JPH07193342A - Electronic component mounting circuit board - Google Patents

Abstract

PURPOSE:To contrive a miniaturization of the whole electronic component mounting circuit board as well as to dispense with an interposition of an insulating plate or the like between metal bases at the time of a mounting of the metal bases. CONSTITUTION:A mounting board 11 is constituted of a mounting board part 12 to be formed with a circuit part and a check board part 13, which is provided with inspection terminals 15 and adjusting terminals 17. Discrete electronic components are mounted on the board part 12. The terminals 15 on the upper surface of the board part 13 are used at the time of an inspection of the performance function of the circuit part at the final stage in a state that the circuit is formed. The terminals 17 are used at the time of an adjustment of the resistance values of resistors formed on the side of the rear of the board part 12. When the adjusting work for the resistors ends, an insulating protective film 24 is provided extending over the whole surface of the board part 12. When the inspection of the performance function ends, the board part 13 is cut off from the mounting board 11 and the board 11 can be formed into a constitution, wherein it is constituted of only the board part 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board on which electronic parts are mounted to form a circuit portion.

[0002]

2. Description of the Related Art For example, in-vehicle small electronic components are generally mounted on a mounting circuit board such as a thick film substrate and mounted on an automobile in a state in which a circuit portion is formed. Along with the progress of electronic technology, various electronic components to be mounted are highly functionalized, and the scale of a circuit portion to be formed tends to increase. Therefore, in the past, in order to suppress the increase in the area of the board, for example, a board in which the wiring patterns are formed in multiple layers such as a multilayer printed board is used to suppress the increase in the size due to the wiring patterns. We are trying to improve the mounting density of electronic parts.

[0003]

By the way, in such a mounted circuit board, the operation function of the circuit portion formed by the electronic components mounted in the manufacturing process is inspected, or screen printing is performed as the mounted electronic components. In some cases, a trimming process is performed to adjust the resistance value of the resistor formed on the mounting circuit board by the manufacturing method or the like.

In this case, the process of trimming the resistor is performed, for example, by a voltage generated between the terminals in a state where a constant current is supplied from a constant current source by making electrical contact between the terminals of the resistor. A notch is formed by laser light or the like so that the resistance value of the resistor becomes a predetermined value.

Therefore, it is necessary to preliminarily form an adjusting terminal between both terminals of each resistor so that it can be contacted from the outside, but this increases the area of the mounting portion, so that mounting There was a problem in miniaturizing the circuit board.

Further, when such a thick film substrate is mounted on an automobile, the whole is mounted on a metal base in order to protect it from an adverse effect such as noise. In this case, it is mounted on the substrate. BACKGROUND ART In order to prevent an electronic component from coming into contact with a metal base to cause a short circuit or the like, an insulating protective film or the like is formed on a wiring portion.

However, as described above, when it is necessary to inspect the operation function of the circuit part in a state where the electronic part is mounted on the thick film substrate and the circuit part is formed, the inspection terminal part is left. The above-mentioned insulating protective film must be formed in this state, and when mounting on a metal base, for example, as shown in FIG.
As shown in FIG. 1, mounting was performed via an insulating plate.

That is, in FIG. 6, conductor patterns 1a, 1b, 1c are formed in a predetermined shape on both surfaces of the mounting substrate 1.
Are formed on the front surface (upper surface) of the electronic component 2 for forming a circuit portion by soldering or the like, and on the back surface (lower surface) side, the respective conductor patterns 1b,
A plurality of resistors 3 are arranged between 1c by screen printing. When the resistance value of the resistor 3 is adjusted by performing a trimming process after being formed by printing, the resin 4 as an insulating protective film covers the entire back surface, leaving a part of the conductor pattern 1c. Are arranged as follows.

This is because, as shown in the figure, a part of the conductor pattern 1c where the resistor 3 is formed is made of resin 4
After the entire circuit portion is formed in an exposed state not covered with, and before mounting on the metal base 5, the circuit portion configured by the mounted individual electronic component 2 and the resistor 3 operates normally. This is to provide an inspection terminal for performing an operational function inspection.

Therefore, when mounting on the metal base 5, for example, an insulating plate 6 is provided in order to maintain an electrically insulated state between the surface of the metal base 5 and the exposed portion of the conductor pattern 1c. Since the mounting is performed by adhering with the adhesive 7 in the state of being interposed, there are problems that the number of steps as a whole increases and the cost increases because the insulating plate 7 is used.

As described above, in the conventional electronic component mounting board, the contact terminal for trimming the resistor is provided in the circuit portion or the inspection terminal for performing the operation function inspection is exposed in the final step. Since there is a limit to reducing the size of the part in order to make it into a state, as a result, it is difficult to further reduce the size, and the number of man-hours required for mounting increases.

The present invention has been made in view of the above circumstances, and an object thereof is to save space in mounting even when a resistance value adjusting region is provided, and an insulating plate or the like for a metal base for mounting. Another object of the present invention is to provide a mounting board for an electronic component that can eliminate the need to provide.

[0013]

A mounting circuit board for electronic parts of the present invention is a mounting board part on which an electronic part forming a circuit part is mounted, and an edge part of the mounting board part which is detachable from the mounting board part. And an auxiliary substrate portion having a measuring terminal formed so as to be electrically connected to a predetermined terminal of the circuit portion that needs to be measured in the manufacturing process.

[0014]

According to the mounted circuit board for electronic parts of the present invention, when the electronic part is mounted on the mounting board part to form the circuit part, the circuit part is subjected to, for example, inspection or adjustment in the manufacturing process. When the work requires measurement between the predetermined terminals, the measurement can be performed between the measurement terminals of the auxiliary board portion. As a result, the mounting area can be reduced as compared with the conventional case in which the measurement terminals are provided on the mounting board portion, and the overall size can be reduced. In addition, even after the insulating protective film is provided on the circuit part of the mounting board part, electrical inspection between predetermined terminals of the circuit part can be performed through the measurement terminals of the auxiliary board part, so that the manufacturing process can be performed. Workability is improved. Further, when the inspection process is completed, the auxiliary board portion is cut off so that only the mounting board portion on which the circuit portion is formed can be formed, so that it is possible to reduce the size by eliminating wasted space. .

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an on-vehicle mounted circuit board will be described below with reference to FIGS. First, in FIG. 1 showing the overall surface appearance, a mounting substrate 11 having a rectangular shape is configured by using, for example, a multilayer thick film firing substrate made of a ceramic substrate, and has a large area, as described later. It is composed of a mounting board portion 12 occupying a portion and a check board portion 13 as an auxiliary board portion arranged in an L shape at an edge portion.

As shown in FIG. 1, the mounting board 11 is provided with a large number of parts on the upper surface of the mounting board portion 12 corresponding to the parts on which the individual electronic components 14 (see FIGS. 4 and 5) as electronic components are mounted. The conductor pattern 12a is formed, on the other hand, the conductor pattern is also formed on the surface of the check board portion 13, and a large number of inspection terminals 15 are arranged as measurement terminals for performing the operation function inspection. .

Further, in FIG. 2 showing the lower surface side of the mounting board 11, a large number of conductor patterns 12b and 12c forming a pair are formed in a predetermined position on the mounting board part 12, and corresponding to them, as an electronic component. A large number of resistors 16 are formed. Then, on the check board portion 13 side, a large number of adjusting terminals 17 for adjusting the resistance value as measuring terminals are also formed by the conductor pattern. The resistor 16
Is a well-known one formed by a method such as a screen printing manufacturing method, and its resistance value is adjusted in a trimming process using a laser beam or the like, which is performed through the adjusting terminal 17 described above.

FIG. 3 shows a cross section of the check board portion 13 located at the end portion of the mounting board 11. Each of the front surface side layer 18 and the back side layer 19 which compose the five-layer multilayer thick film firing substrate is shown in FIG. Is in a state in which the boundary portion with the mounting board portion 12 is cut into a V shape, and is cut off after the operation function inspection described later is completed. As shown in FIG. It is formed as a product that leaves only.

Further, each inspection terminal 1 of the check board portion 13
5 and the adjustment terminal 17 are the layers 20 to 2 in the mounting substrate 11.
It is in a state of being electrically connected to the corresponding conductor pattern of the mounting substrate portion 12 through the conductor pattern formed on the second substrate 2.

FIG. 4 is a cross-sectional view of the mounting board portion 12, showing the conductor pattern 1 corresponding to the individual electronic component 14 described above.
2a is arranged at a predetermined position and electrically connected by soldering, and the circuit portion 23 is formed by these. Further, the portion of the resistor 16 formed between the conductor patterns 12b and 12c on the back surface is covered with the insulating protective film 24 over the entire surface as shown in the figure.

Now, the mounting substrate 1 formed as described above
1, the trimming process of the resistor 16 is performed as follows. That is, the trimming work is performed in the state where the mounting board 11 is shown in FIGS. 1 and 2, that is, the state where the individual electronic components are not mounted yet. This is because the resistance value of the resistor 16 formed by screen printing on the back side does not always match the set resistance value due to variations in film thickness during screen printing, and this is normally expected. In advance, the resistance value is set to a low value.

In the trimming work, the adjustment terminals 17 corresponding to both terminals of the resistor 16 to be adjusted among the adjustment terminals 17 formed on the back surface side of the check board portion 13.
A current I is supplied from a constant current source (not shown) in the meantime, and the resistance value R (= V / I) is measured while detecting the voltage V generated between these adjustment terminals 17, and the resistance 16 of the resistor 16 is measured. A cut is made from the end in the direction perpendicular to the energizing direction by laser light or the like to narrow the energizing region. Then, the resistance value R of the resistor 16 increases, so that the trimming operation ends when the voltage V corresponding to the predetermined resistance value R is obtained.

In this way, all the resistors 16 are energized from the adjustment terminals 17 of the check board portion 13 and trimming work is performed to adjust the resistance values. Then, after that, the insulating protective film 24 is formed on the entire back surface of the mounting substrate section 12 to electrically insulate the outside.

When the individual electronic components 14 are mounted on the mounting board 11 thus formed to form the circuit section 23, the circuit section 2 is finally formed.
Perform the operation function inspection of 3. In this case, a predetermined operation function test is performed by energizing a test probe or the like (not shown) in contact with a predetermined test terminal 15 among the test terminals 15 arranged on the front surface side of the check board unit 13. Carry out.

After this, the check board portion 1 of the mounting board 11
3 is separated by folding it in a V-shaped groove,
As shown in FIG.
Only the finished product. In this case, the mounting board unit 12
Since the insulating protection film 24 is provided on the entire back surface of the metal base 25, the metal base 25 for automobile mounting is formed after this.
When mounting on (see FIG. 5), the mounting board portion 12 and the metal base 25 are electrically connected to each other even if they are mounted directly by an adhesive agent without interposing an insulating plate or the like. No more contact.

According to this embodiment, the mounting board 1 is
1, the L-shaped check board portion 13 is provided on the periphery of the mounting board portion 12, and the check board portion 13 is provided with an adjustment terminal 17 used for trimming the resistor 16 and an inspection terminal 15 for operating function inspection. Since the check board portion 13 is separated after the completion of the inspection, a product having only the mounting board portion 12 can be obtained. Since it can be mounted, space can be saved.

Further, according to this embodiment, the insulating protective film 24 can be formed over the entire back surface of the mounting substrate 12 at the stage when the trimming of the resistor 16 is completed. Since the mounting substrate 11 can be mounted by directly adhering it to the metal base 25 with an adhesive when the mounting substrate 11 is mounted on an automobile, the process of forming the insulating protective film 24 can be performed in the conventional manner without changing the order. Since it is not necessary to interpose an insulating plate as described above, the cost can be reduced and the number of steps can be reduced.

In the above embodiment, the mounting board 1
Although the case where the multilayer thick film baking substrate is used as 1 has been described, the invention is not limited to this and can be applied to the case where a double-sided thick film baking substrate (ceramic substrate) is used.

In the above embodiment, the V-shaped groove is provided in order to separate the check board 13 from the mounting board 12. However, the invention is not limited to this, and for example, perforations may be provided. Alternatively, it is possible to perform cutting with a press working machine or to use a laser working machine so that the groove or perforation is not provided.

In the above embodiment, the case where the resistor 16 as an electronic component is arranged on the back surface of the mounting substrate 13 has been described, but the resistor 16 is not provided. It can also be applied to things.

[0031]

As described above, according to the mounting circuit board for electronic parts of the present invention, the auxiliary board portion is integrally provided at the edge portion of the mounting board portion so as to be separable from the edge portion, and the auxiliary board portion is also provided. In addition, since the measurement terminal formed so as to be electrically connected to the predetermined terminal of the circuit portion that needs to be measured in the manufacturing process is provided, the electronic component is mounted on the mounting board portion to form the circuit portion. In this state, if it is necessary to perform measurement between the predetermined terminals in the manufacturing process for the circuit part in a process such as inspection or adjustment, the measurement can be performed between the measurement terminals of the auxiliary board part, As a result, the mounting area can be reduced compared to the conventional method in which the measurement terminals are provided on the mounting board section, and the overall size can be reduced, and an insulating protective film is provided on the circuit section of the mounting board section. Even after It is possible to perform such electrical inspection of between predetermined terminals of the circuit section through the measuring terminals of the substrate section,
Workability in the manufacturing process is improved, and when the inspection process is completed, the auxiliary board portion is cut off, so that only the mounting board portion having the circuit portion can be configured. It has an excellent effect that it can be miniaturized by eliminating the problem.

[Brief description of drawings]

FIG. 1 is an external perspective view of a substrate surface (upper surface) showing an embodiment of the present invention.

FIG. 2 is an external perspective view of the back surface (bottom surface) of the same.

FIG. 3 is a vertical sectional side view of the check board portion.

FIG. 4 is a vertical sectional side view of a mounting board unit.

FIG. 5 is an external perspective view showing a mounting board mounted on a metal base.

FIG. 6 is a vertical cross-sectional side view showing a conventional example mounted on a metal base.

[Explanation of symbols]

11 is a mounting board, 12 is a mounting board part, 12a, 12b,
12c is a conductor pattern, 13 is a check board portion (auxiliary board portion), 14 is an individual electronic component (electronic component), 15 is an inspection terminal (measurement terminal), 16 is a resistor (electronic component), and 17 is an adjustment terminal (measurement). Terminals), 23 is a circuit portion, 24 is an insulating protective film, and 25 is a metal base.

Claims (1)

[Claims] 1. A mounting board portion on which an electronic component forming a circuit portion is mounted, and the circuit portion which is integrally provided at an edge portion of the mounting board portion so as to be separable from the mounting portion, and which requires measurement in a manufacturing process. A mounting circuit board for an electronic component, the auxiliary circuit board part having a measuring terminal formed so as to be electrically connected to a predetermined terminal of the electronic circuit board.