High-power switch
View Patent ↗A low-loss Radio Frequency (RF) switch for high-power RF signals. The RF switch includes a first-biasing circuit connected to a first transistor and a second-biasing circuit connected to a second transistor. The RF switch switches its output signal between a first input signal and a second input signal. The first transistor is in a conduction state and the second transistor is in a non-conduction state when the first input signal is to be conducted to the output signal. The first-biasing circuit biases the first transistor at a first voltage for increasing conduction of the first input signal and the second-biasing circuit biases the second transistor at a second voltage for decreasing conduction of the first input signal. Moreover, the second transistor is in a conduction state and the first transistor is in a non-conduction state when the second input signal is to be conducted to the output signal.
1. A Radio Frequency (RF) switch, the RF switch comprising at least a first transistor and a second transistor, wherein the first transistor receives a first input signal and the second transistor receives a second input signal, the RF switch providing at least one output signal, the at least one output signal being based on conduction of one of the first input signal by the first transistor and conduction of the second input signal by the second transistor, the RF switch comprising:
a. at least one first-biasing circuit, the at least one first-biasing circuit being connected to the first transistor, the at least one first-biasing circuit provides a first bias voltage at a gate terminal of the first transistor to increase conduction capability of the first transistor when the first transistor is in a conducting state and the second transistor is in a non-conducting state, wherein the at least one first-biasing circuit comprises:
i. at least one of one or more first capacitors and one or more first resistors, wherein the one or more capacitors are connected to the first transistor and the one or more first resistors, the one or more first capacitors coupling the first input signal with the at least one first-biasing circuit; and
ii. one or more first diode detectors; and
b. at least one second-biasing circuit, the at least one second-biasing circuit being connected to the second transistor, the at least one second-biasing circuit provides a second bias voltage at a gate terminal of the second transistor to decrease conduction capability of the second transistor when the first transistor is in the conducting state and the second transistor is in the non-conducting state, wherein the at least one second-biasing circuit comprises:
i. at least one of one or more second capacitors, one or more second resistors and one or more transistors; and
ii. one or more second diode detectors, wherein the one or more second diode detectors are connected in series as a series-diode detector, the series-diode detector being connected to the one or more transistors and the one or more second capacitors.
2. The RF switch of claim 1 , wherein the at least one first-biasing circuit and the at least one second-biasing circuit is a half-wave rectifier circuit.
3. The RF switch of claim 1 , wherein the one or more first capacitors reduces ripple in the first bias voltage.
4. The RF switch of claim 1 , wherein the one or more first diode detectors are connected between the one or more first resistors and a ground voltage terminal.
5. The RF switch of claim 1 , wherein the one or more first resistors are connected to the first transistor and the one or more first capacitors.
6. The RF switch of claim 1 , wherein at least one of the one or more first resistors are connected to at least one of the one or more first diode detectors and a first control voltage.
7. The RF switch of claim 1 , wherein the one or more second capacitors are connected to the second transistor and the one or more second diode detectors, the one or more second capacitors reducing ripple in the second bias voltage.
8. The RF switch of claim 1 , wherein the one or more second capacitors are connected to the second transistor and the one or more second diode detectors, the one or more second capacitors coupling the first input signal with the at least one second-biasing circuit.
9. The RF switch of claim 1 , wherein the one or more second resistors are connected to the second transistor, the one or more transistors and a second control voltage.
10. The RF switch of claim 9 , wherein the one or more transistors are connected to the second control voltage, a ground voltage terminal, the one or more second resistors and the one or more second diode detectors.
11. A Radio Frequency (RF) switch, the RF switch comprising at least a first transistor and a second transistor, wherein an input signal to be conducted is applied to one of the first transistor and the second transistor, the RF switch providing at least one output signal, the at least one output signal being based on the conduction of the input signal, the RF switch comprising:
a. at least one first-biasing circuit, the at least one first-biasing circuit being connected to the first transistor, the at least one first-biasing circuit provides a first bias voltage at a gate terminal of the first transistor to decrease conduction capability of the first transistor when the input signal is applied to the second transistor, wherein the at least one first-biasing circuit comprises:
i. at least one of one or more capacitors, one or more resistors and one or more transistors, wherein the one or more capacitors are connected to the first transistor, the one or more resistors and the one or more diode detectors, the one or more capacitors coupling the input signal with the at least one first-biasing circuit; and
ii. one or more diode detectors, wherein the one or more diode detectors are connected in series as a series-diode detector, the series-diode detector being connected to the one or more transistors, the one or more resistors, the one or more capacitors and the first transistor; and
b. at least one second-biasing circuit, the at least one second-biasing circuit being connected to the second transistor, the at least one second-biasing circuit provides a second bias voltage at a gate terminal of the second transistor to decrease conduction capability of the second transistor when the input signal is applied to the first transistor.
12. The RF switch of claim 11 , wherein the at least one first-biasing circuit and the at least one second-biasing circuit are symmetrical, the at least one first-biasing circuit and the at least one second-biasing circuit being half-wave rectifier circuits.
13. The RF switch of claim 11 , wherein the one or more capacitors are connected to the first transistor, the one or more resistors and the one or more diode detectors, the one or more capacitors reducing ripple in the first bias voltage.
14. The RF switch of claim 11 , wherein the one or more resistors are connected to the first transistor, the one or more diode detectors, the one or more capacitors, the one or more transistors and a first control voltage.
15. The RF switch of claim 14 , wherein the one or more transistors are connected to the first control voltage, the one or more resistors, the one or more diode detectors and a ground voltage terminal.
16. A Radio Frequency (RF) switch, the RF switch comprising at least a first transistor and a second transistor, wherein an input signal to be conducted is applied to one of the first transistor and the second transistor, the RF switch providing an output signal, the output signal being based on conduction of the input signal by at least one of the first transistor and the second transistor, the RF switch comprising:
a. at least one first-biasing circuit, the at least one first-biasing circuit being connected to the input signal and the first transistor, wherein the input signal is coupled to the at least one first-biasing circuit through a one or more capacitors, the at least one first-biasing circuit provides a first bias voltage at a gate terminal of the first transistor to increase conduction capability of the first transistor when the first transistor is in a conducting state and the second transistor is in a non-conducting state; and
b. at least one second-biasing circuit, the at least one second-biasing circuit being connected to the second transistor, the at least one second-biasing circuit providing a second bias voltage at a gate terminal of the second transistor to decrease conduction capability of the second transistor when the first transistor is in the conducting state and the second transistor is in the non-conducting state, wherein the at least one second-biasing circuit comprises at least one third transistor, the at least one third transistor enables activation of the at least one second-biasing circuit.
17. The RF switch of claim 16 , wherein the first bias voltage is a positive voltage and the second bias voltage is a negative voltage.
18. The RF switch of claim 16 , wherein the at least one first-biasing circuit and the at least one second-biasing circuit is a half-wave rectifier circuit, the at least one first-biasing circuit and the at least one second-biasing circuit being integrated with the RF switch, whereby the impedance to a ground is increased and the insertion loss is minimized.
19. The RF switch of claim 16 , wherein the one or more capacitors reduces ripple in the first bias voltage.
20. The RF switch of claim 16 , wherein conduction of the first transistor is enabled by means of a first control voltage applied to the gate terminal of the first transistor.
21. The RF switch of claim 20 , wherein conduction of the second transistor is disabled by means of a second control voltage applied to the gate terminal of the second transistor, the second control voltage having a polarity opposite to that of the first control voltage.