JP4147827B2 - High frequency switch circuit and communication device using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a high-frequency switch circuit and communication equipment using the same, and more particularly to a technique for reducing insertion loss due to switch elements constituting the high-frequency switch circuit.
[0002]
[Prior art]
In a communication device for wireless communication or the like, a diversity system may be employed for fading countermeasures. In particular, some wireless communication devices employ a so-called spatial diversity reception system in which two antennas are arranged apart from each other by a predetermined distance and a signal received by each antenna is switched according to a reception state.
[0003]
To adopt such a diversity system, a total of four ports, two ports to which the main antenna and the diversity antenna are respectively connected, and two ports to which the transmission circuit and the reception circuit are respectively connected, are selected according to the transmission / reception state. It is necessary to switch and select each. Therefore, in the prior art, for example, a high frequency switch circuit having a configuration as shown in FIG. 9 is used.
[0004]
That is, the high-frequency switch circuit 51 includes a pair of upper and lower SPDT (single pole dual throw, single pole double throw type) switches 21 and 31. One SPDT switch 21 has two ports P1, P2, two through switch elements SW1, SW2, and two shunt switch elements SW5, SW6. Similarly, the other SPDT switch 31 has two ports P3 and P4, two through switch elements SW3 and SW4, and two shunt switch elements SW7 and SW8. The central ports (single poles) P0 of the SPDT switches 21 and 31 are connected to each other so as to be compatible with the diversity system.
[0005]
That is, for example, one SPDT switch 21 is arranged on the communication device side, and of the two ports P1 and P2, a transmission circuit is connected to one port P1 and a reception circuit is connected to the other port P2. Is done. The other SPDT switch 31 is arranged on the antenna side, and of the two ports P3 and P4, the main antenna is connected to the port P3 on one side, and the diversity antenna is connected to the port 4 on the other side. Since the high-frequency switch circuit 51 is vertically symmetric, one SPDT switch 21 may be disposed on the antenna side and the other SPDT switch 31 may be disposed on the communication device side, contrary to the above.
[0006]
Each of the through switch elements SW1 to SW4 is inserted in the middle of the signal line, and each of the through switch elements SW1 to SW4 is turned on / off according to the transmission / reception state, so that the ports P1 to P4 are selectively connected. Connected to. Each shunt switch element SW5 to SW8 is inserted between the signal line and the ground, and a high frequency signal may leak even when the through switch elements SW1 to SW4 are turned off. The shunt switch elements SW5 to SW8 are turned on in response to the turning off of SW4 to ensure isolation.
[0007]
In the high-frequency switch circuit 51 configured as described above, there are four types of ports that are actually connected according to the transmission / reception state: port P1 and port P3, port P1 and port P4, port P2 and port P3, and port 2 and port P4. Yes, the on / off states of the switch elements SW1 to SW8 are selected so that four connection states are obtained in this way.
[0008]
For example, when a signal from the transmission circuit is transmitted via the main antenna, it is necessary to connect the two ports P1 and P3. In this case, the through switch elements of SW1 and SW3 are turned on, SW2 and SW4. The through switch elements of SW5, SW7 are turned off, and the shunt switch elements of SW6, SW8 are turned on. As a result, the transmission signal input from the port P1 on one side is transmitted via the main antenna (not shown) connected to the port P3 on the other side through the through switch elements SW1 and SW3.
[0009]
FIG. 10 is a circuit diagram showing a configuration of a conventional high-frequency switch circuit compatible with a diversity system when field effect transistors (hereinafter referred to as FETs) are used as the switch elements SW1 to SW8.
[0010]
The basic configuration of the high-frequency switch circuit 52 is the same as that of the high-frequency switch circuit 51 shown in FIG. 9, but in the case of FIG. 10, since the switch elements SW1 to SW8 are FETs, the switch elements SW1 to SW8. Control terminals D1 to D8 are connected to the gates of the gates via resistors R1 to R8. Also, DC cut capacitors C1 to C4 having a sufficiently low impedance at a signal frequency to be driven by a single positive power supply are connected to the drains of the shunt switch elements SW5 to SW8, respectively, and are grounded at a high frequency. ing.
[0011]
In this configuration, for example, when two ports P1 and P3 are connected, a positive control voltage Vcol (for example, 3V) is applied to the control terminals D1 and D3, the through switch elements of SW1 and SW3 are turned on, and the control terminal D2 , D4 is applied with 0v to turn off the through switch elements of SW2 and SW4, 0v is applied to the control terminals D5 and D7 to turn off the shunt switch elements of SW5 and SW7, and the positive control voltage Vcol is applied to the control terminals D6 and D8. (For example, 3V) is applied, and the shunt switch elements SW6 and SW8 are turned on. Thereby, the port P1 on one side is connected to the port P3 on the other side through the through switch elements SW1 and SW3.
[0012]
[Problems to be solved by the invention]
By the way, in the high-frequency switch circuit as shown in FIGS. 9 and 10, when any port is connected via the switch element in the on state, the switch element in the on state acts as a resistance element. The switch element in the off state acts as a capacitive element.
[0013]
For example, when the two ports P1 and P3 are connected as described above, the through switch elements of SW1 and SW3 are on, the through switch elements of SW2 and SW4 are off, the shunt switch elements of SW5 and SW7 are off, SW6, The shunt switch element of SW8 is turned on, and this state is shown in FIG. 11 as an equivalent circuit. That is, the through switch elements SW1 and SW3 and the shunt switch elements SW6 and SW8 in the on state act as resistance elements, and the through switch elements SW2 and SW4 and the shunt switch elements SW5 and SW7 in the off state act as capacitive elements, respectively.
[0014]
Therefore, as can be seen from FIG. 11, the switch elements SW2, SW4, SW5, and SW7 in the off state exist as parasitic capacitances connected between the signal lines between the two ports P1 and P3 and the ground. This causes deterioration of the insertion loss of the signal line. In particular, when two SPDT switches 21, 31 (or 22, 32) are combined to support a diversity system, the number of switch elements inserted in the signal line increases, so that insertion loss is reduced. The effect of deterioration is increased.
[0015]
In addition, when each of the switch elements SW1 to SW8 is composed of an FET, if the gate width is increased in order to reduce the resistance value when the through switch elements SW1 to SW4 are turned on and act as resistance elements, conversely When these through switch elements SW1 to SW4 are turned off to function as capacitive elements, the capacitance value increases. As a result, for example, in the example shown in FIG. 11, when a signal is passed through the signal line between the two ports P1 and P3, the signal leakage of the through switch elements SW2 and SW4 that are turned off increases, resulting in an insertion loss. to degrade. These effects become more pronounced as the signal frequency increases.
[0016]
The present invention was devised in view of such inconveniences, and a high-frequency switch circuit compatible with a diversity system in which deterioration of insertion loss due to a switch element in a required frequency band is improved, and such a high-frequency switch circuit is provided. It is an object to provide an integrated communication device.
[0017]
[Means for Solving the Problems]
In order to solve the above problems, the present invention is as follows.
That is, the high-frequency switch circuit according to the first aspect of the present invention is a high-frequency switch circuit configured by connecting single poles of a pair of SPDT switches to each other. And a shunt switch element, and an inductor is interposed between the single poles of the pair of SPDT switches. The low-pass filter is configured using the capacitance value when the switch element is off and the inductance component of the inductor. It is characterized by that.
[0018]
By providing such an inductor, the switch element that is in the OFF state in the middle of the signal line functions as a low-pass filter depending on the relationship with the inductor from the conventional existence as a mere parasitic capacitance. And, by setting the inductance component of this inductor according to the magnitude of the capacitance value of the parasitic capacitance so that the cut-off frequency of this low-pass filter is larger than the required frequency band, Deterioration of insertion loss can be improved.
[0019]
A high-frequency switch circuit according to a second aspect of the invention is characterized in that, in the configuration of the first aspect of the invention, each switch element constituting the SPDT switch comprises a field effect transistor. As a result, the overall configuration of the high-frequency switch circuit is extremely miniaturized.
[0020]
A high-frequency switch circuit according to a third aspect of the invention is characterized in that, in the configuration of the second aspect of the invention, the field effect transistor is of a multi-gate type. As a result, high power can be turned on / off with a low operating voltage, and the overall configuration can be simplified as compared with a case where a plurality of field effect transistors are connected in multiple stages in series.
[0021]
According to a fourth aspect of the present invention, there is provided a high-frequency switch circuit according to the first aspect of the present invention, wherein each switch element constituting the SPDT switch is formed by sequentially connecting a plurality of field effect transistors in series. Yes. As a result, it is possible to turn on / off high power with a low operating voltage as compared with the case where each switch element is configured by a single field effect transistor.
[0022]
According to a fifth aspect of the present invention, there is provided a high frequency switch circuit according to the first to fourth aspects of the present invention, wherein a shunt provided between the signal line and the ground among the switch elements constituting the SPDT switch. The switch element is further characterized in that a series resonance circuit composed of an inductor and a capacitor is interposed between the switch element and the ground. Thereby, the isolation characteristic at the time of connecting between ports can be improved.
[0023]
A communication device according to a sixth aspect of the invention is characterized in that the high-frequency switch circuit according to any one of the first to fifth aspects is incorporated. In this way, it is possible to obtain a communication device having excellent characteristics with little insertion loss during signal transmission / reception.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
(Embodiment 1)
FIG. 1 is a circuit diagram showing a configuration of a high-frequency switch circuit according to Embodiment 1 of the present invention. Components corresponding to those of the prior art shown in FIG.
[0025]
The high-frequency switch circuit 11 according to the first embodiment is compatible with a diversity system and includes a pair of upper and lower SPDT switches 21 and 31. As a feature of the first embodiment, the single poles in the center of the SPDT switches 21 and 31 are connected to each other via an inductor L0.
[0026]
One SPDT switch 21 has two ports P1, P2, two through switch elements SW1, SW2, and two shunt switch elements SW5, SW6. Similarly, the other SPDT switch 31 has two ports P3 and P4, two through switch elements SW3 and SW4, and two shunt switch elements SW7 and SW8. One SPDT switch 21 is disposed on the communication device side, and the other SPDT switch 31 is disposed on the antenna side. On the contrary, one SPDT switch 21 may be arranged on the antenna side, and the other SPDT switch 31 may be arranged on the communication apparatus side.
[0027]
The role of each of the through switch elements SW1 to SW4 and the shunt switch elements SW5 to SW8 is the same as that of the conventional case shown in FIG. 9, and each switch element when the ports P1 to P4 are connected to each other. Since the setting of the on / off states of SW1 to SW8 is the same as in the conventional case, detailed description thereof is omitted here.
[0028]
Next, the operation of the inductor L0 interposed between the single poles of both SPDT switches 21 and 31 in the high-frequency switch circuit 11 shown in FIG. 1 will be described.
[0029]
For example, when the two ports P1 and P3 are connected as described above, the through switch elements of SW1 and SW3 are on, the through switch elements of SW2 and SW4 are off, the shunt switch elements of SW5 and SW7 are off, SW6, The shunt switch element of SW8 is turned on.
[0030]
At this time, the through switch elements SW1 and SW3 and the shunt switch elements SW6 and SW8 in the on state act as resistance elements, and the through switch elements SW2 and SW4 and the shunt switch elements SW5 and SW7 in the off state act as capacitive elements. When this state is shown by an equivalent circuit, it becomes as shown in FIG.
[0031]
Here, when the inductor L0 is provided between the single poles at the center of the SPDT switches 21 and 31 as in the first embodiment, the portion surrounded by the broken line in FIG. 2 acts as a low-pass filter. become. That is, the through switch elements SW2 and SW4 that are in the OFF state in the middle of the signal line play a role as an LC low-pass filter due to the relationship with the inductor L0 from the existence as a mere parasitic capacitance.
[0032]
Therefore, the inductance component of the inductor L0 is set according to the magnitude of the capacitance values of the two through switch elements SW2 and SW4 in the off state so that the cut-off frequency of the low-pass filter is larger than the required frequency band. By setting, it is possible to improve the degradation of insertion loss over a wide band up to a high frequency band.
[0033]
In the case where the equivalent circuit shown in FIG. 2 is configured in the high-frequency switch circuit 11 of the first embodiment, and in the case where the equivalent circuit shown in FIG. FIG. 3 shows a result obtained by simulating the relationship. Here, the inductance value of the inductor L0 is 1 nH, and the resistance value when the through switch elements SW1 to SW4 are turned on to act as resistance elements is 3Ω, and the through switch elements SW1 to SW4 are turned off and the capacitive element When the capacitance value is 0.3 pF, the shunt switch elements SW5 to SW8 are turned on to act as resistance elements, the resistance value is 6Ω, and the shunt switch elements SW5 to SW8 are turned off to act as capacitance elements Is set to 0.15 pF.
[0034]
As can be seen from FIG. 3, in the range where the frequency is 10 GHz or less, the insertion loss (shown by a solid line in FIG. 2) with respect to the frequency of the equivalent circuit shown in FIG. It can be understood that the rate of deterioration of the insertion loss is smaller than the insertion loss (shown by a broken line in the figure), and the deterioration of the insertion loss is improved over a wide band. Note that since there is a cut-off frequency as a low-pass filter around 15-20 GHz, the insertion loss deteriorates at higher frequencies, but there is no problem because it is outside the required frequency band.
[0035]
(Embodiment 2)
FIG. 4 is a circuit diagram showing the configuration of the high-frequency switch circuit according to Embodiment 2 of the present invention, and the same reference numerals are given to the components corresponding to those of the prior art shown in FIG.
[0036]
The basic configuration of the high-frequency switch circuit 12 in the second embodiment is the same as that of the high-frequency switch circuit 11 shown in FIG. 1, and includes a pair of upper and lower SPDT switches 22 and 32, each of the SPDT switches 22 and 32. Central single poles are connected to each other via an inductor L0.
[0037]
In the case of the high-frequency switch circuit 12 according to the second embodiment, FETs are used as the switch elements SW1 to SW8. Therefore, the control terminals are connected to the gates of the switch elements SW1 to SW8 via resistors R1 to R8. D1 to D8 are connected. Furthermore, DC-cut capacitors C1 to C4 having a sufficiently low impedance at a signal frequency to be driven by a single positive power source are individually connected to the drains of the shunt switch elements SW5 to SW8, respectively, and grounded at a high frequency. Has been.
[0038]
The functions of each of the through switch elements SW1 to SW4 and the shunt switch elements SW5 to SW8 are the same as those of the conventional case shown in FIG. 11, and each switch element when the ports P1 to P4 are connected to each other. Since the setting of the on / off states of SW1 to SW8 is the same as in the conventional case, detailed description thereof is omitted here.
[0039]
In the case where the equivalent circuit shown in FIG. 2 is configured in the high-frequency switch circuit 12 of the second embodiment, and in the case where the equivalent circuit shown in FIG. The result of examining the relationship is shown in FIG. Here, the inductance value of the inductor L0, the resistance value when the switch elements SW1 to SW8 are turned on, and the capacitance value when the switch elements are turned off are set to the same values as in the first embodiment.
[0040]
As can be seen from FIG. 5, even in the case of the second embodiment, the insertion loss (shown by a solid line in the figure) with respect to the frequency of the equivalent circuit shown in FIG. It can be understood that the ratio of deterioration of the insertion loss is smaller than the insertion loss with respect to the frequency of the conventional equivalent circuit (indicated by a broken line in the figure), and the deterioration of the insertion loss is improved over a wide band.
[0041]
(Embodiment 3)
FIG. 6 is a circuit diagram showing the configuration of the high-frequency switch circuit according to the third embodiment of the present invention. Components corresponding to those of the high-frequency switch circuit according to the second embodiment shown in FIG. .
[0042]
The basic configuration of the high-frequency switch circuit 13 of the third embodiment is the same as that of the high-frequency switch circuit 12 shown in FIG. 4, and includes a pair of upper and lower SPDT switches 23 and 33. Central single poles are connected to each other via an inductor L0.
[0043]
In addition, capacitors C6 to C9 and inductors L1 to L4 are connected in series to the drains of the shunt switch elements SW5 to SW8 to form series resonance circuits 41 to 44. In this case, the inductors L1 to L4 may use a dedicated wire, a bonding wire having an inductance component, a package lead, or the like.
Since the other configuration is the same as that of the second embodiment shown in FIG. 4, detailed description thereof is omitted here.
[0044]
Here, if the capacitance value and the inductance value are set so that the series resonance circuits 41 to 44 including the capacitors C6 to C9 and the inductors L1 to L4 are in series resonance at a desired frequency, the shunt switch elements SW5 to SW8 are turned on. In this case, it is possible to reduce the impedance when the shunt switch elements SW5 to SW8 are viewed from the signal line. For this reason, when the ports P1 to P4 are connected to each other, it is possible to improve the isolation characteristics so that no extra signal leakage occurs. For example, in order to resonate each series resonance circuit 41 to 44 at 5 GHz, the capacitance values of the capacitors C6 to C9 may be 1 pF, and the inductance values of the inductors L1 to L4 may be 1 nH.
[0045]
(Embodiment 4)
FIG. 7 is a circuit diagram showing the configuration of the high-frequency switch circuit according to the fourth embodiment of the present invention, and components corresponding to those of the high-frequency switch circuit according to the third embodiment shown in FIG. .
[0046]
The basic configuration of the high-frequency switch circuit 14 of the fourth embodiment is the same as that of the high-frequency switch circuit 13 shown in FIG. 6, and includes a pair of upper and lower SPDT switches 24 and 34. Central single poles are connected to each other via an inductor L0.
[0047]
Further, in the third embodiment shown in FIG. 6, the series resonant circuits 41 to 44 including capacitors C1 to C4 and inductors L1 to L4 are individually connected to the shunt switch elements SW5 to SW8 including FETs. However, in the fourth embodiment, the drains of the shunt switch elements SW5 to SW8 are connected in common and then grounded via one series resonance circuit 45 including the capacitor C5 and the inductor L5. With such a configuration, since the number of capacitors and inductors can be reduced, the chip size can be reduced and the number of package terminals can be reduced.
Since other configurations and operations are the same as those of the third embodiment shown in FIG. 6, detailed description thereof is omitted here.
[0048]
The following modifications and application examples can be further considered for the above-described first to fourth embodiments.
[0049]
(1) In the first to fourth embodiments described above, the inductor L0 interposed between the single poles at the center of the pair of SPDT switches uses a dedicated element, but instead, a bonding having an inductor component is used. It is also possible to use wires and package leads.
[0050]
{Circle around (2)} In the above first to fourth embodiments, the high-frequency switch circuits 11 to 14 are assumed to be formed as one chip as a whole, but the present invention is not limited to this, and the SPDT switches 21 and 31 are not limited thereto. , 22 and 32, 23 and 33, and 24 and 34 are manufactured in advance as separate chips, and the single port of each chip is connected with a wire serving as an inductor L0 to constitute the high-frequency switch circuit of the present invention. .
[0051]
(3) In the above second to fourth embodiments, the control terminals D1 to D8 for turning on / off the switching elements SW1 to SW8 made of FETs are individually provided. The control terminals D5, D3 and D8, and D4 and D7 are connected in common so that the switch elements SW1 and SW6, SW2 and SW5, SW3 and SW8, and SW4 and SW7 are turned on / off in conjunction with each other. You can also In this case, the number of control terminals can be reduced.
[0052]
(4) In the above-described Embodiments 2 to 4, a single gate type FET is used as the FET, but a multi-gate type FET can also be used. If such a multi-gate FET is used, high power can be turned on / off at a lower operating voltage than that of a single gate type, and the overall configuration is simpler than that of a multi-stage connection of multiple FETs. Can be
[0053]
(5) In the above-described Embodiments 2 to 4, each switch element SW1 to SW8 is composed of a single FET, but each switch element SW1 to SW8 connects a plurality of FETs sequentially in series. It can also be configured. Such a multi-stage configuration provides an advantage that high power can be turned on / off with a low operating voltage, as compared with the case where each switch element SW1 to SW8 is configured with a single FET.
[0054]
(6) In a communication device such as a portable wireless device, as shown in FIG. 8, the high-frequency switch circuits 11 to 14 of the above-described embodiments are mounted on a wiring board 61 as a chip, and this is mounted in a case 62. It can also be stored and used. In this way, it is possible to obtain a communication device having excellent characteristics with little insertion loss when transmitting and receiving signals.
[0055]
【The invention's effect】
In the high-frequency switch circuit according to the first aspect of the present invention, the single poles of the pair of SPDT switches are connected to each other via an inductor. Since it exists as a parasitic capacitance, it acts as a low-pass filter depending on the relationship with the inductor. And, by setting the inductance component of this inductor according to the magnitude of the capacitance value of the parasitic capacitance so that the cut-off frequency of this low-pass filter is larger than the required frequency band, Deterioration of insertion loss can be improved.
[0056]
In the high frequency switch circuit according to the second aspect of the invention, in addition to the effect of the first aspect of the invention, each switch element constituting the SPDT switch is composed of a field effect transistor. Miniaturized.
[0057]
In addition to the effect of the invention of claim 2, the high-frequency switch circuit according to the invention of claim 3 is a multi-gate type field effect transistor, so that high power can be turned on / off with a low operating voltage, In addition, the overall configuration can be simplified as compared to a case where a plurality of field effect transistors are connected in series in multiple stages.
[0058]
The high-frequency switch circuit according to the invention described in claim 4 has, in addition to the effect of the invention described in claim 1, each switch element constituting the SPDT switch is formed by sequentially connecting a plurality of field effect transistors in series. Compared with the case where the switch element is configured by a single field effect transistor, high power can be turned on / off with a low operating voltage.
[0059]
The high-frequency switch circuit according to the invention of the fifth aspect is provided between the signal line and the ground among the switch elements constituting the SPDT switch in addition to the effects of the inventions of the first to fourth aspects. The shunt switch element further includes a series resonance circuit composed of an inductor and a capacitor between the switch and ground, so that signal leakage does not occur when the ports are connected via the switch element. In addition, the isolation characteristics can be improved.
[0060]
Since the communication device according to the invention of claim 6 is constructed by incorporating the high-frequency switch circuit according to any one of claims 1 to 5, it has excellent characteristics with low insertion loss when transmitting and receiving signals. Communication equipment with it.
[Brief description of the drawings]
FIG. 1 is a circuit diagram showing a configuration of a high-frequency switch circuit according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of an equivalent circuit obtained when a switch element is turned on / off and ports are connected in the high-frequency switch circuit according to the first embodiment of the present invention.
FIG. 3 is a characteristic diagram showing the result of simulating the effect of insertion loss in the high frequency switch circuit of FIG. 1 in comparison with the case of a conventional high frequency switch circuit.
FIG. 4 is a circuit diagram showing a configuration of a high-frequency switch circuit according to a second embodiment of the present invention.
5 is a characteristic diagram showing the result of simulating the effect of insertion loss in the high frequency switch circuit of FIG. 4 in comparison with the case of a conventional high frequency switch circuit.
FIG. 6 is a circuit diagram showing a configuration of a high-frequency switch circuit according to a third embodiment of the present invention.
FIG. 7 is a circuit diagram showing a configuration of a high frequency switch circuit according to a fourth embodiment of the present invention.
FIG. 8 is a perspective view showing a cellular phone device incorporating the high-frequency switch circuit of the present invention.
FIG. 9 is a circuit diagram showing a configuration of a conventional high-frequency switch circuit.
FIG. 10 is a circuit diagram showing a configuration of a conventional high-frequency switch circuit using a field effect transistor as a switch element.
FIG. 11 is a diagram illustrating an example of an equivalent circuit obtained when a switch element is turned on / off and ports are connected in a conventional high-frequency switch circuit.
[Explanation of symbols]
11-14 High frequency switch circuit
21-24 SPDT switch
31-34 SPDT switch
41-45 series resonant circuit
P1 to P4 ports
SW1 to SW4 Through switch element
SW5 to SW8 Shunt switch element
R1-R8 resistance
C1-C9 capacitors
L0, L1-L5 inductor
D1-D8 control terminal

Claims (6)

In a high frequency switch circuit configured by connecting single poles of a pair of SPDT switches to each other,
Each of the pair of SPDT switches includes a through switch element and a shunt switch element between the terminals, an inductor is interposed between the single poles of the pair of SPDT switches, and the switch element A high-frequency switch circuit comprising a low-pass filter using a capacitance value in an off state and an inductance component of the inductor .   2. The high-frequency switch circuit according to claim 1, wherein each switch element constituting the SPDT switch comprises a field effect transistor.   3. The high frequency switch circuit according to claim 2, wherein the field effect transistor is of a multi-gate type.   2. The high-frequency switch circuit according to claim 1, wherein each switch element constituting the SPDT switch is formed by sequentially connecting a plurality of field effect transistors in series.   Among the switch elements constituting the SPDT switch, a shunt switch element provided between the signal line and the ground further includes a series resonance circuit including an inductor and a capacitor between the ground. The high-frequency switch circuit according to claim 1, wherein the high-frequency switch circuit is provided.   A communication apparatus comprising the high-frequency switch circuit according to any one of claims 1 to 5.

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