Crystal oscillator

Abstract

The crystal oscillator of the present invention includes a crystal vibrator disposed on the upper side of a container having a lower housing portion with an opening thereunder, and an IC integrated circuit chip for controlling the oscillation operation of the crystal oscillator installed in the lower housing portion. , the filling resin injected into the encapsulation area of ​​the IC integrated circuit chip, the external terminal electrodes formed on the four corners below the container and connected with the described IC integrated circuit chip, wherein the lower containing portion, in each external There are two pairs of protruding protrusions at positions facing each other between the terminal electrodes; on the bottom surface of the pair of protrusions facing each other among the two pairs of protrusions, there is a device for monitoring the crystal. The oscillation characteristics of the vibrator are monitored by electrode pads. Since the monitor electrode pads are arranged on the bottom surfaces of the pair of mutually facing protrusions, the interval between the monitor electrode pads can be lengthened, and the stray capacitance generated therebetween can also be controlled.

Description

technical field [0001] The present invention relates to a crystal oscillator used in mobile communication equipment, especially a crystal oscillator that can be directly mounted on a printed circuit board for use. Background technique [0002] A crystal oscillator is a very important component for generating an oscillation frequency that controls the transmission and reception of information in mobile communication devices, etc. Such crystal oscillators used in mobile communication equipment and the like must also be miniaturized in accordance with the miniaturization of mobile communication equipment. [0003] Furthermore, even when used in an environment where the ambient temperature varies greatly, the frequency must be stabilized. For this reason, it is necessary to carry out a kind of temperature compensation on the inherent temperature-frequency characteristic of the crystal oscillator. This temperature compensation is to make the frequency of the natural temperature...

AI Technical Summary

Problems solved by technology

However, in the conventional structure, as the miniaturization is realized, the distance between the monitoring electrode pads becomes closer. In this way, due to the stray capacitance generated between the monitoring electrode pads, the measurement of the characteristics of the crystal oscillator becomes difficult. be adversely affected

[0010] And, when a pair of monitoring electrode pads are arranged in the central part of the housing part, when the IC integrated circuit chip is arranged, when the base film resin and sealing resin are injected into the housing part from the periphery of the IC integrated circuit chip, the In the gap between the bottom surface of the part and the package surface of the IC chip, due to the unevenness formed by the thickness of the monitoring electrode pad in the central part, the flow of the filling resin is hindered, so that the air is easy to stay in the IC chip. The packaging part

That is to say, although the thickness of the monitoring electrode pad itself is not so thick, because the gap between the bottom surface of the housing part and the packaging surface of the IC chip is inherently narrow, the influence on the monitoring electrode pad increases accordingly. Big

In this case, once the air stays in the packaging part of the IC chip, the bonding strength of the IC chip will deteriorate.

[0011] Moreover, since the space of the housing portion becomes narrow with the realization of miniaturization, the gap between the inner wall of the housing portion and the periphery of the IC chip becomes narrow.

In this way, the operation of assembling the IC integrated circuit chip, the operation of injecting the filling resin such as the base film resin and the sealing resin become difficult, and the filling resin is also difficult to spread into the packaging surface of the IC integrated circuit chip.

[0012] Moreover, since the planar shape of the package side of the external wiring board of the crystal oscillator becomes smaller with the realization of miniaturization, the area of ​​the external terminal electrodes arranged around the housing portion is also reduced. The mounting strength on the line substrate is weakened

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