Configurable radio frequency (RF) multiplexing switch for RF front end in 4G/5G applications

Patent metadata

Field	Value
Publication number	US-12334960-B2
Application number	US-202217872912-A
Country	US
Kind code	B2
Filing date	Jul 25, 2022
Priority date	Jul 25, 2022
Publication date	Jun 17, 2025
Grant date	Jun 17, 2025

Abstract

An RF multiplexing switching circuit for an RF front end (e.g., for a mobile communications device transmitting/receiving in the RF region) includes a set of RF inputs and a set of RF outputs outputting to RF filters, the RF inputs and outputs connected by signal paths. The switching circuit includes series switches for creating conducting signal paths for transmitting/receiving RF signals between the RF inputs and outputs, and a set of common shared shunt switches (e.g., for M RF inputs and N RF outputs, M+X shunt switches, where X<N) collectively capable (e.g., in conjunction with the series switches) of pulling to ground potential any RF input and output not on the conducting signal path. The RF switching circuit may be implemented as a band select switch (e.g., where the inputs connect to power amplifiers) or an antenna switch (e.g., where the inputs connect to device antennas).

First claim

We claim:

1. A circuit comprising:
a set of M radio frequency (RF) input ports, wherein M is an integer;
a set of N RF output ports, wherein Nis an integer, the M RF input ports operatively coupled to the N RF output ports by a set of RF signal paths, each RF output port operatively coupled to one or more RF filters;
a set of series switches, each series switch configured to create a conducting signal path based on an RF signal path operatively coupling an RF input port and an RF output port;
a set of M+X shunt switches, wherein X is an integer less than N, the set of shunt switches being connected to at least one RF ground for each RF input port and each RF output port not associated with the conducting signal path;
wherein the set of series switches includes a first series switch adjacent to a first RF output port and configured to create, by closing, a conducting signal path based on an RF signal path operatively coupling a first RF input port and the first RF output port.

2. The circuit of claim 1 , wherein the set of M RF input ports includes:
a first RF input port operatively coupled to each of the N RF output ports by an RF signal path; and
M−1 RF input ports operatively coupled to each of N−1 RF output ports by an RF signal path and not operatively coupled to a first RF output port by an RF signal path.

3. The circuit of claim 2 , wherein the set of M+X shunt switches includes:
an output shunt switch adjacent to the first RF output port;
and
M input shunt switches, each input shunt switch adjacent to an RF input port of the M RF input ports.

4. The circuit of claim 1 , wherein:
the circuit is a band select switching circuit;
wherein each RF filter is associated with at least one RF frequency band;
and
wherein each RF input port is operatively coupled to at least one RF amplifier.

5. The circuit of claim 1 , wherein:
the circuit is an antenna switching circuit;
and
wherein each RF input port is operatively coupled to at least one antenna.

6. The circuit of claim 5 , wherein:
the circuit is configurable in an isolation mode by closing each series switch and each shunt switch.

7. The circuit of claim 1 , wherein the set of series switches includes:
one or more second series switches adjacent to the first RF output port, the one or more second series switches configured to isolate, by opening, the first RF output port from the remaining RF input ports to which the first RF output port is operatively coupled by an RF signal path;
one or more third series switches, each third series switch adjacent to an RF output port 1) other than the first RF output port and 2) that is operatively coupled to the first RF input port by an RF signal path, each third series switch configured to isolate, by opening, the adjacent RF output port from the conducting signal path;
and
at least one fourth series switch adjacent to an RF output port 1) other than the first RF output port and 2) that is not operatively coupled to the first RF input port by an RF signal path, each fourth series switch configured to connect, by closing, the adjacent RF output port and the at least one RF ground.

8. The circuit of claim 7 , wherein the set of M+X shunt switches includes:
a first shunt switch adjacent to the first RF input port, the first shunt switch configured to isolate, by opening, the conducting signal path from the at least one RF ground;
and
a set of one or more shunt switches configured to close in conjunction with the at least one fourth series switch.

9. The circuit of claim 1 , wherein the circuit is an RF front-end circuit embodied in a mobile communications device.

10. The circuit of claim 1 , wherein:
the set of M RF input ports is a set of two (2) RF input ports;
the set of N RF output ports is a set of four (4) RF output ports;
and
the set of series switches is a set of seven (7) series switches.

11. A radio frequency (RF) front end, comprising:
at least one transceiver configured to transmit and receive one or more radio frequency (RF) signals;
at least one antenna;
one or more RF filters, each RF filter configured for filtering of the one or more RF signals and associated with an RF frequency band;
and
at least one RF front-end circuit connecting at least one transceiver or the at least one antenna to the one or more RF filters, the at least one RF front-end circuit comprising:
a set of M radio frequency (RF) input ports, wherein M is an integer;
a set of N RF output ports, wherein Nis an integer, the M RF input ports operatively coupled to the N RF output ports by a set of RF signal paths, each RF output port operatively coupled to one or more RF filters;
a set of series switches, each series switch configured to create a conducting signal path based on an RF signal path operatively coupling an RF input port and an RF output port;
a set of M+X shunt switches, wherein X is an integer less than N, the set of shunt switches being connected to at least one RF ground for each RF input port and each RF output port not associated with the conducting signal path;
wherein the set of series switches includes a first series switch adjacent to a first RF output port and configured to create, by closing, a conducting signal path based on an RF signal path operatively coupling a first RF input port and the first RF output port.

12. The RF front end of claim 11 , wherein the set of M RF input ports includes:
a first RF input port operatively coupled to each of the N RF output ports by an RF signal path;
and
M−1 RF input ports operatively coupled to each of N−1 RF output ports by an RF signal path and not operatively coupled to a first RF output port by an RF signal path.

13. The RF front end of claim 12 , wherein the set of M+X shunt switches includes:
an output shunt switch adjacent to the first RF output port;
and
M input shunt switches, each input shunt switch adjacent to an RF input port of the M RF input ports.

14. The RF front end of claim 11 , further comprising:
one or more RF amplifiers including at least one of a power amplifier (PA) or a low noise amplifier (LNA);
wherein;
the circuit is a band select switching circuit;
and
each RF input port is operatively coupled to at least one RF amplifier of the one or more RF amplifiers.

15. The RF front end of claim 11 , wherein:
the circuit is an antenna switching circuit;
and
wherein each RF input port is operatively coupled to at least one antenna of the one or more antennas.

16. The RF front end of claim 15 , wherein the circuit is configurable in an isolation mode by closing each series switch and each shunt switch.

17. The RF front end of claim 11 , wherein the set of series switches includes:
one or more second series switches adjacent to the first RF output port, the one or more second series switches configured to isolate, by opening, the first RF output port from the remaining RF input ports to which the first RF output port is operatively coupled by an RF signal path;
one or more third series switches, each third series switch adjacent to an RF output port 1) other than the first RF output port and 2) that is operatively coupled to the first RF input port by an RF signal path, each third series switch configured to isolate, by opening, the adjacent RF output port from the conducting signal path;
and
at least one fourth series switch adjacent to an RF output port 1) other than the first RF output port and 2) that is not operatively coupled to the first RF input port by an RF signal path, each fourth series switch configured to connect, by clos

Assignees

• Avago Tech Int Sales Pte Lid

Inventors

• Luo Yuan
• Jin Yalin
• Wang Shang
• Kim Jeesu

Classifications

• H04B1/04 Primary

  Circuits · CPC title

• H04B2001/307

  using n-port mixer · CPC title

• H04B1/30

  for homodyne or synchrodyne receivers (demodulator circuits H03D1/22) · CPC title

• H04B2001/0408

  with power amplifiers · CPC title

• H04B1/006

  using switches for selecting the desired band (H04B1/0057 takes precedence) · CPC title