CN218041363U

CN218041363U - Radio frequency switch circuit

Info

Publication number: CN218041363U
Application number: CN202221806048.8U
Authority: CN
Inventors: 丁佳佳; 刘刚; 江海波; 郭天生; 赵鹏
Original assignee: Jiangsu Qianhe Microelectronics Co ltd
Current assignee: Jiangsu Qianhe Microelectronics Co ltd
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2022-12-13
Anticipated expiration: 2032-07-14

Abstract

The utility model relates to a radio frequency switch technical field, the utility model discloses a radio frequency switch circuit, including radio frequency switch branch road and switching circuit, the radio frequency switch branch road includes the MOS pipe of two at least series connections, the grid electricity of every MOS pipe is connected with the biasing resistance, every biasing resistance is not all connected with input resistance one end electricity with the one end that corresponds the MOS union coupling, every biasing resistance's both ends are parallelly connected to have switching circuit, switching circuit is with the biasing resistance bypass when the voltage sudden change at biasing resistance both ends, when using, when the biasing voltage of inputing the MOS pipe takes place to switch over, the voltage at biasing resistance both ends can take place the sudden change, switching circuit is through letting the biasing resistance bypass, can let the grid quick charge of MOS pipe, let the MOS pipe open fast and close, after MOS pipe charge-discharge is accomplished, biasing resistance both ends voltage recovery is stable, thereby let the MOS pipe continue to switch on, do not influence MOS switching circuit's radio frequency performance, thereby can guarantee radio frequency switch's stability in the reduction radio frequency switch changeover time.

Description

Radio frequency switch circuit

Technical Field

The utility model relates to a radio frequency switch technical field, concretely relates to radio frequency switch circuit.

Background

The radio frequency switch circuit is an important component of the radio frequency module and is mainly used for realizing switching of signal channels. The core of the switch is usually a radio frequency switch branch formed by connecting a plurality of MOS tubes in series. As shown in fig. 1, the conventional rf switch circuit is formed by connecting a MOS transistor M1, a MOS transistor M2, a MOS transistor M3, a MOS transistor M4, and a MOS transistor M5 in series, that is, the source of the previous MOS transistor is electrically connected to the drain of the next MOS transistor. Due to the parasitic capacitance of the MOS transistor, when a radio frequency signal changes, if a bias resistor is not arranged on a gate of the MOS transistor or the resistance of the bias resistor is small, the gate-source voltage of the MOS transistor may not be stable, and the MOS transistor frequently switches a switch, so that the stability of the radio frequency switch circuit in use is affected, and therefore, in fig. 1, gates of the MOS transistor M1 to the MOS transistor M5 are respectively connected with a resistor.

However, after the bias resistor with a large resistance value is arranged, the bias voltage input to the gate of the MOS transistor is delayed greatly due to the RC delay circuit formed by the bias resistor and the parasitic capacitor of the MOS transistor, which results in an overlong switching time of the radio frequency switch.

SUMMERY OF THE UTILITY MODEL

In view of the deficiency of the background art, the utility model provides a radio frequency switch circuit can descend radio frequency switch's switching time under the prerequisite of guaranteeing job stabilization nature.

For solving the technical problem, the utility model provides a following technical scheme: the radio frequency switch circuit comprises a radio frequency switch branch circuit, wherein the radio frequency switch branch circuit comprises at least two MOS (metal oxide semiconductor) tubes, all the MOS tubes are sequentially connected in series, the series connection means that the source electrode of the previous MOS tube is electrically connected with the drain electrode of the next MOS tube, the grid electrode of each MOS tube is electrically connected with a bias resistor, and one end of each bias resistor, which is not electrically connected with the corresponding MOS tube, is electrically connected with one end of an input resistor;

the switching circuit is characterized by further comprising a switching circuit, wherein two ends of each bias resistor are respectively and electrically connected with the first connecting end and the second connecting end of one switching circuit, and the switching circuit bypasses the bias resistors when the voltages at the two ends of the bias resistors are suddenly changed.

In one embodiment, the two ends of the input resistor are electrically connected to a first connection end and a second connection end of a switching circuit, and the switching circuit bypasses the input resistor when the voltage across the input resistor changes abruptly.

In one embodiment, the switching circuit includes a bidirectional diode.

In a certain embodiment, the rf switch branch includes five MOS transistors, which are respectively a MOS transistor M1, a MOS transistor M2, a MOS transistor M3, a MOS transistor M4, and a MOS transistor M5, a source of the MOS transistor M1 is electrically connected to a drain of the MOS transistor M2, a source of the MOS transistor M2 is electrically connected to a drain of the MOS transistor M3, a source of the MOS transistor M3 is electrically connected to a drain of the MOS transistor M4, a source of the MOS transistor M4 is electrically connected to a drain of the MOS transistor M5, a gate of the MOS transistor M1, a gate of the MOS transistor M2, a gate of the MOS transistor M3, a gate of the MOS transistor M4, and a gate of the MOS transistor M5 are respectively electrically connected to one bias resistor, and ends of the five bias resistors, which are not electrically connected to the MOS transistors, are electrically connected to one end of the input resistor.

Compared with the prior art, the utility model beneficial effect who has is: in the time of in-service use, when the bias voltage who inputs the MOS pipe takes place to switch over, the voltage at bias resistance both ends can take place the sudden change, switching circuit is through letting the bias resistance bypass, can let the grid quick charge of MOS pipe, can let the MOS pipe open fast and close, after the grid charge-discharge of MOS pipe is accomplished, bias resistance both ends voltage recovery is stable, thereby let the MOS pipe continue to switch on, do not influence MOS switch circuit's radio frequency performance, thereby can guarantee radio frequency switch's stability in use when reducing radio frequency switch switching time.

Drawings

FIG. 1 is a circuit diagram of a conventional RF switch circuit;

fig. 2 is a first schematic structural diagram of the present invention in an embodiment;

fig. 3 is a second schematic structural diagram of the present invention in an embodiment;

FIG. 4 is a schematic diagram of a negative voltage ripple simulation of the circuit shown in FIG. 1;

FIG. 5 is a schematic diagram of a negative voltage ripple simulation of the circuit shown in FIG. 3;

FIG. 6 is a simulation diagram of the switching time of the circuit shown in FIG. 1;

FIG. 7 is a simulation diagram of the switching time of the circuit shown in FIG. 3.

Detailed Description

The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic drawings and illustrate the basic structure of the present invention only in a schematic manner, and thus show only the components related to the present invention.

As shown in fig. 2, the radio frequency switch circuit includes a radio frequency switch branch 1, where the radio frequency switch branch includes five MOS transistors, that is, a MOS transistor M1, a MOS transistor M2, a MOS transistor M3, a MOS transistor M4, and a MOS transistor M5, a source of the MOS transistor M1 is electrically connected to a drain of the MOS transistor M2, a source of the MOS transistor M2 is electrically connected to a drain of the MOS transistor M3, a source of the MOS transistor M3 is electrically connected to a drain of the MOS transistor M4, a source of the MOS transistor M4 is electrically connected to a drain of the MOS transistor M5, a gate of each MOS transistor is electrically connected to a bias resistor, a gate of the MOS transistor M1, a gate of the MOS transistor M2, a gate of the MOS transistor M3, and a gate of the MOS transistor M5 are electrically connected to one bias resistor, the five bias resistors are a resistor R1, a resistor R2, a resistor R3, a resistor R4, and a resistor R5, and one end of the five bias resistors that are not electrically connected to the MOS transistor is electrically connected to one end of an input resistor R6;

in actual use, bias voltage is input to the grid electrode of the MOS tube through the input resistor R6 and the bias resistor to charge the MOS tube;

additionally, the utility model discloses still include switching circuit 2, every biasing resistance's both ends are connected with a switching circuit 2's first link and second link electricity respectively, and switching circuit 2 is with the biasing resistance bypass when the voltage sudden change at biasing resistance both ends.

In the time of in-service use, when the bias voltage who inputs the MOS pipe takes place to switch over, the voltage at bias resistance both ends can take place the sudden change, switching circuit 2 is through letting the bias resistance bypass, can let the grid quick charge of MOS pipe, can let the MOS pipe open fast and close, after the grid charge-discharge of MOS pipe is accomplished, bias resistance both ends voltage recovery is stable, thereby let the MOS pipe continue to switch on, do not influence MOS switch circuit's radio frequency performance, thereby can guarantee radio frequency switch's stability in use when reducing radio frequency switch switching time

As shown in fig. 3, in order to further reduce the switching time of the present invention, the two ends of the input resistor R6 are electrically connected to the first connection end and the second connection end of the switching circuit 2, and the switching circuit 2 bypasses the input resistor R6 when the voltages at the two ends of the input resistor suddenly change.

In the circuits shown in fig. 2 and 3, the switching circuit 2 includes a bidirectional diode.

In certain embodiment, the number of MOS transistors in the rf switch branch 1 may be increased or decreased according to actual requirements.

With reference to fig. 4 and 5, it can be seen from the comparison of the ripple wave of the negative pressure before and after the simulation, the transmission stability of the radio frequency signal of the present invention is improved; combine fig. 6 and fig. 7, when having increased biasing resistance and input resistance R6 and improved radio frequency signal transmission stability, because bidirectional diode's existence, the radio frequency switch switching time also correspondingly improves, the utility model discloses a switching time obtains reducing.

In light of the above, the present invention is not limited to the above embodiments, and various changes and modifications can be made by the worker without departing from the scope of the present invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.

Claims

1. The radio frequency switch circuit is characterized by further comprising a switching circuit, wherein two ends of each biasing resistor are respectively electrically connected with a first connecting end and a second connecting end of one switching circuit, and the switching circuit bypasses the biasing resistors when the voltages at the two ends of the biasing resistors suddenly change.

2. The radio frequency switch circuit according to claim 1, wherein both ends of the input resistor are electrically connected to a first connection end and a second connection end of a switching circuit, the switching circuit bypassing the input resistor when a voltage across the input resistor abruptly changes.

3. The radio frequency switch circuit of claim 1 or 2, wherein the switching circuit comprises a bidirectional diode.

4. The radio frequency switch circuit according to claim 1, wherein the radio frequency switch branch comprises five MOS transistors, which are MOS transistor M1, MOS transistor M2, MOS transistor M3, MOS transistor M4 and MOS transistor M5, respectively, a source of MOS transistor M1 is electrically connected to a drain of MOS transistor M2, a source of MOS transistor M2 is electrically connected to a drain of MOS transistor M3, a source of MOS transistor M3 is electrically connected to a drain of MOS transistor M4, a source of MOS transistor M4 is electrically connected to a drain of MOS transistor M5, a gate of MOS transistor M1, a gate of MOS transistor M2, a gate of MOS transistor M3, a gate of MOS transistor M4 and a gate of MOS transistor M5 are electrically connected to a bias resistor, respectively, and one end of the five bias resistors, which is not electrically connected to the MOS transistors, is electrically connected to one end of the input resistor.