JP2017203624A - Electronic circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the accuracy of voltage detection by a resistor in an electronic circuit device.SOLUTION: Provided is an electronic circuit device including a resistor (50) having a first and a second conductive pattern (30, 40), a first electrode (51) and a second electrode (52), with a first connection point (P1) for connecting wirings formed in the first conductive pattern (30) off a center line (CL) linking the middle point (M1) of the first electrode (51) and the middle point (M2) of the second electrode (52), wherein a notch (30a) is formed in the first conductive pattern (30) outward of a virtual line (L1) linking the first connection point (P1) and the middle point (M1) of the first electrode (51).SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electronic circuit device having a resistor for voltage detection.

  In a power converter or the like, an electronic circuit device including a resistor (so-called shunt resistor) may be used to detect a current value (see, for example, Patent Document 1). In the example of Patent Document 1, a current flowing out from the current generation point on the pattern passes through the shunt resistor and flows into the current inflow point, and the voltage value between both electrodes of the shunt resistor is detected. Based on the resistance value of the shunt resistor and the detected voltage value, the current value of the current flowing through the shunt resistor can be detected.

Japanese Patent Application Laid-Open No. 2014-056951

  As a result of research conducted by the present inventors, it has been found that the following phenomenon occurs in the electronic circuit device as described above. That is, in the electronic circuit device, the current flowing out from the current generation point flows toward the resistor (shunt resistor) while greatly spreading on the conductive pattern, passes through the resistor, and then greatly increases on the other conductive pattern. After spreading, it flows into the current inflow point. That is, there are various current paths on the conductive pattern, and the resistance value of each path differs depending on the path length, so that the current value also differs for each path. That is, a current value distribution exists on the conductive pattern.

  In particular, in an electronic circuit device having a shunt resistor for voltage detection, a conductive pattern generally has a predetermined area in consideration of heat dissipation, and the current distribution tends to be large. In general, an electrode of a shunt resistor has a predetermined width. Therefore, when such a current distribution exists, the magnitude of the current flowing varies depending on the position of the electrode. As a result, a voltage distribution is generated inside the resistor (resistor). Such a voltage distribution is not preferable because it leads to a decrease in voltage detection accuracy.

  The present invention has been made paying attention to the above-described problem, and an object of the present invention is to improve the voltage detection accuracy by a resistor in an electronic circuit device having a voltage detection resistor (shunt resistor).

In order to solve the above-mentioned problem, the first aspect is
First and second conductive patterns (30, 40) disposed on an insulating substrate (20);
A resistor having a first electrode (51) having a predetermined width connected to the first conductive pattern (30) and a second electrode (52) having a predetermined width connected to the second conductive pattern (40). 50),
With
The first conductive pattern (30) has a position shifted from a center line (CL) connecting the center point (M1) of the first electrode (51) and the center point (M2) of the second electrode (52). The first connection point (P1) for connecting the wiring is formed on the outer side of the imaginary line (L1) connecting the first connection point (P1) and the center point (M1) of the first electrode (51). A notch (30a) is formed in the surface.

  In this configuration, since the notch (30a) is provided, the current cannot be greatly spread outside the virtual line (L1). Therefore, the voltage distribution width in the first electrode (51) and the second electrode (52) of the resistor (50) is reduced.

The second aspect is the first aspect,
The second conductive pattern (40) has an extension (40b) extending toward the notch (30a).

  In this configuration, the heat generated by the resistor (50) and the like can be radiated by the extension (40b).

Further, the third aspect is the first or second aspect,
The first conductive pattern (30) is provided with a plurality of first connection points (P1-1, 2, 3),
The notch (30a) is formed outside the virtual line (L1) defined for the first connection point (P1-1) located farthest from the center line (CL). And

  With this configuration, the voltage distribution width in the resistor (50) is reduced in the electronic circuit device in which the connection points (P1-1, 2, 3) of the wiring are provided at a plurality of locations.

The fourth aspect is any one of the first to third aspects.
In the second conductive pattern (40), a second connection point (P2) for connecting a wiring is formed at a position shifted from the center line (CL). The second connection point (P2) and the second electrode A notch (40a) is formed outside an imaginary line (L2) connecting the center point (M2) of (52).

  With this configuration, in the second conductive pattern (40), as in the first conductive pattern (30), the current cannot be greatly spread outside the virtual line (L2) due to the notch (40a). Therefore, the voltage distribution width in the first electrode (51) and the second electrode (52) of the resistor (50) is further reduced.

Moreover, a 5th aspect is a 4th aspect.
The first conductive pattern (30) has an extension (30b) extending toward the notch (40a) side of the second conductive pattern (40).

  In this configuration, the extension (30b) in the first conductive pattern (30) can dissipate heat generated by the resistor (50) and the like.

  According to the first aspect, in the electronic circuit device having the voltage detection resistor, it is possible to improve the voltage detection accuracy by the resistor.

  Moreover, according to the 2nd aspect, it becomes possible to aim at the improvement of heat dissipation.

  Moreover, according to the 3rd aspect, in the electronic circuit device provided with the connection point of wiring in several places, it becomes possible to aim at the improvement of the voltage detection precision by a resistor.

  According to the fourth aspect, in the electronic circuit device having the voltage detection resistor, it is possible to improve the voltage detection accuracy by the resistor more reliably.

  Moreover, according to the 5th aspect, it becomes possible to improve heat dissipation more reliably.

FIG. 1 illustrates a configuration example of a power converter including an electronic circuit device according to the first embodiment. FIG. 2 shows a configuration example of the electronic circuit device. FIG. 3 is an enlarged view of the vicinity of the resistor in the electronic circuit device. FIG. 4 schematically shows a current path in the conventional example. FIG. 5 shows a voltage distribution curve in the electronic circuit device of the first embodiment and a voltage distribution curve in the conventional electronic circuit device. FIG. 6 schematically shows a current path in the electronic circuit device of the first embodiment. FIG. 7 shows the relationship between the notch size and the detected voltage error. FIG. 8 shows the definition of the notch dimension in the simulation of the detection voltage error. FIG. 9 is a plan view of the electronic circuit device according to the second embodiment. FIG. 10 is a plan view of an electronic circuit device according to a modification of the second embodiment. FIG. 11 is a plan view of the electronic circuit device according to the third embodiment. FIG. 12 is a plan view of an electronic circuit device according to a modification of the third embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

Embodiment 1 of the Invention
FIG. 1 shows a configuration example of a power converter (1) including an electronic circuit device (10) according to Embodiment 1 of the present invention. In addition to the electronic circuit device (10), the power converter (1) includes a converter (2), an electrolytic capacitor (3), an inverter (4), a current detection circuit (5), and a controller (6). . The power converter (1) is connected to the motor (M). For example, the motor (M) is constituted by an embedded magnet synchronous motor (IPM) and is used to drive a compressor (not shown) of an air conditioner.

  The converter (2) rectifies an input AC voltage from an AC power source (not shown). The electrolytic capacitor (3) is connected between the first and second wirings (W1, W2) connecting the converter (2) and the inverter (4), and smoothes the output of the converter (2). The inverter (4) converts the DC voltage generated by the electrolytic capacitor (3) into an output AC voltage (in this example, a three-phase AC voltage) and supplies it to the motor (M). In this example, the inverter (4) has six switching elements (Su, Sv, Sw, Sx, Sy, Sz) and six freewheeling diodes (Du, Dv, Dw, Dx, Dy, Dz). ing. Each connection point of switching element (Su, Sv, Sw) and switching element (Sx, Sy, Sz) is connected to each phase coil (u-phase, v-phase, w-phase coil) of motor (M). Has been. The free-wheeling diodes (Du, Dv, Dw, Dx, Dy, Dz) are respectively connected in antiparallel to the switching elements (Su, Sv, Sw, Sx, Sy, Sz).

  The electronic circuit device (10) includes a resistor (50) serving as a shunt resistor. The electronic circuit device (10) is provided on the wiring in the power converter (1) (in this example, the first wiring (W1)). The configuration of the electronic circuit device (10) will be described in detail later.

  The current detection circuit (5) detects the current value of the current flowing through the resistor (50) based on the voltage value between both electrodes of the resistor (50) and the resistance value of the resistor (50). The current value of the current flowing through the resistor (50) corresponds to the current value of the current flowing through the motor (M). Based on the current value detected by the current detection circuit (5) (that is, the current value of the current flowing through the motor (M)), the controller (6) switches the switching elements (Su, Sv, Sw, A gate signal (G) is supplied to Sx, Sy, Sz to control the switching operation of the switching elements (Su, Sv, Sw, Sx, Sy, Sz).

<Details of electronic circuit device>
FIG. 2 shows a configuration example of the electronic circuit device (10). FIG. 2 is a plan view of the electronic circuit device (10). As shown in FIG. 2, the electronic circuit device (10) includes an insulating substrate (20), a first conductive pattern (30), a second conductive pattern (40), and a resistor (50). FIG. 3 is an enlarged view of the vicinity of the resistor (50) in the electronic circuit device (10). As shown in FIG. 3, the resistor (50) is provided with a first lead wire (60) and a second lead wire (70).

-Resistor-
The resistor (50) includes a first electrode (51), a second electrode (52), and a resistor (53). In this example, the resistor (53) has a rectangular plate shape in plan view, and the first electrode (51) is formed along one of the two sides (long sides) in the longitudinal direction of the resistor (53). The second electrode (52) is formed along the other long side. In this example, the first electrode (51) and the second electrode (52) are formed over the entire length of the long side of the resistor (53), and the plan view of these electrodes (51, 52) is: It is assumed that the resistor (53) is a rectangle having a long side in the longitudinal direction.

-Insulating substrate, conductive pattern-
The insulating substrate (20) is made of a flat insulating material (for example, glass epoxy resin). The first conductive pattern (30) and the second conductive pattern (40) are made of a conductive material (eg, copper, copper alloy, aluminum, aluminum alloy, etc.) formed into a thin film, and are insulated at a predetermined interval. It is provided on one surface of the substrate (20). In this example, the first conductive pattern (30) corresponds to the wiring portion between the resistor (50) and the inverter (4) in the first wiring (W1) shown in FIG. The pattern (40) corresponds to the wiring portion between the converter (2) and the resistor (50) in the first wiring (W1) shown in FIG.

  In this example, as shown in FIG. 2, the first and second conductive patterns (30, 40) have a shape in which one corner of a rectangle is cut out in a triangular shape in plan view. The first conductive pattern (30) and the second conductive pattern (40) are arranged such that one side (31, 41) is parallel to each other. The distance (D0) between these sides (31, 41) is set smaller than the length of the resistor (53) in the short direction.

  As shown in FIG. 3, the resistor (50) is attached so as to straddle the first conductive pattern (30) and the second conductive pattern (40). Specifically, in the resistor (53), the first electrode (51) is connected to the edge (E1) of the side (31) by solder or the like, and the second electrode (52) is connected to the edge (E2) of the side (41). ) Are connected by soldering. The long side of the first electrode (51) is substantially parallel to the side (31), and the long side of the second electrode (52) is substantially parallel to the side (41).

  Further, as shown in FIG. 2, the first conductive pattern (30) is provided with a first connection point (P1) for connecting the wiring, and the second conductive pattern (40) is also connected to the second conductive pattern (40). A connection point (P2) is formed. In this example, the first connection point (P1) is a location (current generation location) where current flows from the outside of the electronic circuit device (10), and the second connection point (P2) is from the resistor (50). This is where the current flows and also where the current flows out of the electronic circuit device (10) (see FIG. 2).

  Here, a virtual line (hereinafter referred to as a center line (CL)) connecting the center point (M1) of the first electrode (51) and the center point (M2) of the second electrode (52) is defined. The center point (M1) of the first electrode (51) is the midpoint of the long side of the first electrode (51), and the long side here is the two long sides of the first electrode (51). This is the outer side of the resistor (53) (see FIG. 3). Similarly, the center point (M2) of the second electrode (52) is the midpoint of the long side of the second electrode (52). Here, the center point (M2) is defined by paying attention to the outer side of the resistor (53) among the two long sides of the second electrode (52).

  As shown in FIG. 2, when the first connection point (P1) is viewed on the basis of the center line (CL), the first connection point (P1) is closer to the first conductive pattern (30 than the center line (CL). ) (In FIG. 2, it is provided at a position close to the lower end of the center line (CL)). That is, the first connection point (P1) is at a position shifted from the center line (CL). Similarly, the second connection point (P2) is also provided at a position shifted from the center line (CL). Specifically, the second connection point (P2) is closer to the end of the second conductive pattern (40) than the center line (CL) (in FIG. 2, the end above the center line (CL)). Close position.

  As described above, the first and second conductive patterns (30, 40) have a shape in which one corner of a rectangle is cut out. Specifically, the notch (30a) of the first conductive pattern (30) is more than the virtual line (L1) connecting the first connection point (P1) and the center point (M1) of the first electrode (51). It is formed on the outside. Here, “outside the imaginary line (L1)” is the side farther from the imaginary line (L1) in the direction from the center line (CL) to the first connection point (P1). As seen in FIG. 2, the notch (30a) is provided below the imaginary line (L1). In particular, in this electronic circuit device (10), the first connection point (P1) and the first electrode The first conductive pattern (30) does not exist slightly outside the imaginary line (the shortest imaginary line (L3)) that connects (51) with the shortest distance. In the first conductive pattern (30), no notch is provided on the inner side of the virtual line (L1).

  Similarly, the notch (40a) of the second conductive pattern (40) is outside the imaginary line (L2) connecting the second connection point (P2) and the center point (M2) of the second electrode (52). Is formed. In this case, “outside the imaginary line (L2)” is the side farther from the imaginary line (L2) in the direction from the center line (CL) to the second connection point (P2). When this is seen in FIG. 2, the notch (40a) is provided above the virtual line (L2). In particular, in this electronic circuit device (10), the notch (2) of the second conductive pattern (40) In 40a), the second conductive pattern (40) does not exist slightly outside the imaginary line (shortest imaginary line (L4)) that connects the second connection point (P2) and the second electrode (52) at the shortest. In the second conductive pattern (40), no notch is provided inside the virtual line (L2).

-Action of notches-
FIG. 4 schematically shows a current path in an electronic circuit device (hereinafter referred to as a conventional example) in which a conductive pattern is not cut. In FIG. 4, the current path is indicated by a broken line. In the conventional example, the current generated at the current generation location (P100) flows toward the shunt resistor (500) on the conductive pattern (300) provided with the current generation location (P100). At this time, as shown in FIG. 4, a plurality of current paths are formed on the conductive pattern (300). In the conventional example, the current flowing through these current paths is finally shunt resistance ( 500) electrode (501).

  Some of these current paths greatly extend on the conductive pattern (300). Among these current paths, there is also the shortest current path (shortest path) that connects the end point (A) of the electrode (501) of the shunt resistor (500) and the current generation location (P100) with a straight line. The shortest path has the smallest resistance value among these current paths. Therefore, in the conventional example, the current value is the largest in this shortest path. That is, in the conventional electrode (501), the magnitude of the current flowing at each point between the end point (A) and the end point (B) is different. Generally, since the shunt resistor (500) has a resistor (502) having a uniform resistance value, if the current value varies depending on the position of the electrode (501), the voltage distribution in the electrode (501) is reduced. Will occur. That is, in the shunt resistor (500), the detected voltage differs depending on the position of the electrode (501).

  In FIG. 5, the relationship between the position on the electrode (501) and the detected voltage (hereinafter referred to as a voltage distribution curve) in a conventional resistor is shown by a broken line. The positions (A) and (B) in FIG. 5 correspond to the end points (A) and (B) of the electrode (501), respectively, and the positions (M1, M2) are the center points (M1) of the electrode (501). ). As shown in FIG. 5, in the electrode (501), the voltage detected at both ends (A, B) is the highest, and at the center point (M1, M2) (midpoint of position (A) and position (B)) The detected voltage is the lowest. In this example, the voltage distribution curve is symmetrical.

  FIG. 6 schematically shows a current path in the electronic circuit device (10) of the present embodiment. Also in FIG. 6, the current path is indicated by a broken line. As shown in FIG. 6, a plurality of current paths are formed on the first and second conductive patterns (30, 40). FIG. 5 shows a voltage distribution curve in the resistor (50) with a solid line. Regarding the voltage distribution curve of the resistor (50), the position (A) and the position (B) in FIG. 5 correspond to the end point (A) and the end point (B) of the first electrode (51), respectively, and the position (M1 , M2) corresponds to the center point (M1) (or center point (M2)) of the first electrode (51). Also in the resistor (50), the voltage detected at both ends (A, B) is the highest, and the voltage detected at the center point (M1, M2) is the lowest. The voltage distribution curve is also symmetrical in the resistor (50).

  In the first conductive pattern (30) of the present embodiment, the notch (30a) is formed outside the imaginary line (L1). Therefore, as shown in FIG. 6, it is located outside the imaginary line (L1). The current cannot spread greatly. Therefore, in this embodiment, the path of the current flowing into the end point (A) of the first electrode (51) is shorter than that in the conventional example. That is, in this embodiment, the resistance value of the current path from the first connection point (P1) to the end point (A) of the first electrode (51) decreases, and as a result, the detection voltage at the end point (A) decreases. become.

  Conventionally, the current that has flown outside the virtual line (L1) and has flown into the end point (A) flows into a point on the first electrode (51) that is closer to the end point (B). Thereby, in the present embodiment, the detection voltage at the current detection position (generally the center of the electrode) is increased. That is, the voltage distribution width (detected voltage error (ΔV)) at the electrodes (51, 52) of the resistor (50) is reduced (see the solid line in FIG. 5). The detected voltage error (ΔV) is a voltage distribution width at the electrodes (51, 52) of the resistor (50), and more specifically, a difference between the maximum voltage and the minimum voltage of the voltage distribution. Similarly, in the second conductive pattern (40), the current flowing into the second connection point (P2) after spreading from the end point (A) decreases, and from this point, the voltage distribution width ( Detection voltage error (ΔV)) is reduced.

−Size of cutout−
FIG. 7 shows the relationship between the size of the notch and the detected voltage error (ΔV). In FIG. 7, the detection voltage error (ΔV) is obtained by simulation for a plurality of notch ratios, and the ratio to the detection voltage error (ΔV) when there is no notch is plotted as an improvement rate (%). Here, the notch ratio (%) means the distance from the end of the first conductive pattern (30) to the end of the resistor (50) in the first conductive pattern (30) as shown in FIG. The ratio (Y / X) between (X) and the distance (Y) from the end of the first conductive pattern (30) to the starting point of the notch (30a) on the side (31). In this example, X = 20.1 mm (fixed value). Of course, this value is exemplary. In this simulation, the starting point of the notch (30a) on the side (32) is a fixed value. As this fixed value, for example, it is possible to consider the maximum possible value in consideration of the positions of the first connection point (P1) and the second connection point (P2). In this example, the fixed value is 20 mm. Of course, this value is exemplary. The definition of the notch ratio (%) in the second conductive pattern (40) is the same as the definition in the first conductive pattern (30) (see FIG. 8).

  When changing the notch ratio (%) in the simulation, the distance (Y) is changed. That is, when Y = 0, the notch ratio = 0%, which corresponds to a conductive pattern having no notch. Further, when Y = X, the notch ratio = 100%. The example of FIG. 2 (this embodiment) corresponds to a shape with a notch ratio = 100%, and the example of FIG. 4 corresponds to a notch ratio = 0% (that is, a conventional example).

  The simulation result shown in FIG. 7 is an example in which both the cutout (30a) of the first conductive pattern (30) and the cutout (40a) of the second conductive pattern (40) are formed at the same cutout ratio. When the notch ratio is 80% or more, an improvement effect appears.

<Effect in this embodiment>
As described above, according to this embodiment, in the electronic circuit device having the voltage detection resistor (shunt resistor), it is possible to improve the voltage detection accuracy by the resistor.

<< Embodiment 2 of the Invention >>
FIG. 9 is a plan view of the electronic circuit device (10) according to the second embodiment. In this example, the shapes of the first conductive pattern (30) and the second conductive pattern (40) of the first embodiment are changed. Specifically, in the present embodiment, the first conductive pattern (30) has an extension (30b) extending toward the notch (40a) side of the second conductive pattern (40), and the second conductive pattern (30) 40) has an extension part (40b) extending toward the notch (30a) side of the first conductive pattern (30). In this example, each extension part (30b, 40b) is triangular according to the shape of the notch (30a, 40a) which has opposed. In FIG. 9, the extension part (30b) and the extension part (40b) are hatched. The extension (30b) and the extension (40b) can dissipate heat generated by the resistor (50) and the like. That is, in the present embodiment, the area of the first and second conductive patterns (30, 40) is increased compared to the first embodiment, so that the heat dissipation effect can be enhanced.

  On the other hand, even if the extension (30b) and the extension (40b) are provided, the detection voltage error (ΔV) does not increase. In this example, the extension part (30b) is located outside the end point (B) of the first electrode (51), and the current flowing from the first connection point (P1) toward the first electrode (51) A path is not formed in this part. Therefore, even if the extension part (30b) is provided, the detection voltage error (ΔV) does not increase compared to the first embodiment. Note that “outside the end point (B) of the first electrode (51)” means that the center line (CL) is closer to the end point (B) of the first electrode (51) than the end point (B). The side that goes away.

  Similarly, the extension (40b) is located outside the end point (B) of the second electrode (52), and the current path of the current from the second electrode (52) to the second connection point (P2) Is not formed. Therefore, also in this respect, even if the extension portion (40b) is provided, the detection voltage error (ΔV) does not increase as compared with the first embodiment. Note that “outside the end point (B) of the second electrode (52)” means that the center line (CL) is closer to the end point (B) of the second electrode (52) than the end point (B). The side that goes away.

  In addition, the shape of each extension part (30b, 40b) is an illustration, and does not need to be triangular. Moreover, you may make it provide an extension part only in one side of a 1st and 2nd conductive pattern (30,40).

<< Modification of Embodiment 2 >>
FIG. 10 is a plan view of an electronic circuit device (10) according to a modification of the second embodiment. In this example, the first conductive pattern (30) in the electronic circuit device (10) of the second embodiment is modified. Specifically, the first conductive pattern (30) of the present modification is provided with a plurality (three in this example) of first connection points (P1). This is one of the configurations adopted when the current value of each phase is detected by one resistor (50) when the inverter (4) outputs a three-phase alternating current. In FIG. 10, in order to identify each first connection point (P1), a branch number is added to the end of the reference symbol (for example, P1-1, P1-2, etc.).

  When there are a plurality of first connection points (P1) in this way, the notch (30a) of the first conductive pattern (30) is the first connection point located farthest from the center line (CL). It may be formed outside the virtual line (L1) defined for (P1). In the example of FIG. 10, the first connection point (P1-1) is located farthest from the center line (CL), and the notch (30a) is defined for the first connection point (P1-1). It is formed outside the virtual line (L1) (lower than the virtual line (L1) in the example of FIG. 10). As a result, the potential distribution in the first electrode (51) can be further reduced. Therefore, it is possible to obtain the same effect as that of the above embodiment also in this modification.

<< Embodiment 3 of the Invention >>
FIG. 11 is a plan view of an electronic circuit device (10) according to Embodiment 3 of the present invention. This example also improves the heat dissipation of the first and second conductive patterns (30, 40). Specifically, in the present embodiment, as shown in FIG. 11, the first conductive pattern (30) has a depth that does not reach the side (31), starting from the side (32) connected to the side (31). A notch (30a) is formed by a cut parallel to the imaginary line (L1). This notch (30a) is also located on the side (outside) away from the virtual line (L1) in the direction from the center line (CL) to the first connection point (P1), as in the other embodiments. ing. Further, in this example, by adjusting the width of the notch (30a), a part of the first conductive pattern (30) is left outside the notch (30a) (hereinafter, the remaining portion (30c )). Looking at this in FIG. 11, the notch (30a) is below the imaginary line (L1). In this example, there is a triangular remaining portion (30c).

  Similarly, the second conductive pattern (40) also has a depth that does not reach the side (41) from the side (42) connected to the side (41) and is parallel to the imaginary line (L2). A notch (40a) is formed. This notch (40a) is also formed on the side (outside) away from the virtual line (L2) in the direction from the center line (CL) toward the second connection point (P2). Also, in the second conductive pattern (40), a part of the second conductive pattern (40) is left outside the notch (40a) by adjusting the width of the notch (40a) (hereinafter referred to as “the second conductive pattern (40a)”). , Called the remaining part (40c)). Looking at this in FIG. 11, the notch (40a) is above the imaginary line (L2). In this example, there is a triangular remaining portion (40c).

  As described above, in this embodiment, by providing the remaining portion (30c) and the remaining portion (40c), the heat radiation area of the first and second conductive patterns (30, 40) is increased as compared with the first embodiment. It becomes possible. Further, in the first conductive pattern (30), the current that wraps around the imaginary line (L1) (below the imaginary line (L1) in FIG. 11) is very small, and the second conductive pattern (40) The current that wraps around the outside of the imaginary line (L2) (in FIG. 11, above the imaginary line (L2)) is very small. Therefore, also in this embodiment, it is possible to improve the voltage detection accuracy by the resistor while improving the heat dissipation of the resistor.

<< Modification of Embodiment 3 >>
FIG. 12 is a plan view of an electronic circuit device (10) according to a modification of the third embodiment. In this example, the shape of the notches (30a, 40a) is different from that of the third embodiment. Specifically, in this example, the first conductive pattern (30) forms a triangular cutout (30a) at a depth that does not reach the side (31) from the side (32) continuous to the side (31). doing. As a result, in this example, the remaining portion (30c) of the first conductive pattern (30) is substantially rectangular. Similarly, a triangular cutout (40a) is formed in the second conductive pattern (40), and the remaining portion (40c) of the second conductive pattern (40) is also substantially rectangular.

  Even in this modification, it is possible to increase the heat radiation area as compared with the first embodiment. Also in this example, in the first conductive pattern (30), there is very little current flowing outside the imaginary line (L1) (lower side than the imaginary line (L1) in FIG. 12), and the second conductive pattern (30). Even at (40), the current that wraps around the outside of the virtual line (L2) (in FIG. 12, above the virtual line (L2)) is very small. Therefore, also in this modification, it is possible to improve the voltage detection accuracy by the resistor while improving the heat dissipation of the resistor.

  In the third embodiment and the modified example of the third embodiment, the heat dissipation effect can be improved even if only one of the remaining portion (30c) and the remaining portion (40c) is provided. Further, the shape of the remaining portion (30c, 40c) is an example, and is not limited to the shape shown in FIG. 11 or FIG.

<< Other Embodiments >>
The voltage detection accuracy can be improved even if the notch is formed only in one of the two conductive patterns (30, 40).

  Moreover, the shape of the notch is an exemplification, and is not limited to the shape shown in the embodiment or the modification. For example, in the example of FIG. 2, there are some first conductive patterns (30) outside the shortest virtual line (L3), but inside the shortest virtual line (L3) (in FIG. 2, the shortest virtual line (L3) It is also possible to configure the notch (30a) of the first conductive pattern (30) to enter the upper part (above L3). Similarly, the notch (40a) of the second conductive pattern (40) can be configured to enter the inside of the shortest imaginary line (L4) (below the shortest imaginary line (L4) in FIG. 2).

  The present invention is useful as an electronic circuit device having a resistor for voltage detection.

DESCRIPTION OF SYMBOLS 10 Electronic circuit apparatus 20 Insulating substrate 30 1st conductive pattern 30b Extension part 40 2nd conductive pattern 40b Extension part 50 Resistor 51 1st electrode 52 2nd electrode L1 Virtual line L2 Virtual line M1 Center point M2 Center point P1 1st connection Point P2 Second connection point

Claims (5)

First and second conductive patterns (30, 40) disposed on an insulating substrate (20);
A resistor having a first electrode (51) having a predetermined width connected to the first conductive pattern (30) and a second electrode (52) having a predetermined width connected to the second conductive pattern (40). 50),
With
The first conductive pattern (30) has a position shifted from a center line (CL) connecting the center point (M1) of the first electrode (51) and the center point (M2) of the second electrode (52). The first connection point (P1) for connecting the wiring is formed on the outer side of the imaginary line (L1) connecting the first connection point (P1) and the center point (M1) of the first electrode (51). A notch (30a) is formed in the electronic circuit device. In claim 1,
The electronic circuit device, wherein the second conductive pattern (40) has an extension (40b) extending toward the notch (30a). In claim 1 or claim 2,
The first conductive pattern (30) is provided with a plurality of first connection points (P1-1, 2, 3),
The notch (30a) is formed outside the virtual line (L1) defined for the first connection point (P1-1) located farthest from the center line (CL). An electronic circuit device. In any one of Claims 1-3,
In the second conductive pattern (40), a second connection point (P2) for connecting a wiring is formed at a position shifted from the center line (CL). The second connection point (P2) and the second electrode An electronic circuit device, wherein a notch (40a) is formed outside a virtual line (L2) connecting the center point (M2) of (52). In claim 4,
The electronic circuit device, wherein the first conductive pattern (30) has an extension (30b) extending toward the notch (40a) side of the second conductive pattern (40).

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