization pattern 13 and the wiring resistance R2 of the second energization pattern 14 are substantially the same. Therefore, the wiring resistance R4 + R1 of the path flowing through the first energization pattern 13 and the wiring resistance R4 + R3 + R2 of the path flowing through the second energization pattern 14 are substantially the same.

As a result, the current flowing through the first energization pattern 13 and the current flowing through the second energization pattern 14 are substantially the same, so that the amount of heat generated in the first energization pattern 13 and the second energization pattern 14 is the same.

Also, as is known from Wiedemann-Franz's law, there is a proportional relationship between the electrical conductivity and thermal conductivity of metals. Therefore, if the wiring resistance R3 and the wiring resistance R4 are reduced, the electric conductivity is increased and the heat conduction performance is improved, so that the heat conduction from the shunt resistor 11 to the first current-carrying pattern 13 and the second current-carrying pattern 14 is good. Become. The broken line in FIG. 2 indicates the flow direction of heat conduction. At the same time, by reducing the wiring resistance R3 and the wiring resistance R4, the heat transfer resistance from the shunt resistor 11 to the first energization pattern 13 and the second energization pattern 14 is substantially made uniform, so that the shunt resistance 11 to the first The amount of heat transferred to the energization pattern 13 and the second energization pattern 14 is made uniform.

FIG. 8 shows a comparison between the electronic circuit device 10 of the present disclosure and the reference example with respect to the calorific value and the maximum temperature in the first energization pattern 13 and the second energization pattern 14. As shown in FIG. 7, the reference example referred to here is a through conductor 21 in the present disclosure replaced with a via 41 which is generally used as a hole into which a terminal of an electronic component is not inserted. The reference example of FIG. 7 is the same as that of the present disclosure except for the via 41, and the same parts as those of the present disclosure are designated by the same reference numerals and the description thereof will be omitted.

In the electronic circuit device 10 according to the first embodiment, as can be seen from the above description, the wiring resistance and the heat transfer resistance of the circuit connected from the shunt resistor 11 to the first energization pattern 13 and the second energization pattern 14 are reduced. As a result, the current values flowing through the first energization pattern 13 and the second energization pattern 14 are equalized. Further, the heat transfer performance from the shunt resistor 11 to the first energization pattern 13 and the second energization pattern 14 is improved, and the amount of heat transfer to both energization patterns is equalized. As a result, as shown in FIG. 8A, in the reference product, the calorific value of the first energization pattern 13 was larger than the calorific value of the second energization pattern 14, but that of the present disclosure. Then, the calorific value of both energization patterns is made uniform. In addition, the total calorific value in both energization patterns is also reduced. Further, as shown in FIG. 8B, the maximum temperature in both energization patterns becomes equal and the temperature is lowered. At the same time, the maximum temperature of the shunt resistor 11 is also lowered.

(Effect of the first embodiment)
Since the electronic circuit device 10 of the first embodiment is configured as described above, the following effects can be obtained.

(1-1) With respect to the wiring resistors R1 to R4, R1 and R2 are made substantially the same so that R3 <R1 / 10 and R4 <R1 / 10 are established. Therefore, the current values flowing through the first energization pattern 13 and the second energization pattern 14 are made uniform, and the heat transfer from the shunt resistor 11 to the first energization pattern 13 and the second energization pattern 14 is improved and equalized. Will be done. As a result, it is possible to suppress the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14.

(1-2) When the cross-sectional area S of the through conductor 21, the width dimension W of the electrode connecting portion 17, and the thickness H of the first energization pattern 13 and the second energization pattern 14 are set, S> W × H × 30 is established. It may be formed so as to be performed, and it can be managed as S> W.

(1-3) Since the electronic circuit device 10 is configured to be able to detect a current of 2 A or more, it can be applied to a power supply circuit of a large-capacity device such as an air conditioner or a refrigerator / freezer.
(Second Embodiment)
Next, the electronic circuit device 10 according to the second embodiment will be described with reference to FIGS. 9 and 10.

The electronic circuit device 10 according to the second embodiment is the one in which the position of the through conductor 21 is changed in the first embodiment. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As can be seen from FIGS. 9 and 10, the through conductor 21 in the second embodiment is about half of the end surface of the through conductor 21 on the first energization pattern 13 side when viewed from the direction perpendicular to the first surface 12a of the substrate 12. Is provided so as to overlap the position of the electrode 11B of the shunt resistor 11. Other configurations such as the through conductor 21 and the through hole 22 are the same as those in the first embodiment.

Since the electronic circuit device 10 according to the second embodiment is configured as described above, the same effects as those of (1-1) to (1-3) according to the first embodiment can be obtained, and the following can be obtained. It is also possible to play the effect of.

(2-1) In the combination of the first energization pattern 13 and the second energization pattern 14, the wiring resistance R3 and the wiring resistance R4 on the electric equivalent circuit can be reduced, and the shunt resistance 11 to the second energization pattern 14 can be reduced. The heat transfer resistance to is also reduced. As a result, the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14 can be further suppressed.

(Third Embodiment)
Next, the electronic circuit device 10 according to the third embodiment will be described with reference to FIGS. 11 and 12.

The electronic circuit device 10 according to the third embodiment is formed by forming the through conductor 21 in the second embodiment so as to be composed of a plurality of divided through conductors 21a. The same parts as those in the second embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As can be seen from FIG. 12, the through conductor 21 is composed of three divided through conductors 21a in the third embodiment, although it was one in the second embodiment. That is, the through conductor 21 in the third embodiment is composed of three divided through conductors 21a arranged in a straight line in the direction of the width dimension W of the electrode connecting portion 17. Each of the divided through conductors 21a is embedded in the substrate 12 by the same structure as the through conductor 21 in the second embodiment, and about half of each end face on the first energization pattern 13 side is the electrode 11B of the shunt resistor 11. It is provided so as to overlap with the position of.

Since the width dimension W of the electrode connecting portion 17 in the third embodiment is substantially the same as that in the second embodiment, the cross-sectional area Sa of each divided through conductor 21a in the third embodiment is the second embodiment. It is smaller than the cross-sectional area S of the penetrating conductor 21 of. However, the total cross-sectional area of the three divided penetrating conductors 21a, that is, the cross-sectional area S of the penetrating conductor 21 in the third embodiment is larger than the cross-sectional area S of the penetrating conductor 21 in the second embodiment.

Since the electronic circuit device 10 according to the third embodiment is configured as described above, the electronic circuit devices 10 according to the first embodiment (1-1) to (1-3) and the second embodiment (2-). The same effect as 1) can be achieved. In addition, the electronic circuit device 10 according to the third embodiment can also exert the following effects.

(3-1) The cross-sectional area S of the penetrating conductor 21, which is the sum of the cross-sectional areas Sa of the divided penetrating conductors 21a, is larger than the cross-sectional area S of the penetrating conductor 21 in the second embodiment. Therefore, in the third embodiment, in the combination of the first energization pattern 13 and the second energization pattern 14, the wiring resistance R3 and the wiring resistance R4 on the electric equivalent circuit, and the shunt resistance 11 to the second energization pattern 14 are transferred. The heat transfer resistance can be reduced. As a result, the electronic circuit device 10 according to the third embodiment can further suppress the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14.

(Fourth Embodiment)
Next, the electronic circuit device 10 according to the fourth embodiment will be described with reference to FIGS. 13 and 14.

The electronic circuit device 10 according to the fourth embodiment is the one in which the position of the through conductor 21 is changed in the third embodiment. The same parts as those in the third embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As can be seen from FIGS. 13 and 14, the penetrating conductor 21 in the fourth embodiment is composed of three split penetrating conductors 21a like the penetrating conductor 21 in the third embodiment. However, with respect to the three divided penetrating conductors 21a, the entire end surface of all three divided penetrating conductors 21a on the first energization pattern 13 side is the position of the electrode 11B when viewed from the direction perpendicular to the first surface 12a of the substrate 12. It is provided at an overlapping position. The configuration other than the position of the split through conductor 21a is the same as that of the third embodiment.

Since the electronic circuit device 10 according to the fourth embodiment is configured as described above, the effects of (1-1) to (1-3) according to the first embodiment and (2-) according to the second embodiment. The effect of 1) and the effect of (3-1) according to the third embodiment can be exhibited. In addition, the following effects can be achieved.

(4-1) Since the entire end face of all three divided through conductors 21a on the first energization pattern 13 side is provided so as to overlap the position of the electrode 11B of the shunt resistor 11, the wiring resistance R4 on the electrical equivalent circuit is small. Become. As a result, the heat transfer resistance from the shunt resistor 11 to the second energization pattern 14 is further reduced, and the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14 can be further suppressed. it can.

(Fifth Embodiment)
Next, the electronic circuit device 10 according to the fifth embodiment will be described with reference to FIGS. 15 and 16.

The electronic circuit device 10 according to the fifth embodiment is obtained by changing the number and shape of the through conductors 21 in the fourth embodiment. The same parts as those in the fourth embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As can be seen from FIGS. 15 and 16, the penetrating conductor 21 in the fourth embodiment is composed of one penetrating conductor 21 unlike that of the third embodiment. Further, unlike those of the first to fourth embodiments, the through conductor 21 in the fourth embodiment is formed in a rectangular parallelepiped shape long in the width dimension W of the electrode connecting portion 17. Therefore, the cross-sectional shape of the through hole 22 in which the through conductor 21 is embedded is also formed in a rectangular shape. Further, the through conductor 21 in the fifth embodiment is the entire end surface of the through conductor 21 on the first energization pattern 13 side when viewed from the direction perpendicular to the first surface 12a of the substrate 12, as in the case of the fourth embodiment. Is provided at a position overlapping the position of the electrode 11B. Further, the through conductor 21 in the fifth embodiment is formed so that the cross-sectional area S of the through conductor 21 is larger than that in the case of the fourth embodiment.

Since the electronic circuit device 10 according to the fifth embodiment is configured as described above, the effects of (1-1) to (1-3) according to the first embodiment and (2-) according to the second embodiment. The effect of 1) and the effect of (4-1) according to the fourth embodiment can be exhibited. In addition, the following effects can be achieved.

(5-1) Since the cross-sectional area S of the through conductor 21 is formed larger than that in the fourth embodiment, the wiring resistance R3 on the electrical equivalent circuit becomes smaller. As a result, the heat transfer resistance from the shunt resistor 11 to the second energization pattern 14 is further reduced, and the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14 can be further suppressed. it can.

(Sixth Embodiment)
Next, the electronic circuit device 10 according to the sixth embodiment will be described with reference to FIGS. 17 and 18.

The electronic circuit device 10 according to the sixth embodiment is a modification of the structure and mounting structure of the through conductor 21 in the first embodiment. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As can be seen from FIGS. 17 and 18, the through conductor 21 in the sixth embodiment includes a plate-shaped conductor portion 211. Both ends of the conductor portion 211 are formed so as to protrude from the first energization pattern 13 and the second energization pattern. At the end of the conductor portion 211 on the first energization pattern 13 side, a flat protrusion 212 overhanging in the longitudinal direction of the first energization pattern 13 is formed. As shown in FIG. 18, the plate-shaped conductor portion 211 and the flat protruding portion 212 are formed in a rectangular shape when viewed from a direction perpendicular to the first surface 12a of the substrate 12. Such a through conductor 21 is commonly referred to as a pin shape.

The through conductor 21 in the sixth embodiment has one such shape, and is attached in the vicinity of the shunt resistor 11 so as not to overlap with the electrode 11B. Since the through conductor 21 has such a shape, its cross-sectional area S is formed to be larger than that of the first embodiment.

To attach the through conductor 21, a plate-shaped conductor portion 211 is inserted into a through hole 22 having a rectangular cross section penetrating the substrate 12, the first energization pattern 13 and the second energization pattern 14, and then soldered. The through hole 22 is formed by applying a copper plating layer 22a to the inner surface of the hole penetrating the substrate 12, the first energization pattern 13 and the second energization pattern 14. Soldering is performed so as to fill the gap between the inner surface of the through hole 22, that is, the inner surface of the copper plating layer 22a and the outer surface of the conductor portion 211 with the solder 23. The configuration other than the through conductor 21 and the through hole 22 is the same as that of the first embodiment.

Since the electronic circuit device 10 according to the sixth embodiment is configured as described above, the same effects as those of (1-1) to (1-3) according to the first embodiment can be obtained, and the following can be obtained. It is also possible to play the effect of.

(6-1) The through conductor 21 is provided with a plate-shaped conductor portion 211, and a protrusion 212 is formed at the end portion on the first energization pattern 13 side thereof, so that the through-conductor 21 is prevented from being lifted or dropped during soldering. It is easy to do.

(6-2) Since the through conductor 21 includes a plate-shaped conductor portion 211 and its cross-sectional area S is larger than that of the first embodiment, in the combination of the first energization pattern 13 and the second energization pattern 14. , The wiring resistance R3 on the electric equivalent circuit and the heat transfer resistance from the shunt resistance 11 to the second energization pattern 14 can be reduced. As a result, the temperature rise of the shunt resistor 11, the first energization pattern 13, and the second energization pattern 14 can be further suppressed.

(7th Embodiment)
Next, the electronic circuit device 10 according to the seventh embodiment will be described with reference to FIG.
The electronic circuit device 10 according to the seventh embodiment is a modification of the structure of the through conductor 21 in the sixth embodiment. The same parts as those in the sixth embodiment are designated by the same reference numerals, and the description thereof will be simplified.

As shown in FIG. 19, the through conductor 21 in the seventh embodiment includes a plate-shaped conductor portion 211 as in the sixth embodiment, and is an end of the conductor portion 211 on the first energization pattern 13 side. The shape of the protrusion 212 protruding in the longitudinal direction of the first energization pattern 13 is different in the vicinity of the portion. As shown in FIG. 19, the projecting portion 212 in this embodiment projects in a substantially triangular shape in the cross section of the projecting portion 212 longitudinally crossing the through hole 22 in the penetrating direction. Such a through conductor 21 is commonly referred to as a pin shape having a retaining structure. Other configurations such as the through conductor 21 and the through hole 22 are the same as those in the sixth embodiment.

Since the electronic circuit device 10 according to the seventh embodiment is configured as described above, the effects of (1-1) to (1-3) according to the first embodiment and (6--) according to the sixth embodiment. In addition to being able to exert the effects on 1) and (6-2), the following effects can also be exerted.

(Modification example)
The description of the embodiment is an example of a form that the electronic circuit device 10 according to the present disclosure can take, and is not limited to the form. In addition to the above-described embodiment, the electronic circuit device 10 according to the present disclosure may be a combination of, for example, the following modifications and at least two modifications that do not contradict each other.

-Although the electronic circuit device 10 in each embodiment is configured symmetrically on both the left and right sides with the shunt resistor 11 interposed therebetween, only one of the left and right sides may be the content of the present disclosure. Further, it is not necessary that the left and right sides are completely symmetrical with respect to the shunt resistor 11. In short, it is desirable that the structure does not impair the gist of the present disclosure. For example, the dimensions of the first energization pattern 13a on the right side and the first energization pattern 13b on the left side may be different. Further, the number, shape, etc. of the left and right through conductors 21 may be different.

-In the second embodiment and the third embodiment, about half of the end surface of the through conductor 21 on the first energization pattern 13 side overlaps with the position of the electrode 11B when viewed from the direction perpendicular to the first surface 12a of the substrate 12. However, it is not limited to about half, and can be more than half or less.

-In the third embodiment, the three split-through conductors 21a are provided so that about half of the end faces overlap with the positions of the electrodes 11B in the same manner, but the overlapping area is different for each split-through conductor 21a. You may do so.

-In the second embodiment and the third embodiment, the penetrating conductor 21 is formed by the three split penetrating conductors 21a, but even if the number of the split penetrating conductors 21a is changed to an arbitrary number of two or more. Good.

The cross-sectional area S of the penetrating conductor 21 can be arbitrarily changed within the range where R4 <R1 / 10 is established.
-In each embodiment, the cross-sectional shape of the through conductor 21 may be another shape. For example, in the first to fourth embodiments, the penetrating conductor 21 or the split penetrating conductor 21a has a columnar shape having a circular cross-sectional shape, but the cross-sectional shape may be an appropriate columnar shape such as an ellipse, a quadrangle, or a triangle.

-In the third embodiment and the fourth embodiment, the three split through conductors 21a all have the same shape, but may be a combination of different shapes.
-In the sixth embodiment and the seventh embodiment, the protrusion 212 may be omitted. FIG. 20 illustrates this. As shown in FIG. 20, the plate-shaped conductor portion 211 has an end portion extending to the outside of the first energization pattern 13 and the second energization pattern 14, and is located near both ends in the longitudinal direction of the energization pattern. The protrusion 212 overhanging is not formed.

-In the sixth embodiment and the seventh embodiment, the protrusion 212 is provided near the end on the first energization pattern 13 side, but the present invention is not limited to this, and the protrusion 212 is near the end on the second energization pattern 14 side. It may be provided in.

-In the sixth embodiment and the seventh embodiment, the conductor portion 211 is not particularly limited to a plate shape. That is, the conductor portion 211 may have a rectangular, square, circular, or other cross-sectional shape parallel to the surface of the substrate 12.

-In each of the above embodiments, it has been applied to a drive circuit for a compressor of an air conditioner or a refrigerator / freezer, but it is not limited to such an application. For example, it can be applied to various applications such as feedback control in household power generators, power tools, and the like.

Although the embodiments of the present disclosure have been described above, it will be understood that various modifications of the forms and details are possible without departing from the purpose and scope of the present disclosure described in the claims. ..

D Current flow direction L1 First wiring L2 Second wiring H (of the first energization pattern 13) Thickness dimension S (through conductor) Cross-sectional area Sa (divided through-conductor) cross-sectional area W (of electrode connection) Width dimension Wp (1st energization pattern) Width dimension 1 Power converter 2 Converter 3 Inverter 4 Motor 5 Switching element 6 Diode 7 Switching leg 8 Current detection circuit 9 Controller 10 Electronic circuit device 11 Shunt resistance 11A Conductor 11B Electrode 12 Substrate 12a 1st surface 12b 2nd surface 13 1st energization pattern 13a (inverter part side) 1st energization pattern 13b (converter part side) 1st energization pattern 14 2nd energization pattern 14a (inverter part side) 2nd energization Pattern 14b (converter part side) 2nd energization pattern 15 1st current detection pattern 16 2nd current detection pattern 17 Electrode connection part 21 Through conductor 21a Divided through conductor 22 Through hole 22a Copper plating layer 23 Solder 31 Electronic component 32 Conductor 33 Through hole 33a Copper plating layer 34 Soldier 41 Via 211 Conductor part 212 Protrusion part

Claims (7)

Substrate (12) and
A shunt resistor (11) with an electrode (11B) and
A first energization pattern (13) provided so as to make surface contact with the electrode (11B) on the surface of the substrate (12) facing the shunt resistor (11).
A second energization pattern (14) provided on the other surface of the substrate (12) and
A conductor (32) for electrically connecting an electronic component (31) mounted on the substrate (12), and a conductor (32).
It has a through conductor (21) provided so as to penetrate the substrate (12).
The conductor (32) is inserted into a through hole (33) provided in the substrate (12) and joined to the first energization pattern (13) and the second energization pattern (14).
The through conductor (21) has the first energization pattern (13) and the first energization pattern (13) on the path of the first energization pattern (13) from the position of the electrode (11B) to the position of the conductor (32). 2 Provided so as to connect with the energization pattern (14)
In the first energization pattern (13), the wiring resistance of the portion from the center of the connection portion with the through conductor (21) to the center of the attachment portion of the conductor (32) is set to R1, and the second energization pattern (13) In 14), the wiring resistance of the portion from the center of the connecting portion with the penetrating conductor (21) to the center of the mounting portion of the conductor (32) is R2, and the wiring resistance of the penetrating conductor (21) is R3. When the wiring resistance from the center of the electrode connection portion (17) with the electrode (11B) to the center of the through conductor (21) in the first energization pattern (13) is R4, R3 and R4 are respectively. An electronic circuit device formed so as to have a value less than R1 × 1/10 and a value less than R2 × 1/10. The electronic circuit device according to claim 1, which is configured to detect a current of 2 A or more. The dimension of the electrode connection portion (17) that is perpendicular to the current direction of the first energization pattern (13) and is along the surface of the substrate (12) is defined as the width dimension W of the electrode connection portion (17).
The dimension of the first energization pattern (13) in the direction perpendicular to the surface of the substrate (12) is defined as the thickness H of the first energization pattern (13).
Further, with respect to the through conductor (21), when the cross-sectional area of the cross section parallel to the surface of the substrate (12) is the cross-sectional area S of the through conductor (21).
S> W × H × 30
The electronic circuit device according to claim 1 or 2, wherein the electronic circuit device is formed so as to satisfy the above. The through conductor (21) is provided so that at least a part of the end face on the first energization pattern (13) side overlaps with the position of the electrode (11B) when viewed from a direction perpendicular to the surface of the substrate (12). The electronic circuit device according to any one of claims 1 to 3. The through conductor (21) is provided so that the entire end face on the side of the first energization pattern (13) overlaps the position of the electrode (11B) when viewed from a direction perpendicular to the surface of the substrate (12). The electronic circuit device according to any one of claims 1 to 3. The through conductor (21) includes a conductor portion (211) inserted into a through hole (22) penetrating the substrate (12), the first energization pattern (13), and the second energization pattern (14). The electronic circuit device according to any one of claims 1 to 3, wherein the conductor portion (211) is soldered to the first energization pattern (13) and the second energization pattern (14). The penetrating conductor (21) has a protrusion (212) for retaining at one of both ends protruding from the first energization pattern (13) or the second energization pattern (14) in the conductor portion (211). The electronic circuit apparatus according to claim 6.

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