JP3128906B2 - Piezoelectric oscillator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-molded piezoelectric oscillator.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional piezoelectric oscillator in which a piezoelectric vibrator is built and resin molded under a chip island on which an IC chip is mounted. As described above, in the prior art, the size of the chip island is sufficiently large as compared with the size of the cylindrical case of the piezoelectric vibrator to cover the entire length of the cylindrical case. That is, only the chip island regulates the cylindrical case of the piezoelectric vibrator.

[0003]

However, when the cylindrical case of the piezoelectric vibrator is large compared to the size of the chip island, the inclination of the end face of the cylindrical case of the piezoelectric vibrator at the time of mounting and the inclination of the inner lead are reduced. There is a problem in that the end face of the cylinder case comes into contact with the end face of the inner lead due to the flapping of the end face, thereby causing an electrical short circuit.

Accordingly, the present invention is to solve such a problem, and an object of the present invention is to form a piezoelectric vibrator outside the chip island by forming projecting bars on the periphery of the chip island and the suspension bar. The present invention is to provide a piezoelectric oscillator in which the inclination of the cylindrical case is suppressed and fixed.

[0005]

According to the present invention, there is provided a piezoelectric oscillator comprising:
In the piezoelectric oscillator molded with resin together with the lead frame were the IC chip and the piezoelectric vibrator mounted on the lead frame, the lead frame has a chip pad positioning said IC chip, said chip Islay
The IC chip is arranged on the upper surface side of the
The piezoelectric vibrator is arranged on the lower surface side of the chip island
And the chip island has at least one or more protruding bars , and the chip island of the piezoelectric vibrator.
Formed above a portion that does not overlap with the
-Is characterized by being in contact with the piezoelectric vibrator .
Further, the lead frame has a chip island for arranging the IC chip and a suspension bar for supporting the chip island.
The IC chip is arranged, and the chip island
Wherein the lower surface side of the de-and the piezoelectric vibrator is disposed on the suspension bar, at least one of the protruding bar - but the
A shape is formed above the portion of the piezoelectric vibrator that does not overlap with the hanging bar.
The projection bar is in contact with the piezoelectric vibrator.
Characterized in that that. Further, the lead frame having a chip pad positioning said IC chip, hanging and a bar for supporting the chip pad, and the tip
The IC chip is arranged on the upper surface side of the island,
The piezoelectric vibrator is on the lower surface side of the chip island.
The chip island and the suspension bar are formed above the piezoelectric vibrator by pressing down in a range longer than the length of the case of the piezoelectric vibrator ;
And is in contact with the piezoelectric vibrator .
Further, in the chip island or the suspension bar ,
At least one or more of the protruding bars formed, the protruding bar - Shaped above the piezoelectric vibrator further depressed than the surface and the surface of the hanging bar of the chip pad
And is in contact with the piezoelectric vibrator .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a piezoelectric oscillator according to the present invention will be described with reference to FIGS. 1 (a), 1 (b) and 2 by taking a PLCC (QFJ) package type crystal oscillator using a crystal unit as an example. .

As shown in FIGS. 1A and 1B,
An IC chip 2 is mounted on a chip island 1, and each pad of the IC chip 2 is electrically connected to an inner lead terminal 3 surrounding four sides of the chip island 1 by bonding wires 4. Rectangular AT
A crystal resonator 5 having a built-in crystal resonator element and the like has a lead terminal 6 on the chip island 1 opposite to the mounting surface of the IC chip 2, and a pad (such as a CMOS IC) for oscillating the crystal resonator of the IC chip 2. At the time of the inner lead terminal 3 connected to the gate and drain terminals).
It is fixed by a method such as welding, soldering, or a conductive adhesive. The lead frame 7 on which the crystal unit 5 and the IC chip 2 are mounted is set in a mold, and is resin-molded by transfer molding or the like while leaving the inner lead terminals 3 outside. Thereafter, the dam bar of the inner lead terminal 3 is cut and bent to obtain a PLCC package type crystal oscillator.

The point of this embodiment is that the area of the chip island 1 is smaller than that of the cylindrical case 8 of the crystal unit 5, and the end faces 9 and 10 of the cylinder case 8 of the crystal unit 5 The end faces 9 and 10 are tilted upward due to stress at the time of welding of the crystal resonator 5 and bending of the lead terminals 6, and the lead terminals near the end faces 9 and 10 are protruded outside the chip island 1. 11, 12, 1
It is easy to come in contact with 3, 14 etc. Also, lead terminals 11, 12,.
The flapping of 13 and 14 must also be taken into account. For this reason, the upward inclination of the end faces 9 and 10 of the cylindrical case 8 of the crystal unit 5 must be suppressed. Here, the protruding bar 15 is provided around the chip island 1.
By providing the tip bars 16, the end faces 9, 10 that are not pressed by the chip island 1 can be brought into contact with the projecting bars 15, 1, 2.
6 can hold it down. Thereby, the cylindrical case 8 of the crystal unit 5 and the lead terminals 11, 12, 13,
14 can be prevented from causing an electrical short circuit. Here, the projecting bar 16 extends from the suspension bar 17 that supports the chip island 1. In addition, although the quartz oscillator 5 used in this embodiment has a cylindrical shape, the outer shape of the case may be elliptical or flat.

Further, as shown in FIG. 2, the chip island 1 is subjected to depressing. The depressing process range is longer than the longitudinal dimension of the cylindrical case 8 of the crystal unit 5, and the crystal unit 5 is always attached to the chip island 1, the suspension bar 17, the projection bar 15, and the projection bar 15.
6 regulates not to tilt upward. In this embodiment, the chip island 1, the suspension bar 17, and the protruding bars 15, 16 are depressed on the same plane.
The amount of depressing is controlled so as not to contact the inner lead terminals 3 surrounding the chip island 1 on four sides.

FIG. 3 shows that the protruding bars 15, 16 are further depressed in two steps (from the plane of the chip island and the suspension bar,
In this embodiment, the cylinder-type case 8 of the crystal unit 5 and the inner lead terminal 3 surrounding the chip island 1 on four sides are securely formed by increasing the amount of depressing. You can let go.

As described above, the piezoelectric oscillator of the present invention is
Although an embodiment of the crystal oscillator having a C (QFP: QuadFlat J-Leaded Package) shape has been described, the present invention is not limited to this, and the QFP (Quad Flat Package) and QFI (Quad Flat) are not limited thereto.
Lat I-Leaded Package), QFN (Quad Flat Non-Lead)
ed Package).

[0012]

According to the piezoelectric oscillator of the present invention described above , the IC chip is arranged on the upper surface side of the chip island.
And a piezoelectric vibrator is arranged on the lower side of the chip island.
Placed on the tip island or this tip islay
The suspension bar that supports the
The raised bar is a chip island or suspension of the piezoelectric vibrator.
Formed above a portion that does not overlap with the
The bar is brought into contact with the piezoelectric vibrator so that the piezoelectric vibration
Since the inclination of the element is suppressed and fixed, the risk of short circuit failure due to contact between the piezoelectric vibrator and the inner lead terminal can be prevented, and a highly reliable piezoelectric oscillator can be obtained.

Further, the tip island and the suspension bar are
Push down over a range longer than the length of the case
Formed above the piezoelectric vibrator and in contact with the piezoelectric vibrator, the displacement at the time of mounting the piezoelectric vibrator can be absorbed, and the distance between the piezoelectric vibrator and the inner lead terminal can be reduced. The interval can be ensured. Further, the chip island or the front
At least one protruding bar is formed on the hanging bar
The projecting bar has a surface of the chip island and
Press down further than the surface of the hanging bar to
Formed above the element and abutting on the piezoelectric vibrator
The distance between the piezoelectric vibrator and the inner lead terminal
Can be more reliably achieved.

Further, by providing the protruding bar between the leads connected to the piezoelectric vibrator, the effect of noise or the like between the lead terminals of the piezoelectric vibrator is eliminated, and stable oscillation can be obtained.

Further, by providing a large number of projecting bars,
The effect of radiating heat generated from the IC chip is also increased, and a highly reliable piezoelectric oscillator can be obtained. In particular, high frequency type piezoelectric oscillators and multiple output oscillators (PLLs) have a high degree of heat generation around the oscillation of the IC chip, and the provision of protruding bars around the IC chip further enhances the heat radiation effect.

[Brief description of the drawings]

FIG. 1 shows a PLC as an embodiment of a piezoelectric oscillator according to the present invention.
The figure which shows the crystal oscillator of C (QFJ) shape. (A) is a plan view, (b) is a side view.

FIG. 2 is a diagram showing a chip island and a suspension bar depressed.

FIG. 3 is a view showing a two-stage depressed work of a protruding bar.

FIG. 4 shows PLCC as an example of a conventional piezoelectric oscillator.
The figure which shows the crystal oscillator of (QFJ) shape. (A) is a plan view. (B) is a side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Chip island 2 IC chip 3 Inner lead terminal 4 Bonding wire 5 Crystal oscillator 6 Lead terminal 7 Lead frame 8 Cylinder type case 9, 10 End face side 11, 12, 13, 14 Lead terminal 15, 16 Projecting bar 17 Hanging bar

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H03B 5/30-5/42 H01L 23/00 H01L 41/00

Claims (4)

(57) [Claims] 1. A piezoelectric oscillator and an IC are mounted on the lead frame chip and the piezoelectric vibrator molded with resin together with the lead frame, the lead frame has a chip pad to place the IC chip, the chip pad The IC chip is placed on the top side of the
And the piezoelectric layer is provided on the lower surface side of the chip island.
A vibrator is disposed, and the chip island has at least one or more protruding bars overlapping the chip island of the piezoelectric vibrator.
A piezoelectric oscillator formed above a portion where the piezoelectric vibrator is not formed, wherein the protruding bar is in contact with the piezoelectric vibrator. 2. A piezoelectric oscillator in which an IC chip and a piezoelectric vibrator mounted on a lead frame are resin-molded together with the lead frame, wherein the lead frame supports a chip island on which the IC chip is arranged, and supports the chip island. And the IC chip is arranged on the upper surface side of the chip island.
And the piezoelectric layer is provided on the lower surface side of the chip island.
A vibrator is disposed, and the suspension bar has at least one or more protruding bars.
Is a portion of the piezoelectric vibrator that does not overlap with the suspending bar.
A piezoelectric oscillator formed at an upper portion, wherein the projection bar is in contact with the piezoelectric vibrator. 3. A piezoelectric oscillator in which an IC chip and a piezoelectric vibrator mounted on a lead frame are resin-molded together with the lead frame, wherein the lead frame supports a chip island on which the IC chip is arranged, and supports the chip island. And the IC chip is arranged on the upper surface side of the chip island.
And the piezoelectric layer is provided on the lower surface side of the chip island.
Vibrator is arranged, the chip pad and the hanger bar, before press down the longer range than the length of the case of the piezoelectric vibrator
A piezoelectric vibrator formed above the piezoelectric vibrator;
A piezoelectric oscillator characterized by being in contact with a piezoelectric oscillator. Wherein the chip pad or the hanger bar
Is at least one protruding bar is formed, the protruding bar - is of the piezoelectric vibrator further depressed than the surface and the surface of the hanging bar of the chip pad
The piezoelectric oscillator according to claim 3 , wherein the piezoelectric oscillator is formed above and is in contact with the piezoelectric vibrator.