JPH09232870A - Crystal oscillator - Google Patents

Abstract

(57) An object of the present invention is to provide a crystal oscillator capable of downsizing by increasing the versatility of an IC chip. According to the present invention, a passive element having a plurality of characteristics, for example, feedback resistance components R ₁ and R ₂ , and inverters I _{1 to} I _{5 is provided.}
The crystal oscillator 3 is connected to the inverter I ₁ on the IC chip 3 in which the feedback resistor components R ₁ and R ₂ are integrated.
Is a crystal oscillator that derives oscillation outputs having different characteristics by switching the connection between the inverter and the inverter I ₁ .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crystal oscillator composed of a crystal oscillator and an oscillation IC chip, and in particular, a feedback resistance component, a load capacitance component and a tuning connected to the crystal oscillator on the IC chip. A crystal oscillator having an IC chip capable of selecting a component having a predetermined characteristic according to an oscillation frequency by incorporating a component having a plurality of characteristics such as an inductance component in a circuit.

[0002]

2. Description of the Related Art A crystal oscillator operates based on an oscillation circuit diagram shown in FIG.

A crystal oscillator is constructed by accommodating a printed wiring board 1 on which an oscillation circuit shown in the figure is formed in a container.

The oscillation circuit was basically composed of a crystal oscillator X, an inverter I, a feedback resistor R, a load capacitance CD and CG. The inverter I has been used by integrating it into an IC chip.

In order to reduce the number of electronic components (resistors, capacitors, IC chips) mounted on the printed wiring board 1 and downsize the crystal oscillator, fixed characteristics are set according to the oscillation frequency. The resistance element, which is the feedback resistance component R, and the load capacitance components CD and CG are integrated in the IC chip 3. For example, it is a portion surrounded by a dotted line in the figure.

As a result, the oscillation circuit is mainly composed of one crystal unit X and one IC chip,
Electronic parts on the printed wiring board can be greatly reduced.

Various pads are formed on the IC chip. For example, XT ₁ pad to connect with crystal X, X
A T ₂ pad, a Q pad for deriving an oscillation output, a VDD pad (not shown) for supplying a power supply voltage, and a Vss pad for connecting to the ground potential.

The XT ₁ pad and the XT ₂ pad are connected to both ends of the crystal unit X through a predetermined wiring pattern of a printed wiring board, the VDD pad is connected to a power supply wiring pattern, and the Vss pad is ground potential. The output Q pad is connected to the oscillation output signal wiring pattern.

Each pad and the wiring pattern are connected to each other via a wire bonding thin wire and a solder bump.

[0010]

Since the above-mentioned crystal oscillator is mainly composed of one crystal resonator X and one IC chip, the structure is greatly simplified. .

However, in practice, the oscillation frequency of the crystal oscillator is a very wide oscillation frequency of several MHz to several tens of MHz due to the requirements from the electronic equipment and communication equipment to be incorporated. In addition, at present, the characteristics of the level of the oscillating signal extend over many branches.

Therefore, in order to construct an oscillation circuit for deriving an oscillation output of a specific frequency out of such a wide range of oscillation frequencies, a plurality of different types of IC chips are prepared to meet specific oscillation characteristics. Quartz crystal X and specific I
It was necessary to form an oscillation circuit by combining with a C chip.

Further, according to the output characteristics, various controls are performed on the oscillation signal output by the specific crystal unit X and the specific IC chip, for example, the specific oscillation frequency is divided, and this division is performed. When the generated signal is used as the oscillation signal, it is necessary to externally attach a circuit for dividing the frequency to the outside of the IC chip of the oscillation circuit, for example, another IC chip including a flip-flop circuit and a counter circuit. . Also, Vss
It was necessary to add a capacitance component to the outside between the pad and the wiring pattern of the ground potential in order to supplement the characteristics.

The present invention has been devised in view of the above-mentioned problems, and an object thereof is to integrate a passive element having a plurality of characteristics on an IC chip and to provide an inverter and a passive element according to a predetermined oscillation frequency. By switching the connection of (1), it is possible to provide a crystal oscillator that is compatible with a plurality of types of oscillation output characteristics with one IC chip, has high versatility, and can be downsized.

[0015]

The first invention comprises an IC chip in which a plurality of passive elements and an inverter are integrated, and a crystal oscillator connected in parallel to the inverter of the IC chip, and each passive It is a crystal oscillator that derives oscillation output with different characteristics by switching the connection between the element and the inverter.

In a second aspect of the present invention, the plurality of passive elements are feedback resistance components R ₁ , R ₂ , R _3, ...
₁ , CD _2, ..., CG ₁ , CG _2, ... And at least one component of the inductance components L ₁ , L ₂ .

According to a third aspect of the present invention, the IC chip is provided with a frequency dividing function, and the oscillation output is directly divided by the first output pad for directly deriving the oscillation output and the frequency dividing function. And a second output pad for deriving the result of the rounding.

[0018]

According to the first aspect of the present invention, by using one IC chip, the connection between the plurality of passive elements integrated on the IC chip and the inverter is selectively switched, so that the IC
The oscillation output output from the chip can be controlled to have a plurality of characteristics, for example, the oscillation frequency. For this reason, since the structure of the crystal oscillator according to the oscillation frequency can be handled by one IC chip, the versatility of the IC chip is improved and the management of the IC chip becomes very easy. It becomes easy to cope with the above, and along with this, the number of electronic parts and the like added to the outside of the IC chip is reduced, and the crystal oscillator can be miniaturized.

In the second invention, a passive element used for adjusting the oscillation frequency is exemplified, and a feedback resistance component,
The multi-oscillation frequency is controlled by one or a combination of the load capacitance component and the inductance component of the tuning circuit.

For example, in the feedback resistance component, two types of resistance components (R ₁ and R ₂ ) are integrated in the IC chip so that they can be connected in parallel to the crystal unit X.

Specifically, in the IC chip, one end of each of the resistance components R ₁ and R ₂ is connected to one end of an inverter, and the other end of each of them is connected to two selection pads S _{1 on} the surface of the IC chip. It is derived as S ₂ . These two selection pads S
_{By connecting all or one} of S ₁ and S ₂ to the other end of the inverter through the wire bonding thin wire W, the feedback resistance component R can be any one of the three resistance components. R can be connected in parallel to the inverter, and one IC chip can select a plurality of oscillation frequencies.

Similarly, for the load capacitance component, one load capacitance component, for example, two types of load capacitance components C on the CD side.
D ₁ and CD ₂ are arranged in parallel with each other.
One end of the load capacitance component CD ₁ is connected to one end of the inverter, the other end is connected to the Vss pad of the ground potential, and the other end of the load capacitance component CD ₂ is one end of the inverter. And the other end is led out to the surface of the IC chip 3 as a selection pad S ₃ . Similarly, for example, two types of load capacitance components CG ₁ and CG ₂ are arranged in parallel on the CG side, and both ends of the load capacitance component CG ₁ are connected between the other end of the inverter I and the Vss pad at the ground potential. As described above, one end of the other load capacitance component CG ₂ is connected to the other end of the inverter I, and the other end is led out to the surface of the IC chip 3 as the selection pad S ₄ . And
Connecting the selected pad S _3, S ₄ to the wiring pattern of the ground potential, or by not connecting the load capacitance component CD connected to both ends of the inverter, CG is changed. As a result, an oscillation signal having characteristics according to the usage environment of the crystal oscillator is derived.

Further, in the inductance component, the inductance component L is the same as the resistance components R ₁ and R ₂ described above.
_1, the L ₂ is arranged, I'll be selected, the inductance component of substantially the crystal resonator X, will be combined inductance component of the inductance component L _1, L ₂ is added, a plurality of high oscillation An oscillation signal with a frequency will be derived.

A third aspect of the present invention integrates not only passive elements but also active elements having a flip-flop circuit having a frequency dividing function and a counter circuit on the output side of an inverter in an IC chip and does not pass through these active elements. It has a first output pad which is output as it is and a second output pad which is processed by an active element.

For example, on the output side of the inverter, for example, a flip-flop circuit for performing one-half frequency division is integrated on an IC chip, and the output from the front stage part of the flip-flop circuit having the frequency dividing function is the first output. If it is derived from the pad Q _1, an oscillation signal of the original frequency f is obtained, and if the output is derived from the output pad Q ₂ from the subsequent stage of the flip-flop circuit, an oscillation signal having a frequency divided by 1/2 is obtained. It will be.

In the second invention and the third invention, one end of the passive element or the active element to be selected for adjusting the characteristics is an open end, and actually, it is selected on the IC chip 3. It appears as a pad. And the selection pad S ₁ ,
By selectively connecting S ₂ , S ₃ , S _4, etc. to a wiring pattern for connecting to the XT ₁ pad, XT ₂ pad or a wiring pattern for connecting to the Vss pad, selection of output pads Q ₁ , Q ₂ By connecting to an external wiring pattern that is circuitally equivalent to the crystal resonator connecting pad or the Vss pad according to the above, oscillation outputs with various oscillation characteristics can be obtained, and an external electronic device is provided outside the IC chip. The number of parts is reduced, and the miniaturization of the entire oscillator is achieved. Further, the versatility of the IC chip is improved, the management of the IC chip 3 is reduced, and the manufacturing is simplified.

The selection pad S _{1 on} the surface of the IC chip,
If S ₂ , S ₃ , and S ₄ are present on the bottom surface of the chip that is the bonding surface of the IC chip, select by adding or deleting a conductor member to a part of the wiring pattern of the printed wiring board. You can go.

As described above, according to the present invention, the IC chip is integrated with the inverter and the passive element having a plurality of characteristics, and the connection between the inverter and the passive element having a plurality of characteristics is selected and switched according to a predetermined oscillation frequency. Thus, the crystal oscillator can be made compatible with a plurality of types of oscillation frequencies with a single IC chip.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a crystal oscillator according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a crystal oscillator, FIG. 2 is a plan view around the IC chip 3, and FIG. 3 is an equivalent circuit diagram of the crystal oscillator of the present invention.

The crystal oscillator 10 of the present invention comprises a printed circuit board 1 in which a predetermined oscillation circuit is formed, that is, a wiring pattern 11 is formed, and a crystal resonator X, an IC chip 3 and other electronic parts 5 are mounted. It comprises a container body 20 for hermetically housing and sealing the printed wiring board 1.

The printed wiring board 1 is made of, for example, a multilayer ceramic circuit board, and a predetermined wiring pattern 16 is arranged on the surface or between the ceramic layers, and a concave portion 31 for accommodating the IC chip 3 is formed on the surface. There is.

The IC chip 3 is bonded to the inside of the recess 31, and each pad of the IC chip 3 has a predetermined wiring pattern 11.
To 16 through wire bonding thin wires W.

Further, a crystal resonator X is mounted on the predetermined wiring patterns 11 and 12 of the printed wiring board 1 via crystal support members 41 and 42, and each electronic component is mounted on the predetermined wiring pattern. 5 are arranged. Here, each electronic component 5 can be exemplified by, for example, a noise removing capacitor connected to the supply wiring pattern 13.

The crystal resonator X is constructed by forming vibrating electrodes on both principal surfaces of a crystal side having a thickness at a predetermined frequency and an azimuth in a thickness shear vibration mode, for example. For example, the fundamental wave frequency of the crystal unit X is 11 MHz.
The crystal unit X includes the crystal unit X support members 41 and 42.
The wiring pattern is connected to the predetermined wiring patterns 11 and 12 via a conductive adhesive such as solder. As a result, the crystal unit X
Will be installed on the printed wiring board 1 at a predetermined interval.

From the printed wiring board 1 as described above, lead terminals connected to the predetermined wiring patterns 13 to 16 penetrate the container body 20 and extend to the outside, and are required for the operation of the oscillator through these lead terminals. A power supply, a predetermined potential, a signal, etc. will be supplied and output.

The container body 20 is composed of, for example, a metal stem 21 and a metal case 22, and the joint portion thereof is firmly joined by hermetic welding, solder sealing or the like. The printed wiring board 1 described above is bonded and mounted on the metal stem.

A part of the container body can also be used as the above-mentioned printed wiring board 1. For example, prepare a multi-layer ceramic wiring board in which a recess is formed and a housing-like lid,
With the lid, the crystal unit X, the IC chip 3, and the electronic component 5 are arranged in the recess, and the lid is used to completely cover. The periphery of the opening of the lid and the periphery of the multilayer ceramic wiring board are joined by a sealing member such as low melting point glass.

Next, a connection state between the oscillation circuit formed on the printed wiring board 1 and the IC chip 3 will be described.

As an example of the oscillator circuit, as shown in FIG. 3, it is mainly composed of a crystal resonator X and one IC chip 3.

In the IC chip 3, the circuit components shown by the dotted line in FIG. 3 are integrated. For example, it is composed of _five inverters I _{1 to} I ₅ , feedback resistance components R ₁ and R ₂ capable of selectively switching the connection state with the inverter I _1, and load capacitance components CG and CD. This is formed based on the integrated formation technology of the IC chip 3, and is repeatedly formed on a semiconductor substrate such as silicon by injecting and diffusing P-type and N-type dopants, forming and removing an oxide film, and forming a metal film. it can. Then, various pads for connecting the dotted line portion in the drawing and the outside thereof are arranged on the surface of the IC chip 3. These pads include the XT ₁ pad and the XT ₁ pad that are connected to both ends of the crystal unit X.
₂ pads, VDD pad to which power is supplied (not shown in FIG. 3), Vss pad at ground potential, Q pad to output oscillation signal, INH pad to input signal for temporarily stopping oscillation signal , Feedback resistance components R ₁ , R
_It has selection pads (S ₁ pad, S ₂ pad) for selecting ₂ .

In terms of the circuit, the first inverter I ₁ is connected between the XT ₁ pad and the XT ₂ pad. Further, the input terminal of the first inverter I ₁ is connected to the Vss pad at the ground potential via the load capacitance component CG. Similarly, the output terminal of the first inverter I ₁ is connected to the Vss pad at the ground potential via the load capacitance component CD and, at the same time, is connected to the Q pad which is an output pad via the inverters I ₂ and I _3. It has been derived. further,
On the other hand the feedback end is connected to the selected pad S ₁ resistance component R ₁
Is the output terminal of the first inverter I ₁ and the load capacitance component C
It is connected to D. Similarly, the feedback resistance component R ₂ whose one end is connected to the selection pad S ₂ is connected between the output end of the first inverter I ₁ and the load capacitance component CD.

Further, two inverters I ₄ and I ₅ are arranged between the INH pad and the third inverter I ₃ .

As shown in FIG. 2, such an IC chip 3 is bonded and arranged in the recess 31 of the printed wiring board 1, and each pad is connected to the predetermined wiring patterns 11 to 16 by the wire bonding thin wire W. It

For example, the VDD pad of the IC chip 3 is
The Vss pad is connected to the power supply potential wiring pattern 13 of the printed wiring board 1, and the Vss pad is a ground potential wiring pattern 14.
, The Q pad is connected to the wiring pattern 15 for outputting an oscillation signal, the XT ₁ pad is connected to the wiring pattern 11 electrically connected to one end side of the crystal unit X, and the XT ₂ pad is , INH pad is connected to a wiring pattern 16 to which a signal for temporarily stopping the oscillation operation is input.

Next, the selection pads S ₁ and S ₂ , which are one ends of the _two feedback resistance components R ₁ and R ₂ , are connected to the XT ₁ pad in order to change the connection state with the inverter I ₁ if necessary. Similarly, it is connected to the wiring pattern 11 electrically connected to one end side of the crystal unit X by a wire bonding thin wire W or the like.

For example, the feedback resistance component Rf ₁ is 8.2K
When Ω and the feedback resistance component Rf ₂ are 5.6 KΩ, only the selection pad S ₁ is connected to the wiring pattern 11 to which the XT ₁ pad which is the input terminal of the inverter I ₁ is connected.
If the connection is made via the wire bonding thin wire W, only the feedback resistance component of the oscillation circuit becomes 8.2 kΩ due to the action of only R ₁ . Similarly, only the selection pad S ₂ is connected to the wiring pattern 1
If it is connected to 1, the feedback resistance component of the oscillation circuit will be 5.6 kΩ because only R ₂ acts. In addition, the selection pad S ₁ ,
If S ₂ is connected to the wiring pattern 11 via the wire bonding thin wire W, the feedback resistance components of the oscillation circuit are R ₁ and R
It acts with the combined resistance of ₂ and becomes 3.3 kΩ. That is, a total of three types of feedback resistance components are obtained by selectively connecting the selection pads S ₁ and S ₂ and the wiring pattern 11.

Assuming that the fundamental frequency of the crystal unit X is 11
MHz, load capacitance component C integrated in the IC chip 31
When each of D and CG is 20 pF, an output can be derived from the output pad Q under the optimum condition of oscillation of 33 to 40 MHz, for example, by connecting the selection pad S ₁ and the wiring pattern 11. Further, by connecting the selection pad S ₂ and the wiring pattern 11, the output pad Q is
The output can be derived under the optimum condition of oscillation of 0.1 to 50 MHz. Furthermore, by connecting the selection pads S ₁ and S ₂ to the wiring pattern 11, an output can be derived from the output pad Q under the optimum condition of oscillation of, for example, 50.1 to 68 MHz.

Such selection is performed by selecting pads S ₁ and S ₂
The wiring pattern 11 is connected to the wiring pattern 11 by, for example, selecting the bonding connection position of the wire bonding thin wire W, whereby the oscillation conditions of a plurality of types of frequencies can be optimized.

According to the above-described embodiment, one IC chip 3 is used to select one or both of the resistance components R ₁ and R ₂ which are passive elements.
Can achieve a crystal oscillator with three oscillation frequencies,
The versatility of the C chip 3 is improved, the management of the IC chip 3 becomes very easy, and further, it becomes easy to deal with a large amount of small quantities (multiple oscillation frequencies).

In the embodiment of FIG. 3, the output signal of the inverter I ₁ is inverted and controlled by the _two inverters I ₂ and I ₃ to change it to the original phase signal. It is necessary to stop the operation of the crystal oscillator in order to check the wiring pattern of the circuit board. Stopping of the operation of the crystal oscillator, in order to maintain the stable oscillation of the quartz resonator X, rather than stopping the operation of the inverter I _1, and stops the subsequent operation of the inverter I _1. For this reason,
The oscillating inverter I ₁ to the output are composed of odd-numbered inverters, which are inverted and controlled to change to the original phase signal.

Further, while the signal input from the INH pad is at the low level, the operation of the inverter I ₃ is stopped, and as a result, the output of the crystal oscillator is substantially stopped.

Next, another embodiment will be described based on the oscillation circuit of FIG.

In the oscillation circuit of FIG. 4, the IC chip 3
Are _five inverters I _{1 to} I ₅ , a feedback resistance component R,
Load capacitance components CD, CG, and a flip-flop element F having a frequency dividing function are integrated.

The input terminal of the flip-flop element F having the frequency dividing function is connected between the inverter I ₃ and the Q ₁ pad which is the first output pad, and the output terminal of the flip-flop element F is the second terminal. Q ₂ pad which is the output pad of the.

Therefore, the original oscillation signal is derived from the Q ₁ pad of the IC chip 3, and the output obtained by dividing the original oscillation signal into 1/2 is derived from the Q ₂ pad of the IC chip 3. .

In FIG. 4, as a circuit having a frequency dividing function,
Two flip-flop elements F are used, but two, three
It may be connected in multiple stages. By doing so, the output that is divided into ¼ and ⅛ of the original oscillation signal can be derived from the second output Q ₂ pad. Also,
By deriving an output pad from each of the plurality of flip-flop elements F ... By selecting the output pads Q ₁ pad, Q ₂ pad ... 1/2 frequency output signal,
An output signal having a frequency of 1/4, an output signal having a frequency of 1/8, etc. are obtained.

Further, as the frequency dividing method, the flip-flop element integrated in the IC chip 3 is explained, but it is also possible to combine the AND, OR gate, the counter circuit and the like integrated in the IC chip 3 and perform the frequency division by the logic circuit. .

Next, still another embodiment will be described based on the oscillation circuit of FIG.

In the oscillation circuit shown in FIG. 3, the feedback resistance component R is targeted as a selectable passive element, but in this embodiment, control can be performed by the load capacitance component which is a passive element in addition to the feedback resistance component R. It is the one.

The characteristics of the oscillation output (oscillation level) may vary depending on the power supply voltage VDD. Further, the power supply voltage VDD is often determined by various conditions on the electronic device and communication device side where the crystal oscillator is mounted.

In this embodiment, a stable oscillation output can be obtained even with different power supply voltages VDD.

The IC chip 3 has five inverters I ₁
.About.I ₅ , a feedback resistance component R, and two selectable load capacitance components CD ₁ , CD ₂ , CG ₁ , and CG ₂ are integrated.

The load capacitance component CD ₁ has one end connected to the output end of the inverter I ₁ and the other end connected to the ground potential (Vs
s). The load capacitance component CG ₁ is
One end is connected to the input end side of the inverter I ₁ , and the other end is connected to the ground potential (Vss).

The load capacitance component CG ₂ has one end connected to the input end side of the inverter I ₁ and the other end serving as a selection pad S ₃ . The load capacitance component CD ₂ has one end connected to the input side of the inverter I ₁ and the other end serving as a selection pad S ₄ .

That is, when the selection pads S ₃ and S ₄ are open, only the load capacitance components CG ₁ and CD ₁ are connected to the input side and the output side of the inverter I ₁ , respectively.

Then, the selection pad S ₃ and the selection pubber S ₄
Wiring pattern 1 of ground potential to connect Vss pad to
4 are connected to each other through the wire bonding thin wires W, the load capacitance component on the input side of the inverter I ₁ is connected to the combined capacitance of the load capacitance components CG ₁ and CG _2, and at the same time, the inverter is connected. The load capacitance component on the output side of I ₁ is connected to the combined capacitance of the load capacitance components CD ₁ and CD ₂ .

For example, load capacitances CG ₁ and CD ₁ are set to 1
If 0 pF and load capacitances CG ₂ and CD ₂ are set to 10 pF, respectively, when the power supply voltage is 3.3 V, the selection pad S ₃ ,
If S ₄ is left open and if the power supply voltage is 5 V, the selection pads S ₃ and S ₄ are connected to the wiring pattern 16 of the ground potential to stabilize the oscillation according to each power supply voltage VDD. Oscillation output can be obtained.

In this embodiment, the selection range depends on whether or not the load capacitance components CD ₂ and CG ₂ are connected. However, as in the previous embodiment, there is always one load capacitance component of three or more types. The above may be selected and connected.

From the above description of FIG. 3, FIG. 4 and FIG.
If a plurality of selectable feedback resistance components, a plurality of selectable load capacitance components, a frequency dividing function and a selectable output pad are integrated on the entire chip 3, the feedback frequency can be controlled by selecting the feedback resistance component. However, by selecting the load capacitance component, an appropriate operation corresponding to the power supply voltage can be obtained, and by selecting the output pad, a plurality of oscillation outputs in a frequency division relationship can be obtained. Since everything that was done with the attached electronic component 5 and the like can be integrated in the IC chip 3, the printed wiring board 1
The number of electronic components 5 mounted on the device can be reduced, and at the same time, the wiring pattern of the wiring pattern 11 can be simplified, which can greatly contribute to miniaturization and versatility of the crystal oscillator.

FIG. 6 shows a circuit diagram of still another embodiment of the present invention. In the above-mentioned embodiment, for the crystal unit X,
Oscillation in the frequency band of the fundamental wave level and the frequency band of the third harmonic wave level is assumed, but in this embodiment, the third harmonic wave, the fifth harmonic wave, the seventh harmonic wave, etc. can be oscillated. .

The IC chip 3 includes five inverters I ₁
~ I ₅ , feedback resistance component R, two load capacitance components CG, C
D, selectable inductance components L ₁ and L ₂ are integrated.

The inductance components L ₁ and L ₂ have one ends connected to the output end of the inverter I ₁ and the other ends serving as selection pads S ₅ and S ₆ .

For example, when the other ends of the inductance components L ₁ and L ₂ are open, that is, when the selection pads S ₅ and S ₆ have no connection, the feedback resistance component R and the load capacitance component C
Operates only with G and CD, and has a predetermined frequency (for example, third harmonic)
Will be obtained from the output pad Q.

When the selection pad S ₅ and the input end side of the inverter I ₁ , that is, the XT ₁ pad and the wiring pattern 11 are connected to each other via the wire bonding thin wire W, they are parallel to the crystal unit X. In addition, an inductance component L ₁ is added to the input pad side of the selection pad S ₆ and the inverter I ₁ , that is, when the XT ₁ pad and the wiring pattern 11 are connected via the wire bonding thin wire W. , parallel can be added to the inductance component L ₂ relative ,, crystal resonator X parallel will be the inductance component L ₂ is added to the quartz crystal resonator X, further selection pad S ₅ , S ₆ and inverter I ₁
When the input end side of, that is, the XT ₁ pad and the wiring pattern 11 are connected via the wire bonding thin wire W,
Inductance component L _{1 in} parallel with the crystal unit X
And a combined inductance component of the inductance component L ₂ is added.

As a result, the fifth harmonic of the crystal unit X, 7
By the harmonic oscillation signal being tuned and strengthened,
A crystal oscillator in which stable 5th and 7th harmonic oscillations are very stable is achieved.

In each of the above embodiments, the selection pad S ₁
Connection between to S ₆ and a predetermined wiring pattern 11 is carried out by wire bonding thin line W, recently, a flip-chip type IC chip 3 is increasing. That is, the pad is I
It is arranged on the lower surface side of the C chip 3 and is electrically connected via a solder ball or the like. In this case,
As a specific selection method, it can be performed by selectively forming connection bumps or by adding or cutting a conductive member on the wiring patterns 11, 12, 14 side.

In FIG. 3, resistance components R ₁ and R ₂
Has _one end connected to the output end of the inverter I ₁ and the other ends serving as selection pads S ₁ and S _2, and the _one ends of the resistance components R ₁ and R ₂ are used as selection pads S ₁ and S _2. , The other end may be connected to the input end of the inverter I ₁ , and the selection pads S ₁ and S ₂ may be selectively connected to the wiring pattern 12 connecting to the XT ₂ pad.
Alternatively, the wiring patterns 11 and 12 may not be used, and the selection pads S ₁ and S ₂ may be directly connected to the XT ₁ pad or the XT ₂ pad.

Similarly, in FIG. 5, the load capacitance component CD
₂ , one end of CG ₂ may be connected to the VSS pad and the other end may be used as the selection pads S ₃ and S ₄ . In this case, the selection pads S ₃ , S ₄ are XT ₁ pads, X
It is connected to the wiring patterns 11 and 12 to which the T ₂ pad is connected. Alternatively, it may be directly connected to the XT ₁ pad or the XT ₂ pad.

[0079]

As described above, according to the present invention, the passive elements forming the oscillation circuit are integrated in the IC chip so as to obtain a plurality of components, and the connection state with the inverter is selected using the selection pad. The output characteristics can be derived according to the connection state.

Therefore, since the number of electronic components connected to the outside of the IC chip can be minimized and a plurality of types of oscillation characteristics can be handled by one IC chip, the versatility of the IC chip is improved and at the same time, Miniaturization of the crystal oscillator can be achieved.

[Brief description of drawings]

FIG. 1 is a sectional view of a crystal oscillator according to the present invention.

FIG. 2 is a plan view of the periphery of the IC chip of the crystal oscillator of the present invention.

FIG. 3 is an oscillation circuit diagram of the crystal oscillator of the present invention.

FIG. 4 is an oscillation circuit diagram of another crystal oscillator of the present invention.

FIG. 5 is an oscillation circuit diagram of another crystal oscillator of the present invention.

FIG. 6 is an oscillation circuit diagram of still another crystal oscillator of the present invention.

FIG. 7 is an oscillation circuit diagram of a typical crystal oscillator.

[Explanation of symbols]

1 ... printed circuit board 2 ... container body 3 ... IC chip X ... crystal unit I ₁ ~I ₅ ... Inverter R · · · · · · · feedback resistor component CD, CG ... Load capacitance component F ... Flip-flop circuit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H03H 9/02 H03H 9/02 B 9/19 9/19 A

Claims (3)

[Claims] 1. An IC chip in which a plurality of passive elements and an inverter are integrated, and a crystal resonator connected to the inverter of the IC chip, each having different characteristics by switching the connection between each passive element and the inverter. A crystal oscillator that derives oscillation output. 2. The feedback resistance component,
The crystal oscillator according to claim 1, wherein the crystal oscillator is at least one of a load capacitance component and an inductance component. 3. The IC chip is provided with a frequency dividing function, a first output pad for directly deriving an oscillation output, and a result obtained by dividing the oscillation output by a predetermined frequency dividing rate via the frequency dividing function. The crystal oscillator according to claim 1, further comprising a second output pad for leading out.