JPH10270824A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size of an electronic device by lowering the mounting height of electronic parts and to reduce the cost of the device by reducing the number of cost elements, such as an insulating sheet, etc., which is provided for insulating a can case, etc., and making a measure to counter vibrations simpler. SOLUTION: The main body 4a of electronic parts 4 with a can case type lead terminal 6 is placed on the flat surface 3a of flat package type molded electronic parts 3 mounted on a printed board 2 and fixed to the surface 3a with a thermosetting adhesive 7 and the lead terminal 6 is bent in an L-shaped, inserted into the lead terminal inserting hole 2a of the board 2, and bonded and fixed to the board 2 with solder 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic device having an electronic component mounted on a printed circuit board, and to an arrangement of the electronic component.

[0002]

2. Description of the Related Art In recent years, electronic devices such as high-frequency-related devices, such as RF modules and BS tuners, have been required to be miniaturized. In order to satisfy such requirements, the density has been increased, and the degree thereof has been increasing. However, the can case-type electronic component 40 with lead terminals such as a quartz oscillator mounted on the electronic device needs to have a size corresponding to the oscillation frequency, and there is a limit to miniaturization. In addition, the electronic component 40 such as a quartz oscillator must be placed in a hermetically sealed case due to its characteristics, and its shape becomes elongated.

Conventionally, as shown in FIG.
The electronic device 10 is mounted on the printed circuit board 20 via the insulating sheet 50, and the lead terminals 60 are fixed to the solder lands of the printed circuit board 20 by the solder 80. Is limited by the height of the can case type electronic component 40 such as a quartz oscillator,
The housing 90 could not be made sufficiently thin. Further, in order to take measures against vibration of the elongated electronic component, it is necessary to insert the electronic component into a holder or to fix the electronic component to a part of a housing. On the other hand, the circuit of the electronic device includes many electronic elements,
As shown in FIG. 4, wide and multi-terminal I
C is often molded and mounted as a flat package electronic component 30. Therefore, the area occupied by the IC mounted on the printed circuit board 20 of the electronic device 10 is considerably large.

[0004]

In order to reduce the size of an electronic device, it is necessary to reduce the height of electronic components that determine the height of the electronic device and to increase the mounting density. Also, in order to reduce the cost of the electronic device, it is necessary to reduce the number of components such as an insulating sheet for attaching the can case to a printed circuit board while insulating the can case, and to simplify measures for vibration and the like.

[0005]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a flat package type electronic component provided on a printed circuit board and a can case type electronic device with lead terminals planted on the printed circuit board. An electronic device comprising: a flat package type electronic component, wherein the flat package type electronic component is resin-molded; Provided is an electronic device arranged to face an upper surface of a flat package type electronic component.

The present invention also provides an electronic device wherein the can case is fixed to the upper surface of the flat and the package type electronic component. In addition, an electronic device using a thermosetting adhesive is provided for fixing the can case to the upper surface of the flat and the package type electronic component. Also, the present invention provides an electronic device in which the can case type electronic component with lead terminals is a quartz oscillator. In addition, the present invention provides an electronic device in which the flat and package type electronic components are ICs.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to the drawings. FIG. 1 is a main part of a side view of an embodiment of an electronic device 1 of the present invention. The electronic component main body 4a of the can case type electronic component 4 with lead terminals is laterally opposed to the flat portion 3a on the upper surface of the molded flat package type electronic component 3 such as an IC arranged and connected on a predetermined circuit of the printed board 2. A part of the contact portion is fixed with a thermosetting adhesive 7. The lead terminal 6 protruding from the bottom surface of the electronic component body 4a is bent into an L-shape, is inserted into the lead terminal insertion hole 2a of the printed circuit board 2 at a substantially right angle, and is connected and fixed by the solder 8.

The procedure for manufacturing the electronic device 1 will be described.
First, a wide flat package type electronic component 3 molded by an IC or the like is placed at a predetermined position on a solder land of the printed circuit board 2 and the flat package type electronic component 3 is mounted.
A thermosetting adhesive 7 is applied to a predetermined position of a flat part on the upper surface of the printed circuit board 2, and the lead terminal 6 protruding from the electronic component body 4 a is bent into an L-shape to form a lead terminal insertion hole 2 a The electronic component main body 4a is placed sideways while being inserted into the thermosetting adhesive 7 applied. Next, the temperature is raised to melt the solder, and the lead terminals 6 of each mounted component are welded to the solder lands of the printed circuit board 2. At that time, the thermosetting adhesive 6 applied to the upper surface of the electronic component 3 with the can case type lead terminal is cured, and the electronic component main body 4a is fixed to the flat package electronic component 3. Since the thermosetting adhesive is used to cure the adhesive by utilizing the heat at the time of soldering, there is no need to provide a special step for bonding.

As shown in FIG. 2, the electronic device 1 manufactured in this manner is a flat package type electronic component formed by molding a low height IC or the like in a state where the high electronic component body 4a is turned sideways. 3 so that the overall height of the electronic device 1 can be reduced. In addition, since the electronic component body 4a is disposed so as to overlap the flat package type electronic component 3, the space utilization efficiency is increased, and the mounted components can be arranged at a high density, which greatly contributes to downsizing. In addition, since the electronic component body 4a is superimposed on the flat upper surface of the molded flat package type electronic component 3, a favorable arrangement without inclination can be achieved, and the lead terminal projecting from the insertion hole 2a of the lead terminal 6 to the back surface of the printed board. The protrusion dimensions of the components are also constant, and component mounting with good soldering becomes possible.

Further, since the electronic component 4 with the can case type lead terminal is superposed and adhered on the upper surface of the molded flat package type electronic component 3, the electronic component body 4a is provided.
Even if is made of metal, the insulation from the printed circuit board 2 is maintained, and components for increasing the cost such as an insulating sheet for insulating the electronic component body 4a of the can case from the printed circuit board 2 are not required. What is necessary is just what was molded with resin or glass of an insulating material. In addition, since it is fixed to the flat package with an adhesive, there is no need for a fixing holder or special fixing as a measure against vibration, which leads to cost reduction.

In addition, since the lead terminals 5 are longer than those conventionally arranged upright on a printed circuit board because the electronic components 3 are superimposed on a molded flat package type electronic component 3 such as an IC, heat generated during soldering is dissipated during propagation of the leads. Therefore, there is no effect on the electronic elements housed inside the case. The heat radiation can be adjusted by the length of the terminal lead, and the length is determined by the position of the terminal insertion hole 2a of the printed circuit board. In some cases, the heat radiation from the IC is used by the can case and the terminal leads. In general, it has been considered that the heat radiation of the IC has an adverse effect on the crystal unit, but it has been found that the steady heat generation of the IC has an effect of suppressing the influence of the variation in the outside air temperature of the crystal unit. That is, the temperature of the crystal oscillator can be kept constant by placing the crystal oscillator on the molded IC so that the temperature is biased within the range that does not affect the oscillation frequency. Was stabilized.

[0012]

According to the present invention, since the electronic component body is placed sideways on the flat package type electronic component mounted on the printed circuit board, the overall height of the electronic device can be kept low, and the area efficiency can be increased. Miniaturization has become possible. In addition, components for insulation and the like are not required, and a fixing holder for measures against vibration is not required, which leads to a reduction in cost. The oscillation frequency of the crystal unit was stabilized without being affected by the outside air temperature.

[Brief description of the drawings]

FIG. 1 is a side view of an electronic device according to an embodiment of the present invention.

FIG. 2 is a front view of the electronic device according to the embodiment of the present invention.

FIG. 3 is a side view of a conventional electronic device.

FIG. 4 is a front view of a conventional electronic device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electronic device 2 printed circuit board 3 flat package type electronic component 4 can case type electronic component with lead terminal 4 a can case 6 lead terminal 7 thermosetting adhesive

Claims (5)

[Claims] 1. An electronic device comprising: a flat package type electronic component disposed on a printed circuit board; and a can case type electronic component with lead terminals planted on the printed circuit board. The electronic component is formed by resin molding, and the can case-type electronic component with the lead terminal is configured such that the lead terminal is bent and the can case is arranged to face the upper surface of the flat package type electronic component. apparatus. 2. The electronic device according to claim 1, wherein said can case is fixed to an upper surface of said flat package type electronic component. 3. The electronic device according to claim 2, wherein the can case is fixed to the upper surface of the flat package type electronic component using a thermosetting adhesive. 4. The electronic device according to claim 1, wherein the can-case-type electronic component with a lead terminal is a quartz oscillator. 5. The flat package type electronic component is an IC.
The electronic device according to claim 1, wherein