JP2008042052A - Circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve heat dissipation effects without affecting the operation in a circuit board. <P>SOLUTION: In this circuit board 10, where a plurality of circuit configuring components 30 are mounted on each component-mounting part 23, formed on any of a plurality of conductor patterns 22 formed on a printed board 20, one or more heat dissipating components 40 for which can be loaded by using a component-loading device are mounted at a section other than the component-mounting section of predetermined conductor patterns 22b and 22c of the conductor patterns 22 so as to be housed inside the range of the conductor patterns. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a circuit board in which a plurality of circuit components are mounted on each component mounting portion formed in any of a plurality of conductor patterns formed on a printed board.

  As this type of circuit board, the one shown in Patent Document 1 is known. In this circuit board, as shown in FIG. 4 of Patent Document 1, a resistor Ra is connected between the copper foil pattern 5 and the copper foil pattern 11 to which the collector of the transistor Tr having a large heat generation amount is connected. The resistor Ra is used as a heat dissipation path to dissipate heat to the ground line 9 to which the copper foil pattern 11 is connected. At this time, the impedance of the resistor Ra is made sufficiently large so that the power consumption is reduced.

According to this, by connecting a circuit component to the heat generating part of the heat generating component and using this circuit component as a heat dissipation path, it can be mounted at the same time as a normal mounting component. There is no need for a separate production process as in the case of providing simple parts. Therefore, the cost for such an electronic circuit device can be suppressed. Further, a larger heat dissipation effect can be obtained by making the heat radiation destination larger in terms of area and by using a ground line or a power supply line soldered to a casing covering the electronic circuit device.
JP 2001-68877 A

  In the circuit board described in Patent Document 1 described above, circuit components are used as a heat radiation path to a ground line or a power supply line as a heat radiation destination. However, since the circuit component is small, it becomes a rate limiting part for heat conduction, and there is a possibility that sufficient heat conduction may not be performed. In addition, when the circuit design is made on the assumption that the resistor Ra has a sufficiently large impedance, the operation of the circuit device may be affected if the resistor Ra fails.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to improve a heat dissipation effect in a circuit board without affecting the operation of the circuit board.

  In order to solve the above-mentioned problem, the structural feature of the invention according to claim 1 is that a plurality of circuit components are provided in each component mounting portion formed in any one of the plurality of conductor patterns formed on the printed circuit board. In the mounted circuit board, one or a plurality of heat dissipating components that can be mounted using the component mounting device are within the range of the conductor pattern in a portion of the conductor pattern other than the component mounting portion of the predetermined conductor pattern. It was implemented to fit.

  The structural feature of the invention according to claim 2 is that, in claim 1, the heat dissipation component is a ceramic chip component.

  The structural feature of the invention according to claim 3 is that, in claim 1, the heat dissipating part is a chip part using a metal material for the structure.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the predetermined conductor pattern is a conductor electrically connected to a component mounting portion on which a heat generating component is mounted. It is a pattern.

  The structural feature of the invention according to claim 5 is that, in claim 4, the predetermined conductor pattern is formed on the back surface of the surface on which the heat generating component is mounted.

  The structural feature of the invention according to claim 6 is that in any one of claims 1 to 5, the predetermined conductor pattern constitutes a circuit on a printed circuit board.

  The structural feature of the invention according to claim 7 is that, in the case where there are a plurality of types of circuit components in any one of claims 1 to 6, an appropriate one is selected as a component for heat dissipation. Is to implement it.

  In the invention according to claim 1 configured as described above, since one or a plurality of heat dissipating parts are mounted on a predetermined conductor pattern, the heat conducting path to the atmosphere on the conductor pattern by the heat dissipating parts. That is, the heat radiation path (heat radiation area) can be increased. Thereby, the heat dissipation effect can be improved. Further, the volume of the heat conduction path through which heat is conducted along the conductor pattern is increased by the amount of the heat dissipating component, so that the temperature is hardly increased. Furthermore, when a current flows along the conductor pattern, the volume (cross-sectional area) of the portion through which the current flows in the conductor pattern and the heat dissipating component increases, so the amount of heat generated by energization can be reduced.

  When chip resistors and chip capacitors are used as heat dissipation components, since the heat dissipation components are mounted so as to be within the range of one conductor pattern, the chip resistors and chip capacitors are connected between the same potential. Even if the heat radiation component is provided on the conductor pattern, the operation of the circuit board is not affected at all. Further, even if the heat dissipating component breaks down, it does not affect the operation of the circuit board. Therefore, in the circuit board, the heat radiation effect can be improved without affecting the operation of the circuit board.

  Further, since the heat dissipating component is mounted on the printed board by the component mounting apparatus, the heat dissipating component can be easily and surely mounted without any trouble and without any special process.

  In the invention according to claim 2 configured as described above, in the invention according to claim 1, since the heat dissipation component is a ceramic chip component, a relatively expensive heat dissipation component such as a heat sink is not used. Sufficient heat dissipation effect can be obtained by using inexpensive parts.

  In the invention according to claim 3 configured as described above, in claim 1, since the heat dissipating component is a chip component (for example, a chip capacitor) using a metal material for the structure, In addition to the functions and effects of the invention, the heat dissipation can be further improved.

  In the invention according to claim 4 configured as described above, in the invention according to any one of claims 1 to 3, the predetermined conductor pattern is electrically connected to a component mounting portion on which a heat-generating component is mounted. Therefore, the heat of the heat generating component can be reliably and promptly radiated by the heat radiating component provided in the predetermined conductor pattern.

  In the invention according to claim 5 configured as described above, in the invention according to claim 4, the predetermined conductor pattern is mounted because it is formed on the back surface of the surface on which the heat generating component is mounted. By using not only the surface but also the back surface, heat can be radiated more efficiently. That is, space saving and high heat dissipation effect can be obtained.

  In the invention according to claim 6 configured as described above, in the invention according to any one of claims 1 to 5, the predetermined conductor pattern is formed only for the purpose of mounting the heat dissipating component. Since a circuit on a printed circuit board is used instead of a dedicated conductor pattern, an efficient heat radiation effect can be obtained by using the conductor pattern constituting the circuit as it is and by making a small change (for example, changing a resist screen mask). be able to.

  In the invention according to claim 7 configured as described above, in the invention according to any one of claims 1 to 6, when there are a plurality of types of circuit components, it is suitable as a component for heat dissipation. Since it is selected and mounted, circuit components originally mounted on a printed circuit board can be used without using relatively expensive heat-dissipating components such as a heat sink. Heat dissipation effect can be obtained. Further, when a circuit board is manufactured using a component mounting apparatus (for example, a chip mounter), it is not necessary to use an extra parts cassette, so that labor is not required in the preparation process. Therefore, cost reduction and man-hour reduction can be achieved.

1) First Embodiment Hereinafter, a first embodiment of a circuit board according to the present invention will be described with reference to the drawings. In the first embodiment, a case where the heat generating component is an IC will be described as an example. FIG. 1A is a top view showing an upper surface (surface on which an IC is mounted) of the circuit board 10 on which the circuit component 30 and the heat dissipation component 40 are mounted on the printed circuit board 20, and FIG. FIG. 3 is a bottom view showing a lower surface of the circuit board 10. FIG. 2A is a top view showing the top surface of the printed circuit board 20, and FIG. 2B is a bottom view showing the bottom surface of the printed circuit board 20. FIG. 3 is a cross-sectional view of the circuit board.

  The circuit board 10 is obtained by mounting a circuit component 30 on a printed board 20. The printed circuit board 20 is formed of a base material 21 formed of an insulating member (for example, a glass base material epoxy resin, a paper base material phenol resin, etc.) and a conductive member (for example, copper foil) on the surface of the base material 21. It is composed of a plurality of conductor patterns 22. The printed circuit board 20 is covered with an insulating thin film 50 (for example, a solder resist) except for parts such as the component mounting portion 23, the through hole 24, and a test pad (not shown) that do not require coating. A plurality of circuit components 30 are mounted on each component mounting portion 23 of the printed circuit board 20. The mounting means that the circuit component 30 is attached to the component attachment portion 23 of the conductor pattern 20 of the printed circuit board 20 by soldering.

  The conductor pattern 22 has a part mounting portion 23 on which a circuit component 30 is mounted on a part of the conductor pattern 22, and a through hole 24 for connecting to the back conductor pattern on a part of the conductor pattern 22. Some are formed, some are not formed with the component mounting portion 23, and some are not formed with the through hole 24.

  In the present embodiment, as shown in FIG. 2, there are conductor patterns 22 a to 22 e as the conductor pattern 22. The conductor pattern 22a is a conductor pattern in which a component mounting portion 23a to which each lead 31a of the IC 31 is soldered is formed at one end. At the other end of the conductor pattern 22a, a through hole 24a is formed, or another component mounting portion is formed.

  The conductor pattern 22b is a conductor pattern having a component mounting portion 23b formed in a rectangular shape to which the metal plate 31b of the IC 31 is soldered. The conductor pattern 22b has an extended portion 22b1 extending from a corner portion of the component mounting portion 23b. The extension 22b1 is connected to the ground line and has a heat dissipation function.

  The conductor pattern 22b is connected to a conductor pattern 22c formed on the back surface through a plurality of through holes 24b. The conductor pattern 22c is formed wide and has a heat dissipation function and also functions as a ground line. The extended portion 22b1 and the conductor pattern 22c are wider than the heat dissipation component 40.

  The conductor pattern 22d is a conductor pattern in which a component mounting portion 23d to which each electrode 32b of the resistor 32 is soldered is formed at one end. A through hole is formed at the other end of the conductor pattern 22d, or a component mounting portion for other components is formed.

  The conductor pattern 22e is a conductor pattern in which a component mounting portion 23e to which each electrode 33b of the capacitor 33 is soldered is formed at one end. A through hole is formed at the other end of the conductor pattern 22e, or a component mounting portion for other components is formed.

  Examples of the circuit component 30 include an IC (integrated circuit) 31, a resistor 32, a capacitor 33, a diode (not shown), and a transistor. FIG. 1 shows an IC 31, a resistor 32, a capacitor 33, and a heat radiating component 40 among the circuit component 30 mounted. The circuit component 30 refers to a component that exhibits an electrical function in configuring (forming) an electronic circuit, and has a different use from the heat dissipation component 40 mainly having a heat dissipation function described later. It is.

  The IC 31 performs processing such as inputting a signal from various sensors (for example, a wheel speed sensor that is provided in the vehicle and detects the speed of the wheel) and generates a reference voltage. Because it is large, it generates heat. The IC 31 is a heat generating component. The IC 31 is a QFP (quad flat package) type IC and is formed in a square shape. A plurality of leads 31a (terminals) protrude from the four sides. A metal plate 31b for heat dissipation is provided on the bottom surface.

  The resistor 32 is a so-called chip resistor (chip component) and has a structure as shown in FIG. The resistor 32 includes a main body 32a formed in a rectangular parallelepiped using ceramics as a support, a pair of U-shaped electrodes 32b and 32b closely attached so as to cover both ends of the main body 32a, and a pair of electrodes 32b and 32b. And a resistor (resistive film) 32c that is disposed on the surface of the main body 32a and connects the electrodes 32b and 32b. The main body 32a is covered with an insulating member. The resistor (resistance film) 32c is formed of a metal material, and the resistance value is set according to the shape and size of the resistor (resistance film) 32c. Note that the metal material of the resistor 32c generally has better thermal conductivity than ceramics. The size is 1.0 × 0.5 × 0.4 (mm), 1.6 × 0.8 × 0.5 (mm), 2.0 × 1.25 × 0.55 (mm), 3 2 × 1.6 × 0.6 (mm).

  The capacitor 33 is, for example, a multilayer chip capacitor (chip component), and has a structure as shown in FIG. The capacitor 33 includes a main body 33a formed in a rectangular parallelepiped made of ceramics, a pair of electrodes 33b and 33b having a U-shaped cross-section in close contact so as to cover both ends of the main body 33a, and both electrodes 33b. A plurality of metal plates 33c are provided so as to extend in 33a and overlap each other at a distance. Thus, the capacitor 33 is a chip component that uses a metal material for its structure. In addition, the metal material of the metal plate 33c generally has better thermal conductivity than ceramics. The main body 33a is covered with an insulating member. The size is 0.4 × 0.2 (mm) in length × width, 0.6 × 0.3 (mm), 1.0 × 0.5 (mm), etc., and the height is 0.2. (Mm), 0.5 (mm), 1.0 (mm), and the like. The capacitor 33 may be made of a material other than ceramics as a dielectric.

  The IC 31, the resistor 32, and the capacitor 33 are components that can be mounted on the printed circuit board 20 by a component mounting device (for example, a chip mounter). The component mounting apparatus is an automatic machine that performs an operation of attaching a predetermined component to a predetermined position (component mounting portion 23) of the printed circuit board. That is, the component mounting apparatus vacuum-sucks the component with the nozzle of the transfer head, aligns the component with the mounting location, and lowers the nozzle to land the component at the mounting location. Thus, the printed circuit board on which the circuit component 30 is mounted is sent to the heating furnace and heated, and the terminals of the circuit component 30 are soldered to the component mounting portion 23.

  One or a plurality of heat radiation components 40 are mounted on the circuit board 10 thus configured. The heat dissipation component 40 is a component that can be mounted using a component mounting apparatus. The heat radiation component 40 is preferably a ceramic chip component. For example, the chip resistor 32, the chip capacitor 33, the diode, and the transistor described above. Moreover, it is preferable that the heat radiating component 40 is a chip component using a metal material for its structure. For example, the chip capacitor 33 and the chip resistor 32 described above. Further, the heat radiation component 40 is preferably an appropriate one selected from the circuit components 30 mounted on the printed circuit board 20. In this case, selection may be made in consideration of heat dissipation, cost, size of parts, and the like.

  The heat radiating component 40 is mounted so as to be within the range of the conductor pattern 22 at a portion other than the component mounting portion 23 of the predetermined conductor pattern among the plurality of conductor patterns 22 described above. The predetermined conductor pattern is a conductor pattern having a size capable of mounting the heat dissipation component 40. In the present embodiment, the extended portion 22b1 and the conductor pattern 22c of the conductor pattern 22b are predetermined conductor patterns. This is because the two conductor patterns 22b and 22c are sufficiently wide to mount the heat dissipation component 40.

  In the conductor pattern 22b, a plurality of (eight) heat radiation components 40 are mounted on a portion other than the component mounting portion 23b, that is, the extended portion 22b1. Since the component attachment portion is not provided in the conductor pattern 22c, the heat radiation component 40 is mounted in the conductor pattern 22c. There are twelve heat dissipating parts 40. Further, in order to attach the heat radiation component 40 to these predetermined conductor patterns 22b and 22c, a solder resist is not formed on the attachment portion.

As for the heat radiation area, for example, when a chip resistor (size of 1.6 × 0.8 × 0.45 (mm)) is adopted as the heat radiating member 40, the heat radiation area is compared with the case where no chip resistor is provided. About 2.6 mm ² per piece. This is because the area of the side surface of the chip resistor (= (2 × (vertical + horizontal)) × height) = ((2 × (1.6 + 0.8)) × 0.45) = 2.16 mm ² ) Area of triangular side surface of solder fillet 55 (= (2 × (2 × ((height × height) / 2))) = (2 × (2 × ((0.45 × 0.45) / 2) ))) = 0.405 mm ² ). Therefore, for example, when 10 chip resistors are mounted on a 1 cm ² conductor pattern, the heat radiation area is only 26 mm ² (= 2.6 mm ² × 10) with respect to 100 mm ² which is the heat radiation area when no chip resistance is provided. It becomes a wide 126 mm ² . Thus, the heat dissipation component 40 needs to have a certain height in order to increase the heat dissipation area.

  The fact that the heat dissipating component 40 is mounted so as to be within the range of the predetermined conductor pattern means that the predetermined conductor pattern is not mounted so as to connect other adjacent conductor patterns separated from each other. Means.

  The predetermined conductor patterns 22b and 22c are not dedicated conductor patterns formed only for the purpose of mounting the heat dissipation component 40, but constitute a circuit on the printed circuit board 20. In order to form an attachment portion for attaching the heat dissipation component 40 to such a conductor pattern, when the printed circuit board is subjected to resist processing, the attachment portion of the heat dissipation component 40 (component attachment portion 23, through hole 24, test use) The resist may be applied except for a portion such as a pad that does not require coating. As described above, the heat dissipation component can be mounted on the existing conductor pattern with a simple design change.

2) Second Embodiment Hereinafter, a second embodiment of a circuit board according to the present invention will be described with reference to the drawings. In the second embodiment, a case where the heat generating component is a switching element will be described as an example. FIG. 6A is a top view showing an upper surface (surface on which a switching element is mounted) of the circuit board 110 on which the circuit component 30 and the heat dissipation component 40 are mounted on the printed circuit board 120. FIG. FIG. 3 is a bottom view showing a bottom surface of the circuit board 10. FIG. 7A is a top view showing the top surface of the printed circuit board 120, and FIG. 7B is a bottom view showing the bottom surface of the printed circuit board 120.

  The circuit board 110 and the printed circuit board 120 have basically the same structure as the circuit board 10 and the printed circuit board 20, and are different in the shape of the conductor pattern, the type and number of components to be mounted. FIG. 6 shows the switching element 35 and the heat radiating component 40 among the circuit component 30 mounted, and other components (IC, resistor, capacitor, etc.) are omitted. FIG. 7 is also shown corresponding to FIG.

  The switching elements 35 (four in the present embodiment) are FETs (field effect transistors) and are one of the circuit components 30. The switching element 35 is a heat generating component. The switching element 35 is an N-channel MOSFET, and receives a drain electrode 35a connected to a DC power source, a source electrode 35b grounded (connected to a ground line), and an on / off signal as a control signal. The gate electrode 35c is provided. The drain electrode 35a is a metal plate provided on the bottom surface, and is formed wide to improve heat dissipation. The source electrode 35b and the gate electrode 35c are leads (terminals) provided so as to protrude. The switching element 35 is also a component that can be mounted on the printed circuit board 20 by the above-described component mounting apparatus (for example, a chip mounter).

  The circuit board 110 is obtained by mounting the circuit component 30 (switching element 35) and the heat dissipation component 40 on the printed circuit board 120. The printed circuit board 120 includes a base material 21 and a plurality of conductor patterns 122 formed on the surface of the base material 21 with a conductive member (for example, copper foil).

  In the present embodiment, as shown in FIG. 7, there are conductor patterns 122 a to 122 d as the conductor pattern 122. The conductor pattern 122a is a conductor pattern in which a component attachment portion 123a to which the drain electrode 35a of the switching element 35 is soldered is formed at one end. A through hole 124a is formed at the other end of the conductor pattern 122a. The conductor pattern 122a functions as a power supply line connected to a power supply (DC power supply) (not shown) and has a heat dissipation function.

  The conductor pattern 122a is connected to the conductor pattern 122b formed on the back surface through a plurality of through holes 124b. The conductor pattern 122b is formed wide and has a heat dissipation function and also functions as a power supply line. The conductor pattern 122 a has a width that allows the heat dissipation component 40 to be mounted, and the conductor pattern 122 b is wider than the heat dissipation component 40.

  The conductor pattern 122c is a conductor pattern in which a part mounting portion 123c to which the source electrode 35b of the switching element 35 is soldered is formed in part. The conductor pattern 122c functions as a ground line. The conductor pattern 122d is a conductor pattern in which a component attachment portion 123d to which the gate electrode 35c of the switching element 35 is soldered is formed at one end. A through hole 124d is formed at the other end of the conductor pattern 122d, or a component mounting portion for other components is formed.

  The heat dissipation component 40 is mounted on a predetermined conductor pattern 122a (only on which the heat dissipation component 40 can be mounted), 122b. These conductor patterns 122a and 122b constitute a circuit in the printed circuit board 120.

  As is clear from the above description, according to each embodiment, one or a plurality of heat radiation components 40 are mounted on the predetermined conductor patterns 22b, 22c, 122a, 122b. The heat conduction path to the atmosphere on the conductor patterns 22b, 22c, 122a, 122b, that is, the heat radiation path (heat radiation area) can be increased. Thereby, the heat dissipation effect can be improved. Further, since the volume of the heat conduction path through which heat is conducted along the conductor patterns 22b, 22c, 122a, and 122b increases by the amount of the heat radiation component 40 mounted, the temperature of each heat conduction path is unlikely to rise. Further, when a current flows along the conductor patterns 22b, 22c, 122a, and 122b, the volume (cross-sectional area) of the current flowing portions of the conductor patterns 22b, 22c, 122a, and 122b and the heat radiation component 40 increases. It is possible to reduce the calorific value associated with.

  Further, when the chip resistor 32 and the chip capacitor 33 are used as the heat radiating component 40, the heat radiating component 40 is mounted so as to be within the range of one conductor pattern, so that the chip resistor 32 and the chip capacitor 33 are the same. Since they are connected between the potentials, even if the heat radiation component 40 is provided in the same conductor pattern, the operation of the circuit board is not affected at all. Further, even if the heat radiation component 40 breaks down, it does not affect the operation of the circuit board. Therefore, in the circuit board, the heat radiation effect can be improved without affecting the operation of the circuit board.

  Furthermore, since the heat radiating component 40 is mounted on the printed circuit board 20 (120) by the component mounting device, the heat radiating component can be mounted easily and reliably without any trouble and without any special process.

  Further, since the heat dissipation component 40 is a ceramic chip component, a sufficient heat dissipation effect can be obtained by using an inexpensive component without using a relatively expensive heat dissipation component such as a heat sink. Further, the weight can be reduced without using a relatively heavy component such as a heat sink.

  In addition, in the case where the heat radiation component 40 is a chip component (for example, a chip capacitor or a chip resistor) that uses a metal material for its structure, in addition to the action and effect when using a ceramic chip component, ceramics Since a metal material with good thermal conductivity is included, the heat dissipation can be further improved.

  Further, the predetermined conductor patterns 22b, 22c, 122a, 122b are conductor patterns electrically connected to the component mounting portion (23b or 35a) on which the heat generating components (IC31, switching element 35) are mounted. The heat radiation component 40 provided on the conductor patterns 22b, 22c, 122a and 122b can reliably and quickly radiate the heat of the heat-generating component.

  Further, the predetermined conductor patterns 22c and 122b are formed on both the surface on which the heat generating component (IC31 and switching element 35) is mounted and the back surface thereof. That is, heat can be radiated more efficiently by using not only the mounted surface but also the back surface. That is, space saving and high heat dissipation effect can be obtained.

  Further, the predetermined conductor patterns 22b, 22c, 122a, and 122b are not dedicated conductor patterns formed only for the purpose of mounting the heat dissipating component 40, but constitute circuits in the printed circuit boards 20 and 120. An efficient heat dissipation effect can be obtained by using the conductor pattern constituting the circuit as it is and by making a small change (for example, changing the resist screen mask). Moreover, since the conductor pattern which comprises a circuit can be diverted for mounting of the thermal radiation component 40, the area of a printed circuit board can be made small, maintaining or improving the thermal radiation effect.

  In addition, when there are a plurality of types of circuit component parts 30, an appropriate one is selected as the heat radiating part 40 and mounted, so that it can be used without using a relatively expensive heat radiating part such as a heat sink. Since the circuit component 30 mounted on the printed circuit board 20 (120) can be used, a sufficient heat radiation effect can be obtained at a low cost. Further, when a circuit board is manufactured using a component mounting apparatus (for example, a chip mounter), it is not necessary to use an extra parts cassette, so that labor is not required in the preparation process. Therefore, cost reduction and man-hour reduction can be achieved.

  Further, the predetermined conductor pattern may be a conductor pattern that is not electrically connected to the component mounting portion 23b on which the heat generating component (for example, the IC 31) is mounted. For example, a conductor pattern mainly having a noise prevention (shield) function and a conductor pattern mainly having a wiring function for connecting parts can be a predetermined conductor pattern. In this case, although the heat dissipation efficiency with respect to a heat-emitting component falls, a heat dissipation effect can be maintained as a circuit board.

  Further, instead of mounting the heat radiation component 40, it is conceivable to form a convex portion with solder. In this case, in order to form a convex portion having a certain height, cream solder for the circuit component 30 is used. A thicker cream solder coating screen than the coating screen is required, which increases the number of processes and requires management to form convex shaped parts (control of the amount of cream solder, ingredients, etc.). Arise. Therefore, it is advantageous in terms of process and quality to use an existing mounting component.

(A) is a top view which shows 1st Embodiment of the circuit board by this invention, (b) is a bottom view. (A) is a top view which shows the printed circuit board shown in FIG. 1, (b) is a bottom view. It is sectional drawing of a circuit board. It is sectional drawing which shows the chip resistance shown in FIG. It is sectional drawing which shows the chip capacitor shown in FIG. (A) is a top view which shows 2nd Embodiment of the circuit board by this invention, (b) is a bottom view. (A) is a top view which shows the printed circuit board shown in FIG. 6, (b) is a bottom view.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10,110 ... Circuit board, 20, 120 ... Printed circuit board, 21 ... Base material, 22, 22a-22e, 122, 122a-122d ... Conductor pattern, 22b, 22c, 122a, 122b ... Predetermined conductor pattern, 23, 23a ˜23e, 123, 123a˜123d, component mounting portion, 24, 24a, 24b, 124, 124a, 124b, through hole, 30, circuit component, 31, IC, 32, resistor, 33, capacitor, 35, switching element , 40 ... heat dissipation component, 50 ... insulating thin film, 55 ... fillet.

Claims (7)

A plurality of circuit components (30) are mounted on the component mounting portions (23, 123) formed on any of the plurality of conductor patterns (22, 122) formed on the printed circuit board (20, 120). In the circuit board (10, 110),
One or a plurality of heat dissipating components (40) that can be mounted using the component mounting apparatus are located in a portion other than the component mounting portion of the predetermined conductor pattern (22b, 22c, 122a, 122b) among the conductor patterns. A circuit board mounted so as to be within the range of the conductor pattern.   2. The circuit board according to claim 1, wherein the heat radiation component is a ceramic chip component (32).   2. The circuit board according to claim 1, wherein the heat dissipating component is a chip component (33) using a metal material for its structure.   The predetermined conductor pattern according to any one of claims 1 to 3, wherein the predetermined conductor pattern is a conductor pattern electrically connected to the component mounting portion on which the heat generating component (31, 35) is mounted. A circuit board.   The circuit board according to claim 4, wherein the predetermined conductor pattern is formed on a back surface of a surface on which the heat generating component is mounted.   The circuit board according to claim 1, wherein the predetermined conductor pattern constitutes a circuit in the printed board.   7. The circuit board according to claim 1, wherein when there are a plurality of types of the circuit component parts, an appropriate one is selected as the heat radiating part from among the plurality of types of circuit component parts. .

Images