LOW-LOSS HIGH-ISOLATION SWITCHING ARCHITECTURE

• US 20130321095A1
• Filed: 05/10/2013
• Published: 12/05/2013
• Est. Priority Date: 05/11/2012
• Status: Active Grant

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Lam, Lui, Vaillancourt, William Gerard
• Granted Patent: US 9,306,526 B2
• Time in Patent Office: Days
• US Class Current: 333/103
• CPC Class Codes: H03H 2/005 Coupling circuits between transmission lines or antennas and transmitters, receivers or amplifiers
• CPC Class Codes: H04B 1/44 Transmit/receive switching
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Disclosed are switching circuits and methods that enable a device to switch between two wireless protocols with antenna sharing. In some implementations, the device may use two different wireless protocols concurrently and with high isolation. In some implementations, the device can be provided with insertion loss matched transmission diversity for one of the wireless protocols. In some embodiments, various signal paths and related switches that allow such functionalities can be implemented on a single die such as a silicon-on-insulator (SOI) die.

Claims

1. A switching circuit comprising:

a first signal path between a transmit terminal and a first antenna terminal;

a second signal path between the transmit terminal and a second antenna terminal, the switching circuit configured to be capable of operating in a first mode in which the transmit terminal is provided with access to the first antenna terminal through the first signal path with a first insertion loss or the second antenna terminal through the second signal path with a second insertion loss, the first insertion loss substantially matching the second insertion loss; and

a third signal path between a transceiver terminal and the second antenna terminal, the switching circuit further configured to be capable of operating in a second mode in which the transmit terminal is provided with access to the first antenna terminal and the transceiver terminal is concurrently provided with access to the second antenna terminal.

2. The switching circuit of claim 1 wherein the first signal path includes a switch and an insertion loss component connected in series.

3. The switching circuit of claim 2 wherein the insertion loss component includes an additional switch.

4. The switching circuit of claim 2 further comprising a switchable shunt circuit that couples a node between the switch and the transmit terminal with an electrical ground.

5. The switching circuit of claim 1 wherein the second signal path includes a first switch in series with a second switch.

6. The switching circuit of claim 5 further comprising a switchable shunt circuit that couples a node between the first and second switches of the second signal path with an electrical ground.

7. The switching circuit of claim 1 wherein the third signal path is a bidirectional signal path.

8. The switching circuit of claim 7 wherein the bidirectional signal path includes a switch.

9. The switching circuit of claim 8 further comprising a switchable shunt circuit that couples a node between the switch and the transceiver terminal with an electrical ground.

10. The switching circuit of claim 1 further comprising a fourth signal path between a receive terminal and the first antenna terminal.

11. The switching circuit of claim 10 wherein the fourth signal path includes a switch.

12. The switching circuit of claim 11 further comprising a switchable shunt circuit that couples a node between the switch and the receive terminal with an electrical ground.

13. The switching circuit of claim 10 further comprising a fifth signal path between the receive terminal and the second antenna terminal.

14. The switching circuit of claim 13 wherein the fifth signal path includes a first switch in series with a second switch.

15. The switching circuit of claim 14 further comprising a switchable shunt circuit that couples a node between the first and second switches with an electrical ground.

16. The switching circuit of claim 13 wherein the switching circuit is further configured to be capable of operating in a third mode in which the receive terminal is provided with access to the first antenna terminal or the second antenna terminal.

17. The switching circuit of claim 13 wherein at least the first, second and third signal paths are formed on a common die.

18. The switching circuit of claim 1 wherein the transmit terminal is for connection to a transmitter operating in accordance with a first wireless protocol which utilizes transmission diversity, and the transceiver terminal is for connection to a transceiver operating in accordance with a second wireless protocol.

19. A die having a switching circuit, the die comprising:

a substrate that includes a semiconductor material;

a transmit terminal, a transceiver terminal, a first antenna terminal, and a second antenna terminal, each formed on the substrate;

a first signal path formed on the substrate, the first signal path configured to allow the transmit terminal to be in communication with the first antenna terminal with a first insertion loss;

a second signal path formed on the substrate, the second signal path configured to allow the transmit terminal to be in communication with the second antenna terminal with a second insertion loss, the first insertion loss substantially matching the second insertion loss; and

a third signal path formed on the substrate, the third signal path configured to allow the transceiver terminal to be in communication with the second antenna terminal.

20. The die of claim 19 wherein the die is a silicon-on-insulator (SOI) die.

21. A wireless device comprising:

a plurality of antennas;

a first radio-frequency (RF) circuit capable of being in communication with one or more of the plurality of antennas, the first RF circuit configured to operate with a first communication protocol;

a second RF circuit capable of being in communication with one or more of the plurality of antennas, the second RF circuit configured to operate with a second communication protocol; and

a switching module having a switching circuit implemented on a common die, the switching circuit configured to allow antenna-sharing and antenna-diversity among the first and second radio-frequency circuits operating with their respective communication protocols.