KR20170018773A - Switch module, front-end module, and driving method for switch module - Google Patents

Abstract

The present invention provides a switch module capable of reducing a transmission loss of a signal in a system capable of selecting a carrier aggregation (CA) mode and a non-CA mode. According to the present invention, the switch module (10) comprises: a switch circuit (20); and a variable adjustment unit (25). The switch circuit (20) may select the CA mode simultaneously using first and second frequency bands, and the non-CA mode using only the first frequency band or the second frequency band, and switches connection between an antenna device (2) and any one of a first signal path (23M) for transmitting the first frequency band, a second signal path (23H) for transmitting the second frequency band, and a third signal path (23B) simultaneously transmitting signals of the first and second frequency bands. The variable adjustment unit (25) adjusts a variable matching circuit of the third signal path (23B) when the non-CA mode is selected, or adjusts a variable matching circuit of the first signal path (23M) or the second path (23H) when the CA mode is selected.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a switch module, a front end module,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch module, a front end module, and a driving method of a switch module used for wireless communication.

In order to cope with the improvement of the international roaming and the communication speed, the cellular phone is required to correspond to a plurality of frequency and radio systems in one terminal (multiband and multi mode).

Patent Document 1 discloses a switch of a single input n-output type sPnT (Single Pole Throw) which connects one common terminal and two or more selection terminals at the same time, a variable impedance adjusting circuit connected to the subsequent stage, Discloses a front end circuit corresponding to a carrier aggregation (CA) including a duplexer to be connected. According to the above configuration, even when different frequency bands are used at the same time, signal leakage to other circuits can be prevented.

Japanese Patent Application Laid-Open No. 2014-17750

However, in order to cope with all communication environments in multi-banding and multimodeling, it is necessary to consider not only CA mode but also communication quality of a so-called non-CA mode in which a single-band or a single mode is used as communication. In the front end circuit described in Patent Document 1, the impedance is adjusted between the two frequency bands simultaneously operating in the CA mode, and the impedance adjustment in the non-CA mode is not mentioned. That is, the impedance adjustment of the signal path for the non-CA mode when operating in the CA mode and the impedance adjustment of the signal path for the CA mode when operating in the non-CA mode are not performed. Particularly, in the CA-compatible front-end circuit, since a plurality of signal paths are connected to the switches when operating in the CA mode, impedance mismatching is likely to occur due to parasitic components in the switches. Therefore, there is a problem that the signal loss is increased and the pass characteristic is deteriorated.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above problems, and provides a method of driving a switch module, a front-end module, and a switch module capable of reducing signal propagation loss in a system capable of selecting a CA mode and a non- .

In order to accomplish the above object, a switch module according to an embodiment of the present invention includes a carrier signal which simultaneously uses a first frequency band for radio communication and a second frequency band for radio communication different in frequency band from the first frequency band (CA) mode and a non-CA mode using only one of the first frequency band and the second frequency band, the switch module comprising: a first signal path for propagating a signal in the first frequency band; A second signal path for propagating the signal of the second frequency band, a third signal path for simultaneously propagating the signal of the first frequency band and the signal of the second frequency band, a common signal terminal connected to the antenna element, A first selection terminal connected to one end of the first signal path, a second selection terminal connected to one end of the second signal path, And a switch circuit for exclusively switching the connection between the common terminal and any one of the first selection terminal, the second selection terminal and the third selection terminal, Wherein the switch circuit includes a first variable matching circuit disposed between the first selection terminal and the ground terminal, a second variable matching circuit disposed between the second selection terminal and the ground terminal, and a second variable matching circuit disposed between the third selection terminal and the ground terminal And wherein the switch module adjusts the third variable matching circuit when the non-CA mode is selected, or adjusts the third variable matching circuit when the CA mode is selected, And a variable adjuster for variably adjusting at least one of the first variable matching circuit and the second variable matching circuit.

According to this configuration, in the configuration having separate signal paths in the CA mode and the non-CA mode, the variable adjustment section not only adjusts the impedance of the signal path used for wireless communication, but also adjusts the impedance of the signal path not used for wireless communication Adjust. Therefore, it is possible to improve the isolation between the signal path used in the wireless communication and the signal path not used, and to suppress the impedance mismatch in the signal path used for the wireless communication.

It is preferable that the variable adjusting section adjusts the impedance of the third variable matching circuit when the first frequency band is selected among the non-CA modes and the impedance of the third variable matching circuit when the second frequency band is selected among the non- The impedance of the third variable matching circuit may be different.

Thus, even when the non-CA mode is selected, the impedance of the signal path used in the CA mode is different if the selected frequency band is different. Therefore, it is possible to adjust the impedance matching particularly in the non-CA mode with high accuracy according to the selected frequency band.

The switch circuit includes a first switch element for switching conduction and non-conduction between the first selection terminal and the common terminal, and a second switch element for switching conduction and non-conduction between the second selection terminal and the common terminal, And a third switch element for switching between conduction and non-conduction between the third selection terminal and the common terminal, wherein the third variable matching circuit switches conduction and non-conduction between the third selection terminal and the ground terminal Wherein the third shunt switch element makes the third shunt switch element nonconductive when the first frequency band is selected in the non-CA mode, and the third shunt switch element changes the second frequency band The third shunt switch element may be in the conduction state.

The second frequency band may be a frequency band allocated to a higher frequency side than the first frequency band.

As a result, when the second frequency band is selected among the non-CA modes, the third signal path is shunted by the third shunt switch element, so that one end of the third signal path is short-circuited. On the other hand, when the first frequency band is selected among the non-CA modes, since the third shunt switch element is in the non-conduction state, one end of the third signal path is in the open state. As a result, the impedance of the third signal path which is not used is adjusted according to the pass band of the signal being used, thereby improving the isolation between the third signal path and the first signal path used for wireless communication, The impedance mismatching of the second signal path can be suppressed.

The third signal path has a first path for selectively passing the first frequency band and a second path for selectively passing the second frequency band, and one end of the third signal path is connected to the first path A fourth switch element for switching between conduction and non-conduction between the one end of the first path and one end of the second path, and the other end of the first path and the first signal path; And a fifth switch element for switching conduction and non-conduction of the second signal path when the first frequency band is selected in the non-CA mode, wherein the variable adjusting section sets the fourth switch element to the non-conduction state , And when the second frequency band is selected among the non-CA modes, the fifth switch element may be in a non-conductive state.

As a result, when the first frequency band is selected among the non-CA modes, the first path of the third signal path becomes the load impedance through the fourth switch element which becomes capacitive with respect to the first signal path. When the second frequency band is selected among the non-CA modes, the second path of the third signal path becomes the load impedance through the fifth switch element which becomes capacitive with respect to the second signal path. In this case, since the impedance of the third signal path which is not used in accordance with the pass band of the signal being used is adjusted, the isolation between the third signal paths is improved, and the first signal path And the impedance mismatch of the second signal path can be highly suppressed.

An embodiment of the present invention may be a front end module including a switch module having the above-described characteristic configuration and a duplexer element connected to the other end of the first signal path or the other end of the second signal path.

Further, a power amplifier element connected to the transmission-side terminal of the duplexer element may be provided.

Further, a low-noise amplifier element connected to the reception-side terminal of the duplexer element may be provided.

As a result, it is possible to provide a front-end module capable of reducing signal propagation loss in a system capable of selecting a CA mode and a non-CA mode.

In addition, an embodiment of the present invention may be a switch module or a front end module having the above-described characteristic configuration, as well as a method of driving the switch module with the above-described characteristic configuration as a step.

This makes it possible to reduce signal propagation loss in a switch module capable of selecting the CA mode and the non-CA mode.

(Effects of the Invention)

According to the switch module of the present invention, it is possible to reduce the signal propagation loss in a system that can select the CA mode and the non-CA mode.

1 is a circuit diagram of a front end module and a peripheral circuit according to the embodiment.
2A is a circuit state diagram when the CA mode is selected in the switch module according to the embodiment.
FIG. 2B is a circuit state diagram when a non-CA mode (middle band) is selected in the switch module according to the embodiment.
2C is a circuit state diagram when a non-CA mode (high band) is selected in the switch module according to the embodiment.
3A is a circuit configuration diagram of a switch circuit according to the embodiment.
3B is a circuit configuration diagram of the CA switch circuit according to the embodiment.
3C is a circuit configuration diagram of the CA switch circuit according to the embodiment.
4 is a diagram showing a circuit state and an equivalent circuit when a non-CA mode (middle band) is selected in the switch module according to the embodiment.
5 is a diagram showing a circuit state and an equivalent circuit when a non-CA mode (high band) is selected in the switch module according to the embodiment.
6A is a Smith chart showing an impedance state when the third selection terminal is viewed from the third signal path when the non-CA mode (middle band) is selected.
6B is a Smith chart showing the impedance state when the third selection terminal is viewed from the third signal path when the non-CA mode (high band) is selected.
7A is a diagram showing the passing characteristic of the first signal path when the non-CA mode (middle band) is selected and the third shunt switch element is in the conduction state.
FIG. 7B is a diagram showing the passing characteristics of the first signal path when the non-conductive state of the third shunt switch element is selected by the non-CA mode (middle band).
8A is a diagram showing the passing characteristic of the second signal path when the non-CA mode (high band) is selected and the third shunt switch element is in the conduction state.
8B is a diagram showing the passing characteristics of the second signal path when the non-conductive state of the third shunt switch element is selected by the non-CA mode (high band).
9 is a circuit configuration diagram of a switch circuit according to a modification of the embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to embodiments and drawings. Further, the embodiments described below are all inclusive or specific examples. The numerical values, shapes, materials, constituent elements, arrangement and connection forms of the constituent elements and the like shown in the following embodiments are merely examples, and the present invention is not limited to these. The constituent elements in the following embodiments will be described as arbitrary constituent elements that are not described in the independent claims. In addition, the ratio of the size or size of the constituent elements shown in the drawings is not necessarily strict.

(Embodiments)

[One. 1 Front End Module Circuit Configuration]

1 is a circuit configuration diagram of a front end module 1 and a peripheral circuit according to the embodiment. The drawing shows a front end module 1, an antenna element 2, and an RF signal processing circuit (RFIC) 3 according to the first embodiment. The front end module 1, the antenna element 2, and the RF signal processing circuit 3 are disposed, for example, in a front end portion of a cellular phone compatible with multimode / multiband.

The front end module 1 includes a low pass filter 11, a switch module 10, duplexers 12M and 12H, low noise amplifiers 13M and 13H and power amplifiers 14M and 14H.

With the above configuration, the front end module 1 functions as a high-frequency front end circuit for wireless communication capable of alternatively selecting a carrier aggregation (CA) mode and a non-CA mode.

[One. 2 Circuit configuration of switch module]

The switch module (10) is a high-frequency switch module for switching the connection between the antenna element (2) and a signal path for propagating a signal of at least one frequency band selected from a plurality of frequency bands. In the switch module 10, a plurality of signal paths for transmitting and receiving radio signals with a plurality of frequency bands as carrier waves are formed so as to correspond to multimode / multiband. The switch module 10 includes a switch circuit 20, a first signal path 23M, a second signal path 23H, a third signal path 23B, a low-pass filter 21M, A filter 21H, CA switch circuits 22M and 22H, and a variable adjustment section 25. [

The first signal path 23M selectively propagates a frequency division duplex (FDD) signal in the first frequency band. The first frequency band is, for example, Band 4 (transmission band: 1710-1755 MHz, reception band: 2110-2155 MHz) of the LTE standard.

The second signal path 23H selectively propagates the FDD signal of the second frequency band that is higher in frequency than the first frequency band. The second frequency band is, for example, Band 7 (transmission band: 2500-2570 MHz, reception band: 2620-2690 MHz) of the LTE standard.

The third signal path 23B simultaneously propagates the FDD signal of the first frequency band and the FDD signal of the second frequency band. The third signal path 23B has a first path 23B1 for selectively propagating the FDD signal in the first frequency band and a second path 23B2 for selectively propagating the FDD signal in the second frequency band. Pass filter 21M and a CA switch circuit 22M are disposed in the first path 23B1 and a high pass filter 21H and a CA switch circuit 22H are disposed in the second path 23B2.

The signal for propagating the first signal path 23M, the second signal path 23H, and the third signal path 23B is not limited to the FDD method but may be another divided duplex method. In this case, the duplexers 12M and 12H connected to the first signal path 23M and the second signal path 23H may be a high-frequency switch or the like.

The switch circuit 20 includes a common terminal 20c connected to the antenna element 2 through the low-pass filter 11, a first selection terminal 20s1 connected to one end of the first signal path 23M, A second selection terminal 20s2 connected to one end of the signal path 23H and a third selection terminal 20s3 connected to one end of the third signal path 23B. The switch circuit 20 selectively switches the connection between the common terminal 20c and any one of the first selection terminal 20s1, the second selection terminal 20s2 and the third selection terminal 20s3, ) And one of the first signal path 23M, the second signal path 23H and the third signal path 23B.

The third selection terminal 20s3 is connected to one end of the first path 23B1 and the second path 23B2 is connected to one end of the third signal path 23B, As shown in Fig. The other end of the first path 23B1 is connected to the first signal path 23M through the CA switch circuit 22M. The other end of the second path 23B2 is connected to the second signal path 23H through the CA switch circuit 22H.

The variable adjustment unit 25 is a control unit for adjusting the circuit states of the switch circuit 20, the CA switch circuit 22M, and the CA switch circuit 22H based on the selection information of the CA mode and the non-CA mode. The variable adjustment section 25 can acquire the selection information from the RF signal processing circuit 3 or the switch circuit 20 subsequent to the front end module 1, for example. The operation of the variable adjustment unit 25 will be described later.

Here, in the front end module 1 according to the present embodiment, a so-called carrier aggregation (CA) method in which different frequency bands are simultaneously used for the purpose of improving communication quality is employed. However, in the system in which the CA system is adopted, a non-CA mode in which only one frequency band is selected and used in accordance with radio wave use conditions and a CA mode in which other frequency bands are used at the same time is set.

2A is a circuit state diagram when the CA mode is selected in the switch module 10 according to the embodiment. The third signal path 23B is connected to the antenna element 2 by the switch circuit 20 when the CA mode is selected in the switch module 10 according to the present embodiment. On the other hand, the first signal path 23M and the second signal path 23H are disconnected from the antenna element 2. By this connection mode, in the CA mode, the signal of the first frequency band propagates through the first path 23B1, and at the same time, the signal of the second frequency band propagates through the second path 23B2.

2B is a circuit state diagram when the first frequency band (middle band) of the non-CA mode is selected in the switch module 10 according to the embodiment. As shown in the figure, when the non-CA mode (middle band) is selected in the switch module 10 according to the present embodiment, the first signal path 23M is connected to the antenna element 2 by the switch circuit 20 do. On the other hand, the second signal path 23H and the third signal path 23B are disconnected from the antenna element 2. According to this connection mode, in the non-CA mode (middle band), the signal of the first frequency band propagates through the first signal path 23M.

2C is a circuit state diagram when the second frequency band (high band) of the non-CA mode is selected in the switch module 10 according to the embodiment. As shown in the figure, when the non-CA mode (high band) is selected in the switch module 10 according to the present embodiment, the second signal path 23H is connected to the antenna element 2 by the switch circuit 20, Respectively. On the other hand, the first signal path 23M and the third signal path 23B are disconnected from the antenna element 2. According to this connection mode, in the non-CA mode (high band), the signal of the second frequency band propagates through the second signal path 23H.

[One. 3 Circuit Configuration of Switch Element]

Here, the circuit configuration of the switch circuit 20 and the CA switch circuits 22M and 22H according to the present embodiment will be described.

3A is a circuit configuration diagram of the switch circuit 20 according to the embodiment. As shown in the figure, the switch circuit 20 is composed of six FETs (Field Effect Transistors) 201M, 201B, 201H, 202M, 202B and 202H. Each of the FETs is turned on or off between the source and the drain by a control signal supplied to the gate.

Further, the variable adjustment unit 25 adjusts the circuit state of the switch circuit 20 by supplying control signals to the gates of the six FETs.

The FETs 201M and 202M are switch elements that change the connection state of the first signal path 23M and the antenna element 2. [ The FET 202M is a first switch element for switching between conduction and non-conduction between the common terminal 20c and the first selection terminal 20s1 and the FET 202M is a conduction path between the first selection terminal 20s1 and the ground terminal, And is a first shunt switch element for switching non-conduction.

FETs 201H and 202H are switch elements that change the connection state of the second signal path 23H and the antenna element 2. [ The FET 201H is a second switch element for switching between conduction and non-conduction between the common terminal 20c and the second selection terminal 20s2 and the FET 202H is connected between the second selection terminal 20s2 and the ground terminal, And is a second shunt switch element for switching non-conduction.

FETs 201B and 202B are switch elements that change the connection state of the third signal path 23B and the antenna element 2. [ The FET 201B is a third switch element for switching between conduction and non-conduction between the common terminal 20c and the third selection terminal 20s3 and the FET 202B is a conduction path between the third selection terminal 20s3 and the ground terminal, And is a third shunt switch element for switching non-conduction.

The first switch element, the second switch element, and the third switch element are series-connected in series between the common terminal and the first selection terminal, the second selection terminal and the third selection terminal, respectively.

When the common terminal 20c and the first selection terminal 20s1 are connected to each other, that is, when the first signal path 23M in the non-CA mode is selected in the above configuration of the switch circuit 20, The FET 202M is turned off. Further, the FETs 201B and 201H are turned off. Therefore, when viewed from the common terminal 20c, the second signal path and the third signal path are in an open state. Thereby, the isolation between the common terminal 20c and the second selection terminal 20s2 and the isolation between the common terminal 20c and the third selection terminal 20s3 are secured at a predetermined level. When the common terminal 20c and the second selection terminal 20s2 are connected and the common terminal 20c and the third selection terminal 20s3 are connected to each other, the conduction state of the FET is set in the same manner as described above .

3B is a circuit configuration diagram of the CA switch circuit 22M according to the embodiment. As shown in the figure, the CA switch circuit 22M is constituted by an FET 221M. The FET 221M is transitioned between the source and the drain in a conduction state or a non-conduction state by a control signal supplied to the gate. The CA switch circuit 22M is disposed in the first path 23B1 of the third signal path 23B selected in the CA mode and is connected to the other end of the first path 23B1, And is a fourth switch element for switching conduction.

3C is a circuit configuration diagram of the CA switch circuit 22H according to the embodiment. As shown in the figure, the CA switch circuit 22H is constituted by an FET 221H. The FET 221H is turned on or off between the source and the drain by a control signal supplied to the gate. The CA switch circuit 22H is disposed in the second path 23B2 of the third signal path 23B selected in the CA mode and is electrically connected to the other end of the second path 23B2 and the second signal path 23H, And is a fifth switch element for switching conduction.

The variable adjustment section 25 also adjusts the circuit states of the CA switch circuit 22M and the CA switch circuit 22H by supplying control signals to the gates of the FET 221M and the FET 221H.

Hereinafter, the transition of the circuit state of the switch module 10 having the above-described configuration will be described in detail.

[One. 4 Circuit status of the switch module when the CA mode (middle band) is selected]

4 is a diagram showing a circuit state and an equivalent circuit when a non-CA mode (middle band) is selected in the switch module according to the embodiment. In addition, in the circuit shown in Fig. 4, the display of the variable adjusting section 25, the second path 23B2, and the second signal path 23H is omitted.

(Middle band) is selected as shown in the upper part of FIG. 4, the variable adjusting unit 25 (not shown) turns the FET 201M of the switch circuit 20 ON 202M to a non-conductive state (OFF). Thereby, the antenna element 2 and the first signal path 23M are connected. The variable adjustment unit 25 turns off the FET 201B of the switch circuit 20 and turns off the FET 202B. Thereby, the antenna element 2 and the third signal path 23B are disconnected. Further, the variable adjustment unit 25 turns the CA switch circuit 22M to the non-conductive state (OFF). As a result, the first signal path 23M and the first path 23B1 are disconnected. Further, the variable adjustment unit 25 turns off the FET 201H (OFF) (not shown). Thereby, the antenna element 2 and the second signal path 23H are disconnected.

4 shows an equivalent circuit when a non-CA mode (middle band) is selected. The third signal path 23B and the first signal path 23M are dynamically disconnected because the FET 201B and the FET 221M are in a non-conductive state. However, since the FET 201B and the FET 221M in the non-conduction state are regarded as capacitors as an equivalent circuit, the third signal path 23B and the first signal path 23M are connected via capacitors in a high frequency state . In this case, the signal passing characteristic of the first frequency band in the first signal path 23M is influenced by the impedance of the third signal path 23B connected through the FET 221M.

6A is a Smith chart showing the impedance state when the third selection terminal 20s3 is viewed from the third signal path 23B when the non-CA mode (middle band) is selected. As shown in the figure, when the non-conductive mode (middle band) is selected, since the FET 201B and the FET 202B are in a non-conductive state, the third selection terminal 20s3 from the third signal path 23B The impedance in the first frequency band is close to (infinite) (open).

FIG. 7A is a diagram showing the passing characteristic of the first signal path 23M when the non-CA mode (middle band) is selected and the FET 202B is in the conduction state. 7B is a diagram showing the passing characteristic of the first signal path 23M when the non-conductive state of the FET 202B is selected by the non-CA mode (middle band). The vertical axis shown in Figs. 7A and 7B indicates the insertion in the first signal path 23M from the connection terminal of the antenna element 2 and the low-pass filter 11 to the other end of the first signal path 23M. Respectively.

In Fig. 7A, when the FET 202B is in the conduction state, a notch that deteriorates the insertion loss in the first frequency band (around 2 GHz) is observed. On the other hand, when the FET 202B is in the non-conduction state as shown in Fig. 7B, the notch disappears in the first frequency band (around 2 GHz). That is, when the non-CA mode (middle band) is selected, the transmission characteristic of the first frequency band (middle band) in the first signal path 23M is made positive by turning off the FET 202B.

[One. 5 Circuit status of switch module when CA mode (high band) is selected]

5 is a diagram showing circuit states and equivalent circuits when a non-CA mode (high band) is selected in the switch module according to the embodiment. In addition, in the circuit shown in Fig. 5, the display of the variable adjustment section 25, the first path 23B1, and the first signal path 23M is omitted.

5, when the non-CA mode (high band) is selected, the variable adjustment unit 25 (not shown) turns the FET 201H of the switch circuit 20 into the conduction state (ON) 202H to the non-conductive state (OFF). Thereby, the antenna element 2 and the second signal path 23H are connected. The variable adjustment unit 25 also sets the FET 201B of the switch circuit 20 to the non-conductive state (OFF) and the FET 202B to the conductive state (ON). Thereby, the antenna element 2 and the third signal path 23B are disconnected. In addition, the variable adjusting unit 25 sets the CA switch circuit 22H to the non-conductive state (OFF). As a result, the second signal path 23H and the second path 23B2 are disconnected. Further, the variable adjusting unit 25 turns off the FET 201M (OFF) (not shown). Thereby, the antenna element 2 and the first signal path 23M are disconnected.

5 shows an equivalent circuit when a non-CA mode (middle band) is selected. The third signal path 23B and the second signal path 23H are disconnected in a DC state because the FET 201B and the FET 221H are in a non-conductive state. However, since the FETs 201B and 221H in the non-conduction state are regarded as capacitors as equivalent circuits, the third signal path 23B and the second signal path 23H are connected via capacitors in a high frequency state . In this case, the signal passing characteristic of the second frequency band in the second signal path 23H is influenced by the impedance of the third signal path 23B connected via the FET 221H.

6B is a Smith chart showing the impedance state when the third selection terminal 20s3 is viewed from the third signal path 23B when the non-CA mode (high band) is selected. As shown in the figure, when the non-CA mode (high band) is selected, the FET 201B is in the non-conductive state and the FET 202B is in the conductive state. The impedance in the second frequency band is close to 0 (short).

8A is a diagram showing the passing characteristic of the second signal path 23H when the non-CA mode (high band) is selected and the FET 202B is in the conduction state. 8B is a diagram showing the passing characteristic of the second signal path 23H when the non-conductive state of the FET 202B is selected by the non-CA mode (high band). The vertical axis shown in Figs. 8A and 8B indicates the insertion in the second signal path 23H from the connection terminal of the antenna element 2 and the low-pass filter 11 to the other end of the second signal path 23H. Respectively.

In FIG. 8B, when the FET 202B is in the non-conductive state, a notch that deteriorates the insertion loss is observed in the second frequency band (around 2.7 GHz). In contrast, when the FET 202B is in the conduction state as shown in Fig. 8A, the notch disappears in the second frequency band (around 2.7 GHz). That is, when the non-CA mode (high band) is selected, the transmission characteristic of the second frequency band (high band) in the second signal path 23H is increased by making the FET 202B conductive.

[One. Switching of six variable adjustment parts]

The transmission characteristic of the first frequency band in the first signal path 23M at the time of selecting the above-mentioned non-CA mode (middle band) and the transmission characteristic at the time of the second signal path 23H at the time of selecting the non- From the pass characteristic of the second frequency band, the variable adjustment section 25 switches the FET 202B connected to one end of the third signal path 23B, which is not selected when the non-CA mode (middle band) is selected, . On the other hand, when the non-CA mode (high band) is selected, the FET 202B connected to the third signal path 23B which is not selected is made conductive. That is, even if the non-CA mode is selected, the circuit state of the third signal path for the CA mode is made different when the selected frequency band is different. More specifically, when the non-CA mode (middle band) is selected, one end of the third signal path 23B is opened, and when the non-CA mode (high band) And the other end is short-circuited.

This improves the isolation between the signal path in use and the third signal path as well as improves the isolation between the signal path in use and the third signal path as well as the impedance of the unused third signal path, It is possible to highly suppress the impedance mismatch of the first signal path and the second signal path.

In the present embodiment, the FET 221M for switching conduction and non-conduction between the other end of the first path 23B1 and the first signal path 23M is disposed in the first path 23B1, and the second path 23B2 Is provided with an FET 221H for switching conduction and non-conduction between the other end of the second path 23B2 and the second signal path 23H. In this configuration, the variable adjusting unit 25 sets the FET 221M to the non-conductive state when the non-CA mode (middle band) is selected and the FET 221H when the non-CA mode (high band) Nonconductive state.

When the first frequency band is selected in the non-CA mode, the first path 23B1 becomes a load impedance through the FET 221M which is capacitive with respect to the first signal path 23M. When the second frequency band is selected in the non-CA mode, the second path 23B2 becomes load impedance through the FET 221H which is capacitive with respect to the second signal path. In this case, since the impedance of the third signal path which is not used but is adjusted according to the pass band of the signal being used is improved individually, the isolation between the third signal path and the third signal path is improved, The impedance mismatching of the first signal path and the second signal path can be highly suppressed.

In the present embodiment, the switch circuit 20 includes the FETs 202M, 202B, and 202H for connecting the selection terminal and the ground terminal, but the configuration disposed between each selection terminal and the ground terminal is not limited to the FET .

9 is a circuit configuration diagram of the switch circuit 120 according to a modified example of the embodiment. As shown in Fig. 9, a variable matching circuit for varying the impedance when each selection terminal is viewed from each signal path may be disposed between each selection terminal and the ground terminal. That is, the switch circuit 20 includes a first variable matching circuit 302M disposed between the first selection terminal 20s1 and the ground terminal, a second variable matching circuit 302M disposed between the second selection terminal 20s2 and the ground terminal, And a third variable matching circuit 302B disposed between the third selection terminal 302H and the third selection terminal 20s3 and the ground terminal. In this case, the switch circuit 20 makes it possible to finely adjust the complex impedance when each selection terminal is seen from each signal path between the open state and the short state as well as the two states of the open state and the short state.

That is, when the non-CA mode is selected, the variable adjusting section 25 may adjust the third variable matching circuit.

In addition, the switch module according to the present invention can be applied not only to the impedance matching when the non-CA mode is selected, but also to the impedance matching when the CA mode is selected. That is, when the CA mode is selected, the variable adjustment unit 25 adjusts at least one of the first variable matching circuit and the second variable matching circuit, and when the non-CA mode is selected, the third variable matching circuit is adjusted do.

According to this, in the configuration having separate signal paths in the CA mode and the non-CA mode like the switch module 10 according to the present embodiment, the variable adjustment section 25 adjusts the impedance of the signal path used for wireless communication In addition, the impedance of the signal path not used for wireless communication is adjusted. Therefore, it is possible to improve the isolation between the signal path used in the wireless communication and the signal path not used, and to suppress the impedance mismatch in the signal path used for the wireless communication.

In addition, the variable adjusting unit 25 adjusts the impedance of the third variable matching circuit when the first frequency band is selected among the non-CA modes and the impedance of the third variable matching circuit when the second frequency band is selected among the non- The impedance of the matching circuit may be different.

Thus, even when the non-CA mode is selected, the impedance of the signal path used in the CA mode is different if the selected frequency band is different. Therefore, it is possible to adjust the impedance matching particularly in the non-CA mode with high accuracy according to the selected frequency band.

(Other embodiments, etc.)

As described above, the switch module and the driving method thereof according to the embodiment of the present invention have been described with reference to the embodiments and the modifications thereof, but the switch module and the driving method thereof according to the embodiment of the present invention are not limited to the embodiment and its modifications. It is to be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention, And various devices incorporating the switch module of the present disclosure are also included in the present invention.

For example, an embodiment of the present invention includes a switch module 10 having the above-described characteristic configuration, a duplexer (not shown) connected to the other end of the first signal path 23M or the other end of the second signal path 23H Or a front end module 1 having a front end module 12M or 12H.

The front-end module 1 may include a power amplifier 14M or 14H connected to the transmission-side terminal of the duplexer.

The front end module 1 may further include a low noise amplifier 13M or 13H connected to the reception side terminal of the duplexer.

It is possible to provide a front end module capable of reducing signal propagation loss in a system in which the CA mode and the non-CA mode can be selected by the configuration of the front end module 1. [

In the above embodiment, the variable adjustment unit 25 is a component of the switch module 10, but the variable adjustment unit 25 is not provided with the switch module 10 but is provided with the front end module 1 It is good. In this case, the front end module indicates the effect of the switch module 10 according to the embodiment.

Further, the variable adjustment unit 25 according to the present invention may be realized as an IC or an LSI (Large Scale Integration) which is an integrated circuit. The integrated circuit may be implemented by a dedicated circuit or a general-purpose processor. An FPGA (Field Programmable Gate Array) capable of being programmed after the LSI fabrication, or a reconfigurable processor capable of reconfiguring connection and setting of circuit cells in the LSI may be used. Alternatively, if an integrated circuit technology replacing the LSI by the advancement of semiconductor technology or another technique derived therefrom appears, integration of functional blocks may naturally be performed using the technology.

In the switch module, the front-end module, and the switch module according to the above-described embodiment and its modifications, although separate high-frequency circuit elements, wirings, and the like are inserted between the respective circuit elements and the paths connecting the signal paths good.

INDUSTRIAL APPLICABILITY The present invention can be widely applied to a communication device such as a cellular phone as a multi-band / multimode-compatible switch module employing a carrier aggregation method.

1: front end module 2: antenna element
3: RF signal processing circuit 10: Switch module
11, 21M: Low pass filter 12H, 12M: Duplexer
13H, 13M: Low Noise Amplifier 14H, 14M: Power Amplifier
20, 120: Switch circuit 20c: Common terminal
20s1: first selection terminal 20s2: second selection terminal
20s3: Third selection terminal 21H: High pass filter
22H, 22M: CA switch circuit 23B: third signal path
23B1: first path 23B2: second path
23H: second signal path 23M: first signal path
25:
201B, 201H, 201M, 202B, 202H, 202M, 221H, 221M: FET
302B: third variable matching circuit 302H: second variable matching circuit
302M: first variable matching circuit

Claims (9)

A carrier aggregation (CA) mode in which a first frequency band for wireless communication and a second frequency band for wireless communication different in frequency band from the first frequency band are used at the same time, A switch module capable of selecting a non-CA mode using only one of the bands,
A first signal path for propagating the signal of the first frequency band,
A second signal path for propagating the signal of the second frequency band,
A third signal path for simultaneously propagating the signal of the first frequency band and the signal of the second frequency band,
A first selection terminal connected to one end of the first signal path, a second selection terminal connected to one end of the second signal path, and a second selection terminal connected to one end of the third signal path, And a switch circuit exclusively switching the connection between the common terminal and any one of the first selection terminal, the second selection terminal and the third selection terminal,
Wherein the switch circuit includes a first variable matching circuit disposed between the first selection terminal and the ground terminal, a second variable matching circuit disposed between the second selection terminal and the ground terminal, and a second variable matching circuit disposed between the third selection terminal and the ground terminal And a third variable matching circuit disposed,
The switch module includes:
Wherein the third variable matching circuit is variably adjusted when the non-CA mode is selected, or when the CA mode is selected, the first variable matching circuit and the second variable matching circuit are variably adjusted And a control unit. The method according to claim 1,
The variable-
The impedance of the third variable matching circuit when the first frequency band is selected among the non-CA modes and the impedance of the third variable matching circuit when the second frequency band is selected among the non- A switch module with different impedance. 3. The method of claim 2,
Wherein the switch circuit includes a first switch element for switching conduction and non-conduction between the first selection terminal and the common terminal,
A second switch element for switching conduction and non-conduction between the second selection terminal and the common terminal,
Further comprising a third switch element for switching conduction and non-conduction of the third selection terminal and the common terminal,
The third variable matching circuit is a third shunt switch element for switching conduction and non-conduction between the third selection terminal and the ground terminal,
The variable-
When the first frequency band is selected among the non-CA modes, the third shunt switch element is made non-conductive, and when the second frequency band is selected among the non-CA modes, Switch module to put into conduction state. The method of claim 3,
Wherein the second frequency band is a frequency band allocated to a higher frequency side than the first frequency band. 5. The method according to any one of claims 1 to 4,
The third signal path having a first path selectively passing the first frequency band and a second path selectively passing the second frequency band,
One end of the third signal path is a point where one end of the first path and one end of the second path are connected,
A fourth switch element for switching conduction and non-conduction between the other end of the first path and the first signal path,
Further comprising a fifth switch element for switching conduction and non-conduction between the other end of the second path and the second signal path,
The variable-
When the first frequency band is selected among the non-CA modes, the fourth switch element is made non-conductive,
And switches the fifth switch element to a non-conductive state when the second frequency band is selected among the non-CA modes. A switch module according to any one of claims 1 to 4,
And a duplexer element connected to the other end of the first signal path or the other end of the second signal path. The method according to claim 6,
And a power amplifier element connected to the transmission-side terminal of the duplexer element. The method according to claim 6,
And a low-noise amplifier element connected to a receiving-side terminal of the duplexer element. A carrier aggregation (CA) mode in which a first frequency band for wireless communication and a second frequency band for wireless communication different in frequency band from the first frequency band are used at the same time, A method of driving a switch module for selecting a non-CA mode using only one of the bands,
The switch module includes:
A first signal path for propagating the signal of the first frequency band,
A second signal path for propagating the signal of the second frequency band,
A third signal path for simultaneously propagating the signal of the first frequency band and the signal of the second frequency band,
A first selection terminal connected to one end of the first signal path, a second selection terminal connected to one end of the second signal path, and a second selection terminal connected to one end of the third signal path, And a switch circuit which has a selection terminal and exclusively switches the connection between the common terminal and any one of the first selection terminal, the second selection terminal and the third selection terminal,
Wherein the switch circuit includes a first variable matching circuit disposed between the first selection terminal and the ground terminal, a second variable matching circuit disposed between the second selection terminal and the ground terminal, and a second variable matching circuit disposed between the third selection terminal and the ground terminal And a third variable matching circuit disposed,
Wherein when the CA mode is selected, at least one of the first variable matching circuit and the second variable matching circuit is variably adjusted, or when the non-CA mode is selected, a switch for variably adjusting the third variable matching circuit A method of driving a module.

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