JP5918546B2 - Temperature compensated crystal oscillator - Google Patents

Description

  The present invention relates to a temperature-compensated crystal oscillator that performs temperature compensation, and more particularly to a temperature-compensated crystal oscillator that suppresses frequency fluctuations that occur immediately after power supply.

[Conventional technology]
A conventional temperature compensated crystal oscillator (TCXO) is obtained by adding a temperature compensation circuit to a voltage controlled oscillator to reduce frequency fluctuation due to a change in ambient temperature.
In the conventional temperature-compensated crystal oscillator, the frequency may drift (fluctuate or fluctuate) immediately after the power is supplied, and the frequency drift characteristic changes due to the heat generated when the power is turned on.

A conventional method for compensating the frequency drift characteristic has been proposed, and the amount of compensation has been constant (see Patent Document 1).
However, the frequency drift characteristic in the temperature compensated crystal oscillator has a wave characteristic, and thus cannot be compensated by the conventional means.

[Frequency drift characteristics: Fig. 17]
The frequency drift characteristic will be described with reference to FIG. FIG. 17 is a diagram showing frequency drift characteristics at a high temperature (+ 85 ° C.). In FIG. 17, the frequency (Freq.) On the vertical axis is represented by Linear, and the time (Time (s)) on the horizontal axis is represented by Log.
Although frequency drift occurs after the power is turned on, a portion surrounded by a thick wavy line portion in FIG.

[Related technologies]
As related prior art, Japanese Patent Laid-Open No. 10-224148, “Piezoelectric Oscillator” (Toyo Tsushinki Co., Ltd.) [Patent Document 1], Japanese Patent Laid-Open No. 07-254818, “Voltage Controlled Oscillator” (Toshiba Co., Ltd.) [Patent Document 2], Japanese Patent Application Laid-Open No. 2003-258551, “Temperature Compensation Circuit of Oscillation Circuit and its Temperature Compensation Method” (Seiko Epson Corporation) [Patent Document 3], Japanese Patent Application Laid-Open No. 2008-271355 “ “Temperature Compensated Crystal Oscillator” (Nippon Denpa Kogyo Co., Ltd.) [Patent Document 4], JP 09-018234 “Temperature Compensated Piezoelectric Oscillator” (Seiko Epson Corporation) [Patent Document 5], JP 07-162233 A "Digital Temperature Compensated Crystal Oscillator" (Meidensha et al.) [Patent Document 6], Japanese Patent Application Laid-Open No. 11-355044, "Voltage Controlled Oscillator" ( Sin Electric Co., Ltd.) is [Patent Document 7].

Patent Document 1 discloses an anode terminal of a variable-capacitance diode in a voltage-controlled piezoelectric oscillator composed of an amplifying unit including a transistor, a resistor and a capacitor, a piezoelectric vibrator, a variable-capacitance diode, and a control voltage unit including a resistor and a capacitor. It has been shown that the frequency starting characteristic of the piezoelectric oscillation circuit can be shortened by making the voltage of 1 variable with time.
Patent Document 2 discloses that in a voltage controlled oscillator, temperature drift compensation is performed for a linearity best point of control characteristics of a control voltage by a temperature drift compensation circuit.

In Patent Document 3, in an oscillation circuit, a correction interval determination circuit obtains a temperature change based on a temperature detected from a temperature sensor, and determines a correction interval for correcting the oscillation frequency of the oscillation circuit according to the temperature change. It is shown.
In Patent Document 4, in a temperature compensated crystal oscillator, a compensation error of a temperature compensation voltage based on a temperature difference between a detection temperature due to heat generation at the time of activation of an IC chip and an operating temperature of a crystal piece is measured in advance, and the compensation error is calculated. It is shown that a start-up correction voltage to be corrected is applied to the voltage variable capacitance element.

Patent Document 5 shows a configuration in which a part of a compensation circuit is outside a package in a temperature compensated piezoelectric oscillator.
Patent Document 6 shows a configuration in which a current is controlled by a switch circuit in a digital temperature compensated crystal oscillator in order to incorporate a temperature compensation circuit in an IC chip.
Patent Document 7 shows that in a voltage controlled oscillator, a variable capacitance circuit is built in an IC chip, and the circuit is configured by a variable capacitance diode, a capacitor, and the like.

JP-A-10-224148 Japanese Patent Application Laid-Open No. 07-254818 JP 2003-258551 A JP 2008-271355 A JP 09-018234 A Japanese Patent Laid-Open No. 07-162233 Japanese Patent Laid-Open No. 11-355044

  However, the conventional temperature-compensated crystal oscillator does not take into account the swell characteristic of the frequency drift characteristic after power-on, and does not compensate for the swell characteristic of the frequency drift characteristic. .

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a temperature-compensated crystal oscillator capable of suppressing the swell characteristic of the frequency drift characteristic.

The present invention for solving the problems of the above conventional example includes a crystal resonator, an amplifier connected in parallel to the crystal resonator, and a voltage at which the cathode side of the varicap diode is connected to the input side and output side of the amplifier. a crystal oscillator having a variable capacitance element, a temperature compensation circuit for outputting a control voltage for temperature compensation, the first period in which the frequency drift characteristics after power by the features falls steeply frequency drift characteristics, smooth a second period of decreasing the divides the third period to gradually increase the first frequency drift for outputting a control voltage for frequency compensation to the cathode of varicap diode voltage variable capacitance element in the first period a compensation circuit, a second frequency drift for outputting a control voltage for frequency compensation to the cathode of varicap diode voltage variable capacitance element in the second period A compensation circuit, and having a third frequency drift compensation circuit for outputting a control voltage for frequency compensation to the anode side of the varicap diodes of the voltage-variable capacitive element in the third period.
Further, according to the present invention, the frequency compensation characteristic obtained by the control voltage output from the first frequency drift compensation circuit has a steep rise in the first period, and is output from the second frequency drift compensation circuit. The frequency compensation characteristic obtained by the control voltage gradually increases in the second period, and the frequency compensation characteristic obtained by the control voltage output by the third frequency drift compensation circuit is gentle in the third period. It is characterized by being lowered and stabilized.

The present invention is a crystal oscillator having a crystal resonator, an amplifier connected in parallel to the crystal resonator, and a voltage variable capacitance element having a cathode side of a varicap diode connected to an input side and an output side of the amplifier. , A temperature compensation circuit that outputs a control voltage for temperature compensation, and a first period in which the frequency drift characteristic falls sharply after power-on due to the characteristics of the frequency drift characteristic , a second period in which the frequency drift falls gently, and rises gently A second frequency drift compensation circuit that outputs a control voltage for frequency compensation in the second period to the cathode side of the varicap diode of the voltage variable capacitance element , and frequency compensation in the third period It is characterized by having a third frequency drift compensation circuit for outputting a control voltage to the anode side of the varicap diodes of the voltage-variable capacitance element .

The present invention, the frequency compensation characteristic obtained by the control voltage the second frequency drift compensation circuit outputs are gently above Noborisu shall in the second period, control the third frequency drift compensation circuit outputs frequency compensation characteristic obtained by the voltage, and characterized in that the stabilized drop-off down gently in the third period.

  According to the present invention, in the above temperature compensated crystal oscillator, the frequency drift compensation circuit is configured such that a constant voltage is applied to one end of the resistor, the other end of the resistor is connected to one end of the capacitor, the other end of the capacitor is grounded, An amplifier for amplifying the voltage between the capacitors is provided, and when the whole is packaged, a resistor and a capacitor of the frequency drift compensation circuit are provided outside the package.

  According to the present invention, in the above temperature compensated crystal oscillator, the frequency drift compensation circuit includes an amplifier in which a constant current source circuit and a capacitor are connected in series, and a voltage between the constant current source circuit and the capacitor is amplified. A diode anode is connected to the stage, and a cathode of the diode is grounded.

  The present invention is characterized in that, in the temperature compensated crystal oscillator, when the whole is packaged, a capacitor is provided outside the package.

According to the present invention, a temperature compensation circuit for outputting a control voltage for temperature compensation, a first period in which the frequency drift characteristics after power-on by the features of the frequency drift characteristic falls steeply, second to gently lowered period, divided into third periods that gradually rises, the first frequency drift compensation circuit for outputting a control voltage for frequency compensation to the cathode of varicap diode voltage variable capacitance element in the first period, the second A second frequency drift compensation circuit for outputting a control voltage for frequency compensation in the period of time to the cathode side of the varicap diode of the voltage variable capacitance element , and a control voltage for frequency compensation in the third period of time for the variable capacitance of the voltage variable capacitance element . since the crystal oscillator having a third frequency drift compensation circuit for outputting to the anode side of the diode, the frequency drift characteristics There is an effect capable of suppressing the kneading properties.

1 is a configuration diagram of a temperature compensated crystal oscillator according to an embodiment of the present invention. FIG. It is a figure which shows the frequency characteristic required for waviness compensation. FIG. 6 is a diagram showing compensation characteristics in a time t1 region. FIG. 6 is a diagram showing compensation characteristics in a time t2 region. FIG. 6 is a diagram showing compensation characteristics in a time t3 region. It is the figure which showed the correction characteristic for offset (Offset). It is a circuit diagram of a frequency drift compensation circuit. It is a figure which shows a frequency drift compensation circuit output voltage (Linear). It is a figure which shows a frequency drift compensation circuit output voltage (Log). It is a figure which shows the compensation frequency characteristic of a cathode input. It is a figure which shows the compensation frequency characteristic of an anode input. It is a figure which shows adjustment of a voltage level. It is a figure which shows adjustment of a time constant. When this oscillator is packaged, a t1 to t3 adjusting unit is provided outside the package. When this oscillator is packaged, a t2 to t3 adjusting section is provided outside the package. It is a circuit diagram of another frequency drift compensation circuit. It is a figure which shows a frequency drift characteristic.

Embodiments of the present invention will be described with reference to the drawings.
[Outline of the embodiment]
The temperature compensated crystal oscillator according to the embodiment of the present invention includes a first frequency drift compensation circuit, a second frequency drift compensation circuit, and a third frequency drift compensation circuit. The frequency drift characteristic is compensated for by applying the offset voltage in each of the three periods, and the flatness can be realized over time, and the swell characteristic of the frequency drift characteristic is suppressed. It can be done.

[Temperature compensated crystal oscillator: Fig. 1]
A temperature compensated crystal oscillator according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a configuration diagram of a temperature compensated crystal oscillator according to an embodiment of the present invention.
As shown in FIG. 1, a temperature compensated crystal oscillator (present oscillator) according to an embodiment of the present invention includes a temperature compensation circuit 1, an AFC (Auto Frequency Control) circuit 2, a frequency drift compensation circuit A3a, a frequency Drift compensation circuit B3b, frequency drift compensation circuit C3c, adder (Adder) 4, crystal resonator 5, inverter IC (Integrated Circuit) 6, voltage variable capacitance elements 7a and 7b, and buffer (Buff1) 8 And an output terminal (OUTPUT1) 9 basically.

[Each oscillator part]
Each part of the oscillator will be specifically described.
The temperature compensation circuit 1 detects the temperature around the crystal unit 5 and outputs a temperature compensation control voltage (temperature compensation control voltage) to the adder 4 according to the detected temperature.
The AFC (Auto Frequency Control) circuit 2 outputs a control voltage (oscillation frequency control voltage) for causing a specific frequency to oscillate from the output terminal 9 to the adder 4.

[Frequency drift compensation circuit]
The frequency drift compensation circuits (A, B, C) 3a, 3b, 3c have a characteristic configuration in the embodiment. For the purpose of swell compensation, the frequency of the oscillator depends on times t1, t2, and t3, which will be described later. A control voltage (frequency drift compensation control voltage) for compensating the drift characteristic is output to both ends of the crystal resonator 5 and the inverter IC6.
The functions of the frequency drift compensation circuits (A, B, C) 3a, 3b, 3c, the specific configuration of the frequency drift compensation circuit 3, and the compensation operation will be described later.

An adder 4 adds the temperature compensation control voltage from the temperature compensation circuit 1 and the oscillation frequency control voltage from the AFC circuit 2 and outputs the sum to the varicap diodes D1 and D2.
The addition in the adder 4 may be performed by weighting each input voltage.

The crystal unit 5 oscillates at a resonance frequency determined by the load capacitance viewed from both ends of the crystal unit.
An inverter IC (Integrated Circuit) 6 amplifies the oscillation frequency of the crystal unit 5, inverts the phase, and outputs it to the buffer 8.

The voltage variable capacitance elements 7a and 7b are composed of, for example, varicap diodes D1 and D2, and change the capacitance according to the applied voltage, and change the load capacitance of the crystal resonator 5 to adjust the oscillation frequency.
Specifically, one end of a parallel circuit of a resistor R1 and a capacitor C3 is connected to the anode side of the varicap diode D1 of the voltage variable capacitance element 7a, and the other end is grounded.
One end of the parallel circuit of the resistor R2 and the capacitor C4 is connected to the anode side of the varicap diode D2 of the voltage variable capacitance element 7b, and the other end is grounded.

  Then, the compensation voltage from the frequency drift compensation circuit C3c is applied to the anode side of the varicap diodes D1 and D2, and the control voltage from the adder 4 is applied to the cathode side of the varicap diodes D1 and D2. A compensation voltage from the circuit A3a and the frequency drift compensation circuit B3b is applied, and a voltage for offset adjustment from the offset voltage adjustment circuit is applied.

The buffer (Buff1) 8 is a signal amplifier that amplifies the oscillation frequency from the inverter IC 6 and outputs it to the output terminals 9a and 9b.
The output terminal 9 is a terminal that outputs an oscillation signal of the present oscillator.

[Frequency characteristics required for swell compensation: Fig. 2]
FIG. 2 is a diagram illustrating frequency characteristics necessary for swell compensation. In FIG. 2, the vertical axis frequency (Freq.) Is Linear, and the horizontal axis time (Time (s)) is Log.
As shown in FIG. 2, the characteristics of the frequency fluctuation with the passage of time after power-on can be divided (divided) into time (period) regions of t1, t2, and t3.
It can be seen that the frequency rises steeply in the time t1 region, rises gently in the time t2 region, gently falls in the time t3 region, and stabilizes after the time T1.

[Compensation characteristics in each time domain: FIGS. 3, 4, 5, and 6]
FIG. 3 is a diagram showing compensation characteristics in the time t1 region, FIG. 4 is a diagram showing compensation properties in the time t2 region, and FIG. 5 is a diagram showing compensation properties in the time t3 region. It is. FIG. 6 is a diagram showing correction characteristics for an offset. In each figure, the vertical axis frequency (Freq.) Is Linear, and the horizontal axis time (Times (s)) is Log.
The characteristics shown in FIG. 2 can be realized by adding the compensation characteristics shown in FIGS.

[Frequency drift compensation circuit: Fig. 7]
Next, the frequency drift compensation circuit will be described with reference to FIG. FIG. 7 is a circuit diagram example of a frequency drift compensation circuit.
As shown in FIG. 7, the frequency drift compensation circuit includes a resistor 31 to which a fixed voltage is supplied at one end, a capacitor 32 having one end connected to the other end of the resistor 31, and the other end of the capacitor 32 grounded. And an amplifier (AMP) 33 for inputting and amplifying the voltage at a point between the other end of the capacitor 32 and one end of the capacitor 32.
By adjusting the fixed voltage, the value of the resistor 31, the value of the capacitor 32, and the gain of the amplifier (AMP) 33, a voltage for compensating the frequency drift characteristic is output from the amplifier 33.

[Frequency drift compensation circuit output voltage: FIGS. 8 and 9]
The output voltage from the frequency drift compensation circuit will be described with reference to FIGS. FIG. 8 is a diagram showing the frequency drift compensation circuit output voltage (Linear), and FIG. 9 is a diagram showing the frequency drift compensation circuit output voltage (Log).
In FIG. 8, the vertical axis represents voltage, and the horizontal axis represents time as Linear. In FIG. 9, the vertical axis represents voltage, and the horizontal axis represented time as Log.

[Compensation frequency of varicap diode input: FIGS. 10 and 11]
FIG. 10 shows the compensation frequency characteristics when the voltage shown in FIG. 9 is input to the cathode side of the varicap diodes D1 and D2. FIG. 10 is a diagram illustrating the compensation frequency characteristics of the cathode input.
FIG. 11 shows the compensation frequency characteristics when the voltage shown in FIG. 9 is input to the anode side of the varicap diodes D1 and D2. FIG. 11 is a diagram illustrating a compensation frequency characteristic of the anode input.

The frequency drift compensation circuit A3a outputs a voltage having a compensation frequency in the period t1 to the cathode side of the varicap diodes D1 and D2.
The frequency drift compensation circuit B3b outputs a voltage having a compensation frequency in the period t2 to the cathode side of the varicap diodes D1 and D2.
The frequency drift compensation circuit C3c outputs a voltage having a compensation frequency in the period t3 to the anode side of the varicap diodes D1 and D2.

  Also, the outputs of the frequency drift compensation circuits A3a, B3b, C3c are inverted, the inverted outputs of the frequency drift compensation circuits A3a, B3b are output to the anode side, and the inverted outputs of the frequency drift compensation circuit C3c are output to the cathode side. It is also possible to add each of them before outputting to the anode or cathode side.

[Voltage level adjustment: FIG. 12]
As adjustment of the compensation characteristic, the voltage level can be adjusted in the arrow direction (vertical direction) in FIG. 12 by adjusting the fixed voltage in the frequency drift compensation circuit or the gain of the amplifier (AMP) 33. FIG. 12 is a diagram illustrating adjustment of the voltage level.

[Adjustment of time constant: Fig. 13]
Further, as adjustment of the compensation characteristic, the time constant can be adjusted in the arrow direction (lateral direction) in FIG. 13 by adjusting the capacitor (C) and the resistor (R) in the frequency drift compensation circuit. FIG. 13 is a diagram illustrating adjustment of the time constant.

According to this oscillator, the frequency drift by the frequency drift compensation circuit A3a, the frequency drift compensation circuit B3b, and the frequency drift compensation circuit C3c, and further, by applying the offset voltage, the undulation of the frequency drift characteristic is compensated, and the flat characteristic with time. There is an effect that can be realized.
Note that the period t1 is an early time, and may be less important in the early stabilization of the frequency, and the frequency drift compensation circuit A3a may be omitted in order to reduce the area of the IC chip.

[Package Circuit According to Another First Embodiment: FIG. 14]
This shows an example in which the resistor and the capacitor of the t1 to t3 adjusting unit are provided outside the package when the present oscillator (TCXO) is packaged. FIG. 14 shows a case where the t1 to t3 adjusting section is provided outside the package when the oscillator is packaged. However, the fixed voltage, AMP, is built in the package.
In this way, a large time constant can be adjusted by providing the circuit portion for adjusting the swell to the outside of the package.

[Package Circuit According to Another Second Embodiment: FIG. 15]
When this oscillator (TCXO) is packaged, the t1 adjustment unit has a relatively small time constant, so the t1 adjustment unit is built in the IC, and the resistors and capacitors of the t2 to t3 adjustment units are provided outside the package. An example is given. FIG. 15 shows a case where the t2 to t3 adjusting unit is provided outside the package when the oscillator is packaged. However, the fixed voltage, AMP, is built in the package.

[Another frequency drift compensation circuit: FIG. 16]
Another frequency drift compensation circuit will be described with reference to FIG. FIG. 16 is a circuit diagram of another frequency drift compensation circuit.
In another frequency drift compensation circuit, as shown in FIG. 16, a constant current source circuit 34 and a capacitor 32 are connected in series, the other end of the capacitor 32 is grounded, and the constant current source circuit 34 and the capacitor 32 are connected to each other. The voltage at the point is inputted to the input terminal of the amplifier (AMP) 33, the anode of the diode 35 is connected to the input terminal, and the cathode of the diode 35 is grounded.
The circuit in FIG. 16 is realized without using a resistor.
Moreover, a large time constant can be adjusted by setting the current of the constant current source circuit 34 to a minute current.

  In the frequency drift compensation circuit of FIG. 16, the time constant is adjusted by adjusting the current flowing through the constant current source circuit 34 and the capacitance of the capacitor 32, and the gain of the AMP 33 is adjusted. Thus, the voltage level is adjusted.

  Note that the frequency drift compensation circuit of FIG. 16 can be housed in one package. Further, as shown in FIG. 14, the frequency drift compensation circuit of FIG. 16 may be provided with a capacitor or the like of the t1 to t3 adjusting section outside the package, and as shown in FIG. 15, t2 to t3. A capacitor or the like of the adjustment unit may be provided outside the package.

[Effect of the embodiment]
According to this oscillator, the frequency drift compensation circuit A3a, the frequency drift compensation circuit B3b, and the frequency drift compensation circuit C3c perform frequency compensation in the periods t1, t2, and t3, respectively, and further, by applying the offset voltage, the frequency drift characteristics are improved. It is possible to compensate for the undulation, to realize a flat characteristic with time, and to suppress the undulation characteristic of the frequency drift characteristic.

  The present invention is suitable for a temperature-compensated crystal oscillator that can suppress the swell characteristic of a temperature-compensated crystal oscillator that generates a swell characteristic of a frequency drift characteristic.

  1 ... temperature compensation circuit, 2 ... AFC circuit, 3a ... frequency drift compensation circuit A, 3b ... frequency drift compensation circuit B, 3c ... frequency drift compensation circuit C, 4 ... addition 5 ... Quartz crystal, 6 ... Inverter IC, 7a, 7b ... Voltage variable capacitor, 8 ... Buffer, 9 ... Output terminal, 31 ... Resistance, 32 .. .Capacitor 33 ... Amplifier (AMP) 34 ... Constant current source circuit 35 ... Diode

Claims (7)

A crystal oscillator having a crystal resonator, an amplifier connected in parallel to the crystal resonator, and a voltage variable capacitance element connected to a cathode side of a varicap diode on an input side and an output side of the amplifier,
A temperature compensation circuit that outputs a control voltage for performing temperature compensation; and
The frequency drift characteristic is divided into a first period in which the frequency drift characteristic falls sharply after power-on , a second period in which the frequency drift falls gently, and a third period in which the frequency drift rises gently. A first frequency drift compensation circuit for outputting a control voltage for frequency compensation to the cathode side of the varicap diode of the voltage variable capacitance element;
A second frequency drift compensation circuit that outputs a control voltage for frequency compensation in the second period to the cathode side of the varicap diode of the voltage variable capacitance element;
And a third frequency drift compensation circuit for outputting a control voltage for frequency compensation in the third period to the anode side of the varicap diode of the voltage variable capacitance element. Frequency compensation characteristic obtained by the control voltage first frequency drift compensation circuit outputs is made of steep rising retriever in the first period,
Frequency compensation characteristic obtained by the control voltage the second frequency drift compensation circuit outputs are gently above Noborisu shall in the second period,
Frequency compensation characteristic obtained by the control voltage where the third frequency drift compensation circuit outputs a crystal oscillator of claim 1 Symbol placement and characterized in that the stabilized drop-off down gently in the third period . A crystal oscillator having a crystal resonator, an amplifier connected in parallel to the crystal resonator, and a voltage variable capacitance element connected to a cathode side of a varicap diode on an input side and an output side of the amplifier,
A temperature compensation circuit that outputs a control voltage for performing temperature compensation; and
According to the characteristics of the frequency drift characteristic, it is divided into a first period in which the frequency drift characteristic falls sharply after power-on , a second period in which the frequency drift falls gently, and a third period in which the frequency drift rises gently. A second frequency drift compensation circuit that outputs a control voltage for frequency compensation to the cathode side of the varicap diode of the voltage variable capacitance element;
And a third frequency drift compensation circuit for outputting a control voltage for frequency compensation in the third period to the anode side of the varicap diode of the voltage variable capacitance element. Frequency compensation characteristic obtained by the control voltage the second frequency drift compensation circuit outputs are gently above Noborisu shall in the second period,
Frequency compensation characteristic obtained by the control voltage where the third frequency drift compensation circuit outputs a crystal oscillator according to claim 3 Symbol mounting, characterized in that it is intended to stabilize drop-off down gently in the third period . In the frequency drift compensation circuit, a constant voltage is applied to one end of a resistor, the other end of the resistor is connected to one end of a capacitor, the other end of the capacitor is grounded, and the voltage between the resistor and the capacitor is amplified. With an amplifier,
If the whole package, the frequency drift compensation circuit the resistor and crystal oscillator according to any one of claims 1 to 4 said capacitor, characterized in that provided outside of the package. The frequency drift compensation circuit includes a constant current source circuit and a capacitor connected in series, and an amplifier that amplifies a voltage between the constant current source circuit and the capacitor, and an anode of a diode is connected to an input stage of the amplifier, any description of the crystal oscillator according to claim 1 to 4, characterized in that the cathode of the diode is grounded. 7. The crystal oscillator according to claim 6 , wherein when the whole is packaged, a capacitor is provided outside the package.

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