JP2962966B2 - Matching circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a matching circuit device for matching a crystal filter or an amplifier of a radio device.

[0002]

2. Description of the Related Art FIG. 5 is a circuit diagram showing a conventional matching circuit device. In the figure, reference numeral 1 denotes a crystal filter in an intermediate frequency band of a receiving unit of a wireless device, and reference numeral 2 denotes a matching circuit connected to an input unit of the crystal filter 1.
In the matching circuit 2, reference numeral 3 denotes a variable inductive element connected between the input of the crystal filter 1 and the ground. Reference numeral 4 denotes a connection between the input of the crystal filter 1 and the input terminal of the matching circuit 2. The fixed capacitance element 5 connected between them is a fixed capacitance element connected between the input terminal of the matching circuit 2 and the ground.

Next, the operation will be described. The matching of the input portion of the crystal filter 1 is performed by adjusting the resonance point of the matching circuit 2 by the variable inductive element 3. Here, since the matching circuit 2 is housed in the housing of the wireless device, when adjusting the resonance point, the housing is opened to adjust the variable inductive element 3. Therefore, when the matching state changes when the housing is closed, it is necessary to adjust the variable induction element 3 in consideration of the change in advance, and this adjustment work is complicated and requires skill. Was.

FIG. 6 is a circuit diagram showing a conventional filter circuit device described in, for example, Japanese Utility Model Laid-Open Publication No. 3-66218 for explaining the adjustment of the resonance point by the variable capacitance element. In the figure, 6 to 8 are fixed inductive elements connected in series to each other, and 9 to 12 are fixed capacitive elements connected to both ends of each of the fixed inductive elements 6 to 8, respectively. 13,
Numeral 14 denotes a variable capacitance element such as a varicap which is connected in series to the fixed capacitance element 10 or 11 and whose capacitance value is controlled by an applied control voltage, and 15 and 16 are controlled by the variable capacitance element 13 or 14. This is a resistor for applying a voltage.

Next, the operation will be described. Resistor 15,
When the control voltage applied to the variable capacitance elements 13 and 14 is changed by 16, the capacitance value of the variable capacitance elements 13 and 14 changes. Therefore, the combined capacitance value of the fixed capacitance element 10 and the variable capacitance element 13 and the combined capacitance value of the fixed capacitance element 11 and the variable capacitance element 14 change, and the resonance point changes accordingly, and the cutoff frequency changes. It becomes possible. In addition, as a document describing a technique related to such adjustment of the resonance point, for example, Japanese Patent Laid-Open No.
-73118, JP-A-62-2612, JP-A-62-274811, JP-A-63-7727.
No. 5 publication.

[0006]

Since the conventional matching circuit device is configured as described above, if the matching state changes when the housing is closed, the variable inductive element taking into account the change is considered in advance. 3, the adjustment work requires complicated skill. In addition, a variable capacitance element is incorporated in the matching circuit 2 and the matching state is adjusted by adjusting the capacitance value of the variable capacitance element. Although it is conceivable that the adjustment is performed while the filter is closed, there is a problem that it is not possible to sufficiently cope with a case where the impedance of the crystal filter 1 changes due to a temperature change.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a matching circuit device capable of adjusting a matching state with a housing closed and sufficiently coping with a temperature change. With the goal.

[0008]

According to a first aspect of the present invention, there is provided a matching circuit device comprising: a variable voltage source for adding a variable capacitance element to a matching circuit and generating a control voltage applied to the variable capacitance element; A control unit that controls the voltage value of the control voltage based on the setting data from the keypad, a memory that stores an optimum one of the setting data as a setting value, and a correction data for temperature-compensating the control voltage. It has a temperature compensating part applied to the part.

According to a second aspect of the present invention, in the matching circuit device according to the second aspect of the present invention, the control section determines a voltage value of the control voltage output from the variable voltage source based on setting data input externally through serial communication. To control.

A third aspect of the present invention provides a matching circuit device in which a matching circuit is connected to a crystal filter.

A fourth aspect of the present invention provides a matching circuit device in which a matching circuit is connected to an amplifier.

[0012]

According to the first aspect of the present invention, the control unit controls the control voltage applied to the variable capacitance element by the variable voltage source based on the setting data from the keypad, and sets an optimum one of the setting data. By storing the value in the memory and compensating the temperature of the control voltage based on the correction data from the temperature compensator, the matching state can be adjusted with the housing closed, and it is possible to cope with temperature changes. Realizing a simple matching circuit device.

Further, the control unit according to the second aspect of the present invention automatically stores the set value in the memory by controlling the voltage value of the control voltage based on the set data input from the outside by serial communication. It is possible to perform it.

According to the third aspect of the present invention, the matching state of the crystal filter is adjusted by connecting the matching circuit to the input or output of the crystal filter.

Further, in the matching circuit device according to the present invention, the matching state of the amplifier is adjusted by connecting the matching circuit to the amplifier.

[0016]

[Embodiment 1] Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In FIG. 1, 1 is a crystal filter, 2 is a matching circuit, 4 and 5 are fixed capacitance elements,
Are the same as or similar to those of the related art in which the same reference numerals are given, and detailed description thereof will be omitted. Also, 17
Is a variable capacitance element such as a varicap which is connected in series to the fixed capacitance element 5 and whose capacitance is controlled by an applied control voltage, and 18 is a fixed induction element arranged in place of the variable induction element 3 , The matching circuit 2 includes the variable capacitance element 17, the fixed induction element 18, and the fixed capacitance elements 4,
5.

Reference numeral 19 denotes a D / A converter as a variable voltage source for generating a control voltage to be applied to the variable capacitance element 17 of the matching circuit 2. Reference numeral 20 denotes a control voltage output from the D / A converter 19. This is a resistor applied to the variable capacitance element 17. Reference numeral 21 denotes a central processing unit (hereinafter, referred to as a central processing unit) that acts as a control unit that controls a voltage value of a control voltage output from the D / A converter 19 based on input setting data and performs overall control of the wireless device. Reference numeral 22 denotes a keypad for inputting setting data to the CPU 21. The keypad 22 is also used for inputting other data of the wireless device. Reference numeral 23 denotes a memory for storing, as a set value, the optimum one of the set data input from the keypad 22, and reference numeral 24 denotes a temperature compensating unit for providing the CPU 21 with correction data for temperature compensating the control voltage.

FIG. 2 is a block diagram showing the structure of the temperature compensator 24. In the figure, reference numeral 25 denotes a thermistor whose resistance value changes with temperature, and 26 denotes a resistor connected in series with the thermistor 25. 27, a value obtained by dividing the voltage E by the thermistor 25 and the resistor 26 is digitized, and the digitized value is used as correction data by the CPU 27.
An A / D converter for sending to the A / D converter 21.

Next, the operation will be described. When the user operates the keypad 22, predetermined setting data is transferred to the CP.
It is input to U21. On the other hand, correction data corresponding to the temperature at that time is input to the CPU 21 from the temperature compensating unit 24, and the CPU 21 uses the correction data to set the data from the keypad 22 according to the temperature characteristics of the crystal filter 1. The correction is made, and the correction value is sent to the D / A converter 19. The A / D converter 19 converts the correction value into an analog voltage value, and applies it to the variable capacitance element 17 of the matching circuit 2 via the resistor 20 as a control voltage. Therefore, when the CPU 21 and the D / A converter 19 have an 8-bit configuration and the maximum applied voltage of the variable capacitor 17 is V, the variable capacitor 17
The application of the control voltage can be set in 256 steps.

The variable capacitance element 17 to which the control voltage has been applied via the resistor 20 has its capacitance value set to a value defined by the control voltage.
The input portion of the crystal filter 1 is matched by a resonance point determined by the combined capacitance of the fixed capacitor 5 and the capacitance of the fixed capacitor 4 and the inductance of the fixed inductive element 18. Here, when the matching is in an optimal state, the received field strength display value (hereinafter referred to as RSSI) output from the receiving unit of the wireless device becomes maximum. Therefore, the setting data at the time when the RSSI becomes maximum is
Then, the set value is stored in the memory 23. Hereafter, CP
U21 controls the D / A converter 19 by correcting the set value stored in the memory 23 with the correction data from the temperature compensator 24.

As described above, according to this matching circuit device,
The matching state of the matching circuit 2 can be adjusted while the housing is closed, and even if the impedance of the crystal filter 1 changes with temperature, the temperature change is corrected by the temperature compensating unit 24. It can be easily compensated with data.

Embodiment 2 FIG. In the above embodiment, the case where the matching circuit 2 is connected to the input unit of the crystal filter 1 has been described. However, the matching circuit 2 may be connected to the output unit of the crystal filter 1. As long as correction data by a digital signal corresponding to the temperature can be obtained, the correction data is not limited to the one shown in FIG. 2, and even if another temperature sensor using a thermoelectromotive force or the like is used. In each case, the same effects as in the above embodiment can be obtained.

Embodiment 3 FIG. In the above embodiment, the CPU
Although the description has been given of the case of inputting the setting data to the keypad of the wireless device, the setting data may be input from the outside by serial communication. FIG. 3 is a block diagram showing such an embodiment. Corresponding portions are denoted by the same reference numerals as in FIG. 1, and description thereof will be omitted. In the figure, reference numeral 28 denotes a CPU as a control unit to which setting data is externally input by serial communication, and 29 denotes such a CPU.
Wireless device including a matching circuit device according to claim 1. Reference numeral 30 denotes a voltmeter for measuring the RSSI output from the wireless device 29. Reference numeral 31 denotes a CPU 28 which reads the measured value of the voltmeter while sequentially transmitting the generated setting data by serial communication.
Is a personal computer to be input.

Next, the operation will be described. In this case, the basic operation is the same as in the first embodiment. That is, CP
U28 corrects the setting data inputted by serial communication from the personal computer 31 with the correction data from the temperature compensating unit 24, controls the D / A converter 19, and corresponds to the variable capacitance element 17 in the matching circuit 2. The applied control voltage is applied. The personal computer 31 sequentially changes the setting data to be output, and sequentially changes the RS data output from the receiving unit of the wireless device 29 measured by the voltmeter 30.
The value of the SI is read, and the setting data having the maximum value of the RSSI is stored in the memory 23 as the setting value. CP
The U 28 thereafter controls the D / A converter 19 by correcting the set value stored in the memory 23 with the correction data from the temperature compensating unit 24.

As a result, the adjustment of the matching state of the matching circuit 2 can be performed automatically without performing the setting data input from the keypad 22 one by one.

Embodiment 4 FIG. Further, in the first embodiment, the case where the matching circuit is connected to the crystal filter of the wireless device has been described. FIG. 4 is a block diagram showing such an embodiment. Corresponding portions are denoted by the same reference numerals as in FIG. 1, and description thereof will be omitted. In the figure, 3
Reference numeral 2 denotes an amplifier having a matching circuit 2 connected to an input portion thereof. In this case, the matching circuit 2 has a fixed capacitance element 5 connected to an input portion of the amplifier 32. The operation is the same as that of the first embodiment, and the description thereof is omitted.

[0027]

As described above, according to the first aspect of the present invention, the control voltage applied to the variable capacitance element from the variable voltage source is controlled based on the setting data from the keypad,
The optimum value in the setting data is stored in the memory as a setting value, and the temperature of the control voltage is compensated by the correction data from the temperature compensating unit. Therefore, the matching state is adjusted with the housing closed. Is possible,
Further, even when the characteristics change depending on the temperature, there is an effect that a matching circuit device that can easily compensate for the temperature change with the correction data from the temperature compensating unit can be obtained.

Further, according to the invention described in claim 2, since it is configured to control the voltage value of the control voltage based on the setting data inputted from the outside to the control unit by a serial communication, Ri by keypad There is an effect that the adjustment of the matching state can be automatically performed without inputting the setting data one by one.

According to the third aspect of the present invention, since the matching circuit is configured to be connected to the input portion or the output portion of the crystal filter, the matching state of the crystal filter can be adjusted with the housing closed. effective.

According to the fourth aspect of the present invention, since the matching circuit is connected to the amplifier, there is an effect that the matching state of the amplifier can be adjusted while the housing is closed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a matching circuit device according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a temperature compensator in the embodiment.

FIG. 3 is a block diagram showing a matching circuit device according to Embodiment 3 of the present invention.

FIG. 4 is a block diagram showing a matching circuit device according to Embodiment 4 of the present invention.

FIG. 5 is a circuit diagram showing a conventional matching circuit device.

FIG. 6 is a circuit diagram showing a conventional filter circuit device for explaining adjustment of a resonance point by a variable capacitance element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crystal filter 2 Matching circuit 4 Fixed capacitance element 5 Fixed capacitance element 17 Variable capacitance element 18 Fixed induction element 19 Variable voltage source (D / A converter) 21 Control part (CPU) 22 Keypad 23 Memory 24 Temperature compensation part 28 Control part (CPU) 32 Amplifier

Claims (4)

(57) [Claims] 1. A fixed induction element, a fixed capacitance element, and a variable capacitance element whose capacitance value changes according to an applied control voltage, and a resonance point thereof is controlled by a change in the capacitance value of the variable capacitance element. A matching circuit, a variable voltage source for generating the control voltage to be applied to the variable capacitance element of the matching circuit, and a setting input from a keypad.
Data and correction data generated by the temperature compensator
The control voltage output from the variable voltage source based on the
Comprising of a control unit for controlling a voltage value, and a memory for storing a set value as the optimum setting in data input from the keypad, the control unit may set the memory value
Is stored, the stored set value and the
Based on the correction data generated by the temperature compensator,
The voltage value of the control voltage output from the variable voltage source is controlled.
And a matching circuit device. 2. A fixed induction element, a fixed capacitance element, and a variable capacitance element whose capacitance value changes according to an applied control voltage, and a resonance point thereof is controlled by a change in the capacitance value of the variable capacitance element. A matching circuit, a variable voltage source that generates the control voltage to be applied to the variable capacitance element of the matching circuit, and an external input through serial communication.
Setting data and the compensation generated by the temperature compensator.
Before being output from the variable voltage source based on the positive data
And a control unit for controlling the voltage value of the serial control voltage, and a memory for storing a set value as the optimal in the setting data inputted from the external, the control unit is set in the memory
After the set value is stored, the stored set value and
Based on the correction data generated by the temperature compensator
The voltage of the control voltage output from the variable voltage source
A matching circuit device characterized by controlling a value . 3. The matching circuit device according to claim 1, wherein the matching circuit is connected to an input or an output of a crystal filter of the wireless device. 4. The matching circuit device according to claim 1, wherein the matching circuit is connected to an amplifier of a wireless device.