JP2017017422A - equalizer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an equalizer enabling a characteristic change while suppressing increased cost and work time.SOLUTION: An equalizer 100 includes: a series circuit 6 disposed between a main line 1 and the ground 2 and composed of a series connection of a resistor 3, a transmission line 4 and a tip short circuit line 5; a tip open line 7 having one end 7a connected to the connection end of the transmission line 4 with the tip short circuit line 5, whereas the side of another end 7b being bent; and an inductor 8 having one end 8a connected to the connection side of the transmission line 4, the tip short circuit line 5 and the tip open line 7, whereas another end 8b connected to the other end 7b side of the tip open line 7.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an equalizer that compensates for gain frequency characteristics of a high-frequency device.

  In high frequency equipment, gain flatness is often required in the frequency band to be used. A high-frequency device is composed of components such as an amplifier and a plurality of semiconductor components, but these components have different frequency characteristics, so that it is rare that the flatness of the gain can be ensured only by combining them. Therefore, an equalizer is added as a functional circuit, and gain flatness is ensured by giving the equalizer characteristics opposite to the frequency characteristics of components such as an amplifier and a plurality of semiconductor components. In Patent Document 1, a circuit in which a resistor, a transmission line, and a tip short-circuited line are connected in series is inserted between a main line through which a high-frequency signal propagates and the ground, and a tip-open line is inserted between the transmission line and the inductor. An equalizer provided with is disclosed. On the other hand, since the frequency characteristics of components such as an amplifier and a plurality of semiconductor components vary depending on the production lot, it is desirable that the equalizer characteristics can be changed correspondingly. In this method, a conductor pattern is provided around the open end line for characteristic adjustment in the circuit described above, and the open end line and the conductor pattern are connected with a gold wire, or the open end line and the conductor pattern are connected. By cutting the gold wire, it is possible to change the length of the open-ended line. As another method, as shown in Embodiment 3 of Patent Document 1, a variable capacitance element is added to the circuit, and the characteristic is changed by changing the capacitance value by changing the bias voltage of the variable capacitance element. This is possible.

Japanese Patent No. 3852603

  However, in the method of changing the characteristics of the equalizer by providing a conductor pattern, it is necessary to connect a gold wire. Therefore, a device for wire bonding is required to adjust the gain characteristics during the test, and the time required for the work Which increases the cost. Also, in the method of changing the equalizer characteristics by changing the capacitance value of the variable capacitance element, it takes time to adjust the bias voltage, and additional circuit elements are added, resulting in an increase in cost and an increase in circuit size. There is a problem that arises. Therefore, it is necessary to develop an equalizer that can arbitrarily change characteristics while suppressing an increase in cost and work time.

  The present invention has been made in view of the above, and an object thereof is to obtain an equalizer capable of changing characteristics while suppressing an increase in cost and an increase in work time.

  In order to solve the above-described problems and achieve the object, an equalizer according to the present invention is provided between a main line through which a signal propagates and a ground, and connects a resistor, a transmission line, and a tip short-circuit line in series. A series circuit composed of: one end connected to the connection end of the transmission line and the tip short-circuited line, the other end side being bent, a tip open line; one end being the transmission line, the tip short-circuited line, and the tip An inductor connected to the connection side with the open line and having the other end connected to the other end of the open end line, and one end of the open end line before the inductor is disconnected from the open end line The electrical length from the open end line to the other end of the open end line is Φa, and the electrical length from one end of the open end line to the other end of the open end line after the inductor is cut from the open end line is Φb. Φa Characterized in that it is a .phi.b.

  According to the present invention, it is possible to change characteristics while suppressing an increase in cost and an increase in work time.

Configuration diagram of equalizer according to Embodiment 1 The figure showing the equivalent circuit of the equalizer which concerns on Embodiment 1 The figure for demonstrating the electrical length in the front-end | tip open line of the equalizer which concerns on Embodiment 1. FIG. The figure which shows the frequency characteristic of the equalizer which concerns on Embodiment 1, the gain frequency characteristic of a high frequency apparatus, and the gain frequency characteristic of the high frequency apparatus after correction | amendment The figure which shows the frequency characteristic when the inductor is connected in the equalizer which concerns on Embodiment 1, and the frequency characteristic when an inductor is cut | disconnected The figure showing the electrical length of the open end line when changing the position where the inductor is connected in the equalizer according to the first embodiment The figure which shows a frequency characteristic when the position where an inductor is connected in the equalizer which concerns on Embodiment 1 is changed. Configuration diagram of equalizer according to Embodiment 2 The figure which shows the frequency characteristic when two inductors are connected in the equalizer which concerns on Embodiment 2, and the frequency characteristic when both or one of two inductors is cut | disconnected.

  Below, the equalizer which concerns on embodiment of this invention is demonstrated in detail based on drawing. Note that the present invention is not limited to the embodiments.

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of an equalizer according to the first embodiment. The equalizer 100 is provided between a main line 1 through which a signal propagates and a ground 2, and includes a series circuit 6 configured by connecting a resistor 3, a transmission line 4, and a tip short-circuit line 5 in series, and one end 7 a Connected to the connection end of the transmission line 4 and the short-circuited short-circuit line 5, the open-ended line 7 is bent at the other end 7 b side, and the one-end 8 a is connected to the transmission line 4, the short-circuited short-circuit line 5, and the open-ended line 7. And an inductor 8 connected to the other end 7b side of the open-ended line 7 at the other end 8b. In FIG. 1, the names of the respective portions of the open end line 7 to which the inductor 8 is connected are referred to as a base end portion 71, a bent portion 72, and a front end portion 73. The base end portion 71 is a region from one end 7 a of the open end line 7 to the connection end with the one end 8 a of the inductor 8, and the bent portion 72 is from the connection end with the one end 8 a of the inductor 8 to the other end 8 b of the inductor 8. The distal end 73 is a region from the connection end with the other end 8 b of the inductor 8 to the other end 7 b of the end open line 7. An output terminal of a high-frequency device (not shown) is connected to the input terminal 9 on one end side of the main line 1. A signal output from the high-frequency device is input from the input terminal 9 to the equalizer 100 and output from the output terminal 10. The equalizer 100 has a frequency characteristic that can compensate for the gain frequency characteristic of a high-frequency device to obtain a flat gain characteristic as a whole. In FIG. 1, the bent portion 72 has an inverted U shape, but the bent portion 72 may have a C shape or an L shape.

  FIG. 2 is a diagram illustrating an equivalent circuit of the equalizer according to the first embodiment. As described above, since the open-ended line 7 is connected between the transmission line 4 and the short-circuited short line 5, the parallel circuit of the short-circuited line 5 and the open-ended line 7 can be equivalently regarded as a capacitor. . Therefore, the transmission line 4, the tip short-circuit line 5, and the tip open line 7 are composed of an inductor L caused by the transmission line 4 and a capacitor C caused by the tip short-circuit line 5 and the tip open line 7, as in the equivalent circuit of FIG. 2. The series resonance circuit 11 can be considered. When the inductor L and the capacitor C of the series resonance circuit 11 are in series resonance, the impedance when the resistor 3 side is viewed from the main line 1 is equal to the value of the resistor 3. For this reason, the impedance when the inductor L and the capacitor C are in series resonance is lower than the impedance when the inductor L and the capacitor C are not in series resonance.

  FIG. 3 is a diagram for explaining the electrical length of the open end line of the equalizer according to the first embodiment. FIG. 3A shows the electrical length Φa when the inductor 8 is connected to the open-ended line 7, and the electrical length Φa is the open-ended line before the inductor 8 is disconnected from the open-ended line 7. 7 represents the electrical length from one end 7a of the terminal 7 to the other end 7b of the open end line 7. More specifically, the electrical length Φa represents the electrical length from one end 7 a of the open end line 7 to the other end 7 b of the open end line 7 through the base end portion 71, the inductor 8, and the front end portion 73. FIG. 3B shows the electrical length Φb after the inductor 8 is disconnected from the open-ended line 7, and the electrical length Φb is the open-ended line 7 after the inductor 8 is disconnected from the open-ended line 7. Represents the electrical length from one end 7a to the other end 7b of the open-ended line 7. More specifically, the electrical length Φa represents the electrical length from one end 7 a of the open end line 7 to the other end 7 b of the open end line 7 through the base end portion 71, the bent portion 72, and the front end portion 73. The equalizer 100 according to the first embodiment is configured to satisfy the relationship of electrical length Φa <electrical length Φb. According to the equalizer 100 according to the first embodiment, the electrical length of the open-ended line 7 can be easily changed depending on whether the inductor 8 is disconnected from the open-ended line 7, and resonance when the inductor 8 is disconnected. The frequency moves to the low frequency side.

  Next, the relationship between the frequency characteristic of the equalizer 100 according to the first embodiment and the gain frequency characteristic of the high-frequency device will be described with reference to FIGS. 4 and 5.

  FIG. 4 is a diagram showing a frequency characteristic of the equalizer according to the first embodiment, a gain frequency characteristic of the high frequency device, and a gain frequency characteristic of the corrected high frequency device. FIG. 4A shows the frequency characteristics of the equalizer 100, where the vertical axis represents amplitude and the horizontal axis represents frequency. As shown in FIG. 4A, in the equalizer 100, the loss near the resonance frequency fc is the largest, and the loss decreases as the distance from the resonance frequency fc increases. FIG. 4B shows gain frequency characteristics of a high-frequency device having a convex characteristic within a required band. The vertical axis represents gain and the horizontal axis represents frequency. In the gain frequency characteristic shown in FIG. 4B, the gain is small at both ends of the lower limit frequency and the upper limit frequency of the required frequency band, and the gain is increased near the center frequency. FIG. 4C shows the gain frequency characteristic after the gain frequency characteristic of FIG. 4B is corrected with the frequency characteristic of FIG. 4A. The vertical axis represents the gain and the horizontal axis represents the frequency. . By connecting the equalizer 100 to the high frequency device, the gain frequency characteristic of the high frequency device is compensated, and a flat gain characteristic as shown in FIG. 4C can be obtained.

  FIG. 5 is a diagram showing a frequency characteristic when the inductor is connected in the equalizer according to the first embodiment and a frequency characteristic when the inductor is disconnected. The frequency characteristic indicated by symbol a is a characteristic when the inductor 8 is disconnected, and the frequency characteristic indicated by symbol b is a characteristic when the inductor 8 is connected. As described above, in the equalizer 100 according to the first embodiment, the electrical length of the open-ended line 7 when the inductor 8 is connected is shorter than the electrical length of the open-ended line 7 when the inductor 8 is disconnected. . When the inductor 8 is cut and the electrical length of the open-ended line 7 is increased, the capacitance value of the capacitor C is relatively increased in the series resonance circuit 11 shown in FIG. Since the resonance frequency fc of the resonance circuit is proportional to 1 / √LC, the capacitance value of the capacitor C increases and moves to a low band.

  FIG. 6 is a diagram illustrating the electrical length of the open-ended line when the position where the inductor is connected is changed in the equalizer according to the first embodiment. The inductor 8 shown in FIG. 6A is connected to the bent portion 72 side with respect to the inductor 8 shown in FIG. The electrical length Φa11 in FIG. 6A represents the electrical length from one end 7a of the open end line 7 to the other end 7b of the open end line 7 when the inductor 8 is connected to the position in FIG. . Similarly, the electrical length Φa12 in FIG. 6B is the electrical length from one end 7a of the open end line 7 to the other end 7b of the open end line 7 when the inductor 8 is connected to the position in FIG. Represents. By changing the connection position of the inductor 8 in this way, the electrical length Φa12 becomes shorter than the electrical length Φa11. The magnitude relationship between the electrical length Φb shown in FIG. 3B and the electrical length Φa12 and the electrical length Φa11 shown in FIG. 6 is electrical length Φa12 <electrical length Φa11 <electrical length Φb.

  FIG. 7 is a diagram showing frequency characteristics when the position to which the inductor is connected is changed in the equalizer according to the first embodiment. The frequency characteristic indicated by symbol a is a characteristic when the inductor 8 is cut. The frequency characteristic indicated by symbol b is a characteristic when the inductor 8 is connected to the position shown in FIG. 6A, that is, when the electrical length is Φa11. The frequency characteristic indicated by symbol c is a characteristic when the inductor 8 is connected to the position shown in FIG. 6B, that is, when the electrical length is Φa12. By changing the connection position of the inductor 8 in this way, the amount of change in the resonance frequency can be set finely.

  The method of changing the gain characteristic in the conventional equalizer is to provide a conductor pattern around the open-ended line and connect the open-ended line and the conductive pattern with a gold wire, or cut the connected gold wire. By reducing the electrical length of the open-ended line and reducing the capacitance value of the resonance circuit, the resonance frequency is moved to a high range. On the other hand, in the equalizer 100 according to the first embodiment, the resonance frequency can be moved to a low band by using a gold wire for the inductor 8 and cutting the gold wire. Therefore, it is possible to arbitrarily change the resonance frequency to the high frequency side or the low frequency side by cutting one of the two gold wires after combining the conventional method and the equalizer 100 of the first embodiment. is there.

  On the other hand, the conventional method of changing the gain characteristics requires not only the gold wire cutting work but also the gold wire connecting work as described above, and therefore a wire bonding apparatus is required when adjusting the gain characteristics during the test. Therefore, there is a problem in that the working time and cost are increased. On the other hand, in the equalizer 100 according to the first embodiment, the gain characteristic can be adjusted only by cutting the inductor 8. Therefore, the gain flatness of the high-frequency device can be easily optimized in accordance with the characteristics of the semiconductor component used as compared with the conventional method of changing the gain characteristics.

Embodiment 2. FIG.
FIG. 8 is a block diagram of an equalizer according to Embodiment 2 of the present invention. In the equalizer 200 of the second embodiment, a plurality of inductors are used instead of the inductor 8 of the first embodiment, and in the second embodiment, two first inductors 81 and a second inductor 82 are used. In the equalizer 200 according to the second embodiment, the first inductor 81 in the plurality of inductors has one end 81a connected to the connection side of the transmission line 4, the tip short-circuit line 5 and the tip open line 7, and the other end 81b. The second inductor 82 in the plurality of inductors connected to the other end 7b side of the open end line 7 is in parallel with the first inductor 81, and one end 82a is the transmission line 4, the end short line 5, and the end open line 7. The other end 82b is connected to the other end 7b side of the open end line 7. The electrical length from one end 7a of the open-ended line 7 to the other end 7b of the open-ended line 7 before both the first inductor 81 and the second inductor 82 are cut is Φa1, The electrical length from one end 7a of the open end line 7 to the other end 7b of the open end line 7 before the second inductor 82 is disconnected and after the first inductor 81 is disconnected from the open end line 7 is expressed as Φa2. When the electrical length after both the first inductor 81 and the second inductor 82 are disconnected from the open-ended line 7 is Φb, the equalizer 200 has an electrical length Φa1 <electrical length Φa2 <electrical length Φb. Configured to satisfy relationships.

  In the illustrated example, one end 82 a of the second inductor 82 is connected between the connection end of the open end line 7 and one end 81 a of the first inductor 81 to the bent portion 72. The other end 82 b of the second inductor 82 is connected between the bent portion 72 and the connection end of the open end line 7 and the other end 81 b of the first inductor 81.

  FIG. 9 is a diagram illustrating a frequency characteristic when two inductors are connected in the equalizer according to the second embodiment, and a frequency characteristic when both or one of the two inductors is disconnected. The frequency characteristic indicated by symbol a is a characteristic when both the first inductor 81 and the second inductor 82 are disconnected, and the frequency characteristic indicated by symbol b is the connection of the second inductor 82 and disconnection of the first inductor 81. The frequency characteristic indicated by symbol c is a characteristic when both the first inductor 81 and the second inductor 82 are connected. As described above, the equalizer 200 according to the second embodiment is configured to satisfy the relationship of electrical length Φa1 <electrical length Φa2 <electrical length Φb. Therefore, for example, the electrical length when only the first inductor 81 is cut is longer than the electrical length when the first inductor 81 and the second inductor 82 are connected, and the series resonant circuit shown in FIG. 11, the capacitance value of the capacitor C becomes relatively large, and the resonance frequency fc of the resonance circuit moves to a low band.

  According to the equalizer 200 according to the second embodiment, the electrical length of the open-ended line 7 can be finely adjusted by changing the number of cuts of the plurality of inductors. Therefore, the amount of change in the resonance frequency can be set more finely than in the first embodiment, and the equalizer characteristics can be set with higher accuracy in accordance with the characteristics of the semiconductor components used in the high-frequency equipment. .

  The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

  1 main line, 2 ground, 3 resistance, 4 transmission line, 5 tip short circuit line, 6 series circuit, 7 tip open line, 7a one end, 7b other end, 8 inductor, 8a one end, 8b other end, 9 input terminal, 10 Output terminal, 11 series resonance circuit, 71 base end, 72 bent portion, 73 tip, 81 first inductor, 81a one end, 81b other end, 82 second inductor, 82a one end, 82b other end, 100, 200 equalizer.

Claims (2)

A series circuit that is provided between the main line through which a signal propagates and the ground, and is configured by connecting a resistor, a transmission line, and a short-circuited tip line in series;
One end is connected to the connection end of the transmission line and the tip short-circuited line, the other end side is bent at the tip open line,
One end is connected to the connection side of the transmission line, the tip short circuit line and the tip open line, the other end is connected to the other end side of the tip open line,
With
The electrical length from one end of the open end line to the other end of the open end line before the inductor is cut from the open end line is Φa, and the end after the inductor is cut from the open end line An equalizer characterized in that Φa <Φb, where Φb is the electrical length from one end of the open line to the other end of the open end line. Comprising a plurality of the inductors;
The first inductor of the plurality of inductors, one end is connected to the connection side of the transmission line, the tip short circuit line and the tip open line, the other end is connected to the other end side of the tip open line,
A second inductor of the plurality of inductors has one end connected in parallel to the first inductor and connected to the transmission line, the tip short-circuit line, and the tip open line, and the other end connected to the tip open line. Connected to the other end of
The electrical length before both the first inductor and the second inductor are cut is Φa1, and before the second inductor is cut from the open end line, and from the open end line, the first length is cut. 2, wherein the electrical length from one end of the open-ended line to the other end of the open-ended line after the inductor 1 is cut is Φa 2, wherein Φa 1 <Φa 2 <Φb. Equalizer.

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