U.S. patent application number 16/428269 was filed with the patent office on 2020-08-20 for radio frequency switching circuit.
This patent application is currently assigned to Shanghai Huahong Grace Semiconductor Manufacturing Corporation. The applicant listed for this patent is Shanghai Huahong Grace Semiconductor Manufacturing Corporation. Invention is credited to Ruofan DAI.
Application Number | 20200266812 16/428269 |
Document ID | 20200266812 / US20200266812 |
Family ID | 1000004141923 |
Filed Date | 2020-08-20 |
Patent Application | download [pdf] |
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United States Patent
Application |
20200266812 |
Kind Code |
A1 |
DAI; Ruofan |
August 20, 2020 |
Radio Frequency Switching Circuit
Abstract
a radio frequency (RF) switching circuit, including: a
conducting module, configured to conduct an RF signal; a gate
control voltage generating module, configured to provide a gate
control voltage for the conducting module to control the conducting
module operating at ON-state or OFF-state; wherein the gate control
voltage generating module further includes: a first resistance
adaptive module, providing a first impedance in a first state for a
series branch where the conducting module and the gate control
voltage generation module locate, and a second impedance in a
second state for the series branch where the conducting module and
the gate control voltage generation module locate, wherein the
first impedance is greater than the second impedance. FOM is
improved comprehensively, and Ron, Coff, and a power breakdown
performance are optimized, which further improves circuit
performance and reduces cost.
Inventors: |
DAI; Ruofan; (Shanghai,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shanghai Huahong Grace Semiconductor Manufacturing
Corporation |
Shanghai |
|
CN |
|
|
Assignee: |
Shanghai Huahong Grace
Semiconductor Manufacturing Corporation
Shanghai
CN
|
Family ID: |
1000004141923 |
Appl. No.: |
16/428269 |
Filed: |
May 31, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H03K 17/063 20130101;
H03K 17/687 20130101; H03K 2217/0054 20130101 |
International
Class: |
H03K 17/06 20060101
H03K017/06; H03K 17/687 20060101 H03K017/687 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 14, 2019 |
CN |
201910114122.6 |
Claims
1. A radio frequency (RF) switching circuit comprising: a
conducting module, configured to conduct an RF signal; and a gate
control voltage generating module, configured to provide a gate
control voltage for the conducting module to control the conducting
module operating at ON-state or OFF-state; wherein the gate control
voltage generating module further comprises: a first resistance
adaptive module, providing a first impedance in a first state for a
series branch where the conducting module and the gate control
voltage generation module locate, and a second impedance in a
second state for the series branch where the conducting module and
the gate control voltage generation module locate, wherein the
first impedance is greater than the second impedance, the first
resistance adaptive module is in the first state when the RF signal
operated by the conducting module is a high power signal or the
conducting module is turned on, and the first resistance adaptive
module is in the second state when the conducting module does not
operate the high power signal and the conducting module is turned
off.
2. The RF switching circuit according to claim 1, wherein the gate
control voltage generating module further comprises a first level
shifter circuit and a first filter circuit, wherein the first level
shifter circuit and the first filter circuit respectively are
configured to perform a level shifting on the first control voltage
and to filter the level shifted voltage.
3. The RF switching circuit according to claim 1, wherein the first
resistance adaptive module comprises: a first NOR gate, comprising
a first input end, a second input end and an output end, wherein
the first input end is configured to receive the first control
voltage, the second input end is configured to receive a high power
enable signal, and the output end is configured to output the
resistance adaptive control signal; a first adaptive switch,
configured to receive the resistance adaptive control signal,
wherein the first adaptive switch is configured to turn on when the
resistance adaptive control signal is high, and turn off when the
resistance adaptive control signal is low; and a first common bias
resistor, coupled in parallel with the first adaptive switch.
4. The RF switching circuit according to claim 1, wherein the first
resistance adaptive module comprises: a first NOR gate, comprising
a first input end, a second input end and an output end, wherein
the first input end is configured to receive the first control
voltage, the second input end is configured to receive a high power
enable signal, and the output end is configured to output a
resistance adaptive control signal; and a first NMOS transistor,
comprising a gate, wherein the gate is configured to receive the
resistance adaptive control signal.
5. The RF switching circuit according to claim 1 further
comprising: a body control voltage generating module, configured to
provide a body control voltage for the conducting module to control
the conducting module operating at ON-state or OFF-state; wherein
the body control voltage generating module comprises: a second
resistance adaptive module, in series with the conducting module to
form a series branch, and providing a first impedance for the
series branch in the first state and a second impedance for the
series branch in the second state, wherein the first impedance is
greater than the second impedance, the second resistance adaptive
module is in the first state when the RF signal operated by the
conducting module is a high power signal or the conducting module
is turned on, and the second resistance adaptive module is in the
second state when the conducting module does not operate the high
power signal and the conducting module is turned off.
6. The RF switching circuit according to claim 5, wherein the body
control voltage generating module further comprises a second level
shifter circuit and a second filter circuit, wherein the second
level shifter circuit and the second filter circuit are
respectively configured to perform a level shifting on the second
control voltage and to filter the level shifted voltage.
7. The RF switching circuit according to claim 5, wherein the
second resistance adaptive module comprises: a second NOR gate,
comprising a first input end, a second input end and an output end,
wherein the first input end is configured to receive a second
control voltage, the second input end is configured to receive a
high power enable signal, and the output end is configured to
output the resistance adaptive control signal; a second adaptive
switch, configured to receive the resistance adaptive control
signal, wherein the second adaptive switch turns on when the
resistance adaptive control signal is high, and turns off when the
resistance adaptive control signal is low; and a second common bias
resistor, coupled in parallel with the second adaptive switch.
8. The RF switching circuit according to claim 5, wherein the
second resistance adaptive module comprises: a second NOR gate,
comprising a first input end, a second input end and an output end,
wherein the first input end is configured to receive the second
control voltage, the second input end is configured to receive a
high power enable signal, and the output end is configured to
output a resistance adaptive control signal; and a second NMOS
transistor, comprising a gate, wherein the gate is configured to
receive the resistance adaptive control signal.
9. The RF switching circuit according to claim 1, wherein the
conducting module comprises a multi-stage of stack cascaded
conducting units, and each conducting unit comprises a
transistor.
10. The RF switching circuit according to claim 9, wherein the
conducting unit comprises: a switching NMOS transistor, comprising
a drain and a source, wherein the drain is configured to receive an
RF input signal or coupled with a source of a switching NMOS
transistor in another conducting unit in the conducting module, and
the source is configured to output an RF output signal or coupled
with a drain of the switching NMOS transistor in another conducting
unit in the conducting module; or the source is configured to
receive the RF input signal or coupled with the drain of the
switching NMOS transistor in another conducting unit in the
conducting module, and the drain is configured to output the RF
output signal or coupled with a source of a switching NMOS
transistor in another conducting unit in the conducting module; a
path resistance, comprising one end coupled with the drain of the
switching NMOS transistor, and the other end coupled with the
source of the switching NMOS transistor; a gate bias resistor,
comprising one end coupled with the gate control voltage generating
module and the other end coupled with a gate of the switching NMOS
transistor; and a body bias resistor, comprising one end coupled
with the body control voltage generating module and the other end
coupled with a substrate of the switching NMOS transistor.
11. The RF switching circuit according to claim 9, wherein the
conducting unit comprises: a switching NMOS transistor, comprising
a drain and a source, wherein the drain is configured to receive an
RF input signal or coupled with a source of a switching NMOS
transistor in other conducting units in the conducting module, and
the source outputs an RF output signal or coupled with a drain of
the switching NMOS transistor in another conducting unit in the
conducting module; or the source is configured to receive the RF
input signal or coupled with the drain of the switching NMOS
transistor in other conducting units in the conducting module, and
the drain is configured to output the RF output signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module; a path resistance, comprising one
end coupled with the drain of the switching NMOS transistor, and
the other end coupled with the source of the switching NMOS
transistor; a gate bias resistor, comprising one end coupled with
the gate control voltage generating module and the other end
coupled with a gate of the switching NMOS transistor; and a body
bias diode, comprising a positive electrode coupled with a
substrate of the switching NMOS transistor and a negative electrode
coupled with the gate of the switching NMOS transistor.
12. The RF switching circuit according to claim 5, wherein the
conducting module comprises a multi-stage of stack cascaded
conducting units, and each conducting unit comprises a
transistor.
13. The RF switching circuit according to claim 12, wherein the
conducting unit comprises: a switching NMOS transistor, comprising
a drain and a source, wherein the drain is configured to receive an
RF input signal or coupled with a source of a switching NMOS
transistor in another conducting unit in the conducting module, and
the source is configured to output an RF output signal or coupled
with a drain of the switching NMOS transistor in another conducting
unit in the conducting module; or the source is configured to
receive the RF input signal or coupled with the drain of the
switching NMOS transistor in another conducting unit in the
conducting module, and the drain is configured to output the RF
output signal or coupled with a source of a switching NMOS
transistor in another conducting unit in the conducting module; a
path resistance, comprising one end coupled with the drain of the
switching NMOS transistor, and the other end coupled with the
source of the switching NMOS transistor; a gate bias resistor,
comprising one end coupled with the gate control voltage generating
module and the other end coupled with a gate of the switching NMOS
transistor; and a body bias resistor, comprising one end coupled
with the body control voltage generating module and the other end
coupled with a substrate of the switching NMOS transistor.
14. The RF switching circuit according to claim 12, wherein the
conducting unit comprises: a switching NMOS transistor, comprising
a drain and a source, wherein the drain is configured to receive an
RF input signal or coupled with a source of a switching NMOS
transistor in other conducting units in the conducting module, and
the source outputs an RF output signal or coupled with a drain of
the switching NMOS transistor in another conducting unit in the
conducting module; or the source is configured to receive the RF
input signal or coupled with the drain of the switching NMOS
transistor in other conducting units in the conducting module, and
the drain is configured to output the RF output signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module; a path resistance, comprising one
end coupled with the drain of the switching NMOS transistor, and
the other end coupled with the source of the switching NMOS
transistor; a gate bias resistor, comprising one end coupled with
the gate control voltage generating module and the other end
coupled with a gate of the switching NMOS transistor; and a body
bias diode, comprising a positive electrode coupled with a
substrate of the switching NMOS transistor and a negative electrode
coupled with the gate of the switching NMOS transistor.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Chinese
Patent Application No. 201910114122.6, filed on Feb. 14, 2019. The
entire contents of this application are hereby incorporated herein
by reference.
TECHNICAL FIELD
[0002] The present disclosure relates to the field of electrical
technology, and more particularly, to a radio frequency (RF)
switching circuit.
BACKGROUND
[0003] An RF switch is one of the control devices for controlling
an RF signal transmission path and an RF signal size, which is
widely used in many fields such as wireless communication field,
electrical countermeasures, radar systems, and electrical measuring
instruments. It is well known that a design of an RF switch
structure is critical to performance characteristics such as an
on-resistance (Ron), an off-capacitance (Coff), a Figure of Merit
(FOM), and a breakdown voltage.
[0004] In an existing RF switching circuit, the resistance of a
common bias resistor may affect circuit performances such as Ron,
Coff, FOM, and the breakdown voltage. As the resistance of the
common bias resistor increases, Ron and breakdown voltage improve,
but Coff and FOM deteriorate, which may affect an isolation and
high-frequency application of the RF switching circuit; As the
resistance of the common bias resistor decrease, Coff and FOM
improve, but Ron and the breakdown voltage deteriorate, which may
affect an insertion loss and a power capability of the RF switching
circuit.
[0005] Therefore, a new RF switching circuit is needed to improve
various performance indexes of the RF switching circuit
synthetically.
SUMMARY
[0006] The present disclosure provides an RF switching circuit,
including: a conducting module, configured to conduct an RF signal;
a gate control voltage generating module, configured to provide a
gate control voltage for the conducting module to control the
conducting module operating at ON-state or OFF-state; wherein the
gate control voltage generating module further includes: a first
resistance adaptive module, providing a first impedance in a first
state for a series branch where the conducting module and the gate
control voltage generation module locate, and a second impedance in
a second state for the series branch where the conducting module
and the gate control voltage generation module locate, wherein the
first impedance is greater than the second impedance, the first
resistance adaptive module is in the first state when the RF signal
operated by the conducting module is a high power signal or the
conducting module is turned on, and the first resistance adaptive
module is in the second state when the conducting module does not
operate the high power signal and the conducting module is turned
off.
[0007] In some embodiments, the gate control voltage generating
module further includes a first level shifter circuit and a first
filter circuit, wherein the first level shifter circuit and the
first filter circuit are respectively configured to perform a level
shifting on the first control voltage and to filter the level
shifted voltage.
[0008] In some embodiments, the first resistance adaptive module
includes: a first NOR gate, including a first input end, a second
input end and an output end, wherein the first input end is
configured to receive the first control voltage, the second input
end is configured to receive a high power enable signal, and the
output end is configured to output the resistance adaptive control
signal; a first adaptive switch, configured to receive the
resistance adaptive control signal, wherein the first adaptive
switch is configured to turn on when the resistance adaptive
control signal is high, and turn off when the resistance adaptive
control signal is low; and a first common bias resistor, coupled in
parallel with the first adaptive switch.
[0009] In some embodiments, the first resistance adaptive module
includes: a first NOR gate, including a first input end, a second
input end and an output end, wherein the first input end is
configured to receive the first control voltage, the second input
end is configured to receive a high power enable signal, and the
output end is configured to output a resistance adaptive control
signal; and a first NMOS transistor, including a gate, wherein the
gate is configured to receive the resistance adaptive control
signal.
[0010] In some embodiments, the RF switching circuit further
includes: a body control voltage generating module, configured to
provide a body control voltage for the conducting module to control
the conducting module operating at ON-state or OFF-state; wherein
the body control voltage generating module includes: a second
resistance adaptive module, in series with the conducting module to
form a series branch, and providing a first impedance for the
series branch in the first state and a second impedance for the
series branch in the second state, wherein the first impedance is
greater than the second impedance, the second resistance adaptive
module is in the first state when the RF signal operated by the
conducting module is a high power signal or the conducting module
is turned on, and the second resistance adaptive module is in the
second state when the conducting module does not operate the high
power signal and the conducting module is turned off.
[0011] In some embodiments, the body control voltage generating
module further includes a second level shifter circuit and a second
filter circuit, wherein the second level shifter circuit and the
second filter circuit are respectively configured to perform a
level shifting on the second control voltage and to filter the
level shifted voltage.
[0012] In some embodiments, the second resistance adaptive module
includes: a second NOR gate, including a first input end, a second
input end and an output end, wherein the first input end is
configured to receive a second control voltage, the second input
end is configured to receive a high power enable signal, and the
output end is configured to output the resistance adaptive control
signal; a second adaptive switch, configured to receive the
resistance adaptive control signal, wherein the second adaptive
switch turns on when the resistance adaptive control signal is
high, and turns off when the resistance adaptive control signal is
low; and a second common bias resistor, coupled in parallel with
the second adaptive switch.
[0013] In some embodiments, the second resistance adaptive module
includes: a second NOR gate, including a first input end, a second
input end and an output end, wherein the first input end is
configured to receive the second control voltage, the second input
end is configured to receive a high power enable signal, and the
output end is configured to output a resistance adaptive control
signal; and a second NMOS transistor, including a gate, wherein the
gate is configured to receive the resistance adaptive control
signal.
[0014] In some embodiments, the conducting module includes a
multi-stage of stack cascaded conducting units, and each conducting
unit includes a transistor.
[0015] In some embodiments, the conducting unit includes: a
switching NMOS transistor, including a drain and a source, wherein
the drain is configured to receive an RF input signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module, and the source is configured to
output an RF output signal or coupled with a drain of the switching
NMOS transistor in another conducting unit in the conducting
module; or the source is configured to receive the RF input signal
or coupled with the drain of the switching NMOS transistor in
another conducting unit in the conducting module, and the drain is
configured to output the RF output signal or coupled with a source
of a switching NMOS transistor in another conducting unit in the
conducting module; a path resistance, including one end coupled
with the drain of the switching NMOS transistor, and the other end
coupled with the source of the switching NMOS transistor; a gate
bias resistor, including one end coupled with the gate control
voltage generating module and the other end coupled with a gate of
the switching NMOS transistor; and a body bias resistor, including
one end coupled with the body control voltage generating module and
the other end coupled with a substrate of the switching NMOS
transistor.
[0016] In some embodiments, the conducting unit includes: a
switching NMOS transistor, including a drain and a source, wherein
the drain is configured to receive an RF input signal or coupled
with a source of a switching NMOS transistor in other conducting
units in the conducting module, and the source outputs an RF output
signal or coupled with a drain of the switching NMOS transistor in
another conducting unit in the conducting module; or the source is
configured to receive the RF input signal or coupled with the drain
of the switching NMOS transistor in other conducting units in the
conducting module, and the drain is configured to output the RF
output signal or coupled with a source of a switching NMOS
transistor in another conducting unit in the conducting module; a
path resistance, including one end coupled with the drain of the
switching NMOS transistor, and the other end coupled with the
source of the switching NMOS transistor; a gate bias resistor,
including one end coupled with the gate control voltage generating
module and the other end coupled with a gate of the switching NMOS
transistor; and a body bias diode, including a positive electrode
coupled with a substrate of the switching NMOS transistor and a
negative electrode coupled with the gate of the switching NMOS
transistor.
[0017] Embodiments of the present disclosure have the following
benefits.
[0018] In embodiments of the present disclosure, the gate control
voltage generating module includes a first resistance adaptive
module for providing a first impedance in a first state for a
series branch where the conducting module and the gate control
voltage generation module locate, and a second impedance in a
second state for the series branch where the conducting module and
the gate control voltage generation module locate, wherein the
first impedance is greater than the second impedance, the first
resistance adaptive module is in the first state when the RF signal
operated by the conducting module is a high power signal or the
conducting module is turned on, and the first resistance adaptive
module is in the second state when the conducting module does not
operate the high power signal and the conducting module is turned
off. The impedance adaptation and power control selection
introduced on the first common bias resistor improves FOM
comprehensively, and optimizes Ron, Coff, and a power breakdown
performance, which improves circuit performance and reduces
cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 schematically illustrates a structural diagram of an
existing RF switching circuit;
[0020] FIG. 2 schematically illustrates a structural diagram of an
existing RF switching circuit;
[0021] FIG. 3 schematically illustrates a structural diagram of an
RF switching circuit according to an embodiment of the present
disclosure;
[0022] FIG. 4 schematically illustrates a structural diagram of an
RF switching circuit according to an embodiment of the present
disclosure;
[0023] FIG. 5 schematically illustrates a structural diagram of an
RF switching circuit according to an embodiment of the present
disclosure; and
[0024] FIG. 6 schematically illustrates a structural diagram of an
RF switching circuit according to an embodiment of the present
disclosure.
DETAILED DESCRIPTION
[0025] Referring to FIG. 1, FIG. 1 schematically illustrates a
structural diagram of an existing RF switching circuit.
[0026] The RF switching circuit as shown in FIG. 1 includes a gate
control voltage generating module 11, a switching module 12, and a
body control voltage generating module 13, and both the gate
control voltage generating module 11 and the body control voltage
generating module 13 includes a level shifter circuit, a filter
LPF, and a common bias resistor Rc, and provide a gate control
voltage and a body control voltage for the switching module 12
respectively. The switching module 12 includes a plurality of
cascaded NMOS transistors M11, M12, M13, . . . , M1n, a plurality
of gate bias resistors Rg11, Rg12, Rg13, . . . , Rg1n, a plurality
of body bias resistors Rb11, Rb12, Rb13, . . . , Rb1n, and a
plurality of path resistors Rds11, Rds12, Rds13, . . . , Rds1n.
[0027] Referring to FIG. 2, FIG. 2 schematically illustrates a
structural diagram of an existing RF switching circuit.
[0028] Compared with the RF switching circuit shown in FIG. 1, the
RF switch circuit shown in FIG. 2 includes only a gate control
voltage generating module 21 and a switching module 22, wherein the
switch module 22 includes a plurality of cascaded NMOS transistors
M21, M22, M23, . . . , M2n, a plurality of gate bias resistors
Rg21, Rg22, Rg23, . . . , Rg2n, a plurality of via resistors Rds21,
Rds22, Rds23, . . . , Rds2n and a plurality of diodes D21, D22,
D23, . . . , D2n.
[0029] For the RF switching circuit shown in FIG. 1 and FIG. 2, as
a resistance of the common bias resistor increases, Ron and
breakdown voltage improve, but Coff and FOM deteriorate, which may
affect a isolation and high-frequency application of the RF
switching circuit; As a resistance of the common bias resistor
decrease, Coff and FOM improve, but Ron and the breakdown voltage
deteriorate, which may affect a insertion loss and a power
capability of the RF switching circuit.
[0030] Referring to FIG. 3, FIG. 3 schematically illustrates a
structural diagram of an RF switching circuit according to an
embodiment of the present disclosure.
[0031] The RF switching circuit shown in FIG. 3 includes a
conducting module, configured to conduct an RF signal; a gate
control voltage generating module 31, configured to provide a gate
control voltage for the conducting module to control the conducting
module operating at ON-state or OFF-state; and a body control
voltage generating module 33, configured to provide a body control
voltage for the conducting module to control the conducting module
operating at ON-state or OFF-state. Specifically, the body control
voltage generating module 33 assists the gate control voltage
generating module 31 to control the conducting module 32, which
improves the switching performance of the RF switching circuit.
[0032] In some embodiments, the gate control voltage generating
module 31 includes a first resistance adaptive module 311. The
first resistance adaptive module 311 provides a first impedance in
a first state for a series branch where the conducting module 32
and the gate control voltage generation module 31 locate, and a
second impedance in a second state for the series branch where the
conducting module 32 and the gate control voltage generation module
31 locate, wherein the first impedance is greater than the second
impedance, the first resistance adaptive module 311 is in the first
state when the RF signal operated by the conducting module 32 is a
high power signal or the conducting module 32 is turned on, and the
first resistance adaptive module 311 is in the second state when
the conducting module 32 does not operate the high power signal and
the conducting module is turned off.
[0033] In some embodiments, the first resistance adaptive module
311 includes a first NOR gate NOR31, a first adaptive switch S31
and a first common bias resistor Rc31.
[0034] The first NOR gate NOR31 includes a first input end, a
second input end and an output end, wherein the first input end is
configured to receive the first control voltage VCTG, the second
input end is configured to receive a high power enable HPE signal
HPE, and the output end is configured to output a resistance
adaptive control signal. The first adaptive switch S31 is
configured to receive the resistance adaptive control signal,
wherein the first adaptive switch turns on when the resistance
adaptive control signal is high, and turns off when the resistance
adaptive control signal is low. The first common bias resistor Rc31
is coupled in parallel with the first adaptive switch S31.
[0035] In some embodiments, if the conducting module 32 processes
the high power signal, the high power enable signal HPE is 1; if
the conducting module 32 does not process the high power signal,
the high power enable signal HPE is 0. When the first control
voltage VCTG is high, the conducting module 32 is turned on, and an
input value of the first input end of the first NOR gate NOR31 is
1; when the first control voltage VCTG is low, the conducting
module 32 is turned off, and the input value of the first input end
of the first NOR gate NOR 31 is 0.
[0036] Therefore, the resistance adaptive control signal output
from the first NOR gate NOR31 in the first state is a low level,
the first adaptive switch S31 is turned on, the first common bias
resistor Rc31 is connected to the circuit, and the first resistance
adaptive module 311 provides a first impedance for a series branch
where the conducting module 32 and the gate control voltage
generating module 31 locate; the resistance adaptive control signal
output from the first NOR gate NOR31 in the first state is a high
level, the first adaptive switch S31 is turned off, the first
common bias resistor Rc31 is shorted, and the first resistance
adaptive module 311 provides a second impedance for a series branch
where the conducting module 32 and the gate control voltage
generating module 31 locate. The first impedance is greater than
the second impedance.
[0037] In some embodiments, the RF switching circuit needs to
conduct the RF signal when the conducting module 32 is turned on,
which requires a low insertion loss, in other words, a low
on-resistance; and the RF signal needs to isolate the RF signal
when the conducting module 32 is turned off, which requires a low
truncating capacitor. It should be noted that, when the high power
enable signal HPE is 1, the conducting module 32 is in an off
state, but the first resistance adaptive module 311 is still
required to provide a high first impedance due to the need to
isolate the high power signals of the other branches.
[0038] Based on the above design, when the RF switching circuit
processes the high power signal, the first common bias resistor
Rc31 is connected to the circuit to meet a breakdown voltage
requirement of the circuit in high power applications; when the
conducting module 32 is turned on, the first common bias resistor
Rc31 is connected to the circuit to meet the requirement of the
circuit for a low Ron when the RF switch is turned on; when the
conducting module 32 is turned off, the first common bias resistor
Rc31 is shorted to meets the requirement of the circuit for a low
Coff when the RF switch is turned off, which improves the FOM of
the circuit.
[0039] In some embodiments, the gate control voltage generating
module 31 further includes a first level shifter circuit 312 and a
first filter circuit 313, wherein the first level shifter circuit
and the first filter circuit are respectively configured to perform
a level shifting on the first control voltage and to filter the
level shifted voltage.
[0040] In some embodiments, similar to the gate control voltage
generating module 31, the body control voltage generating module 33
is configured to provide a body control voltage for the conducting
module 32 to control the conducting module 32 operating at ON-state
or OFF-state, and includes: a second resistance adaptive module
331, in series with the conducting module 32 to form a serious
branch, and providing a first impedance for the series branch in
the first state and a second impedance for the series branch in the
second state, wherein the first impedance is greater than the
second impedance, the second resistance adaptive module 331 is in
the first state when the RF signal operated by the conducting
module is a high power signal or the conducting module is turned
on, and the second resistance adaptive module 331 is in the second
state when the conducting module does not operate the high power
signal and the conducting module is turned off.
[0041] Specifically, the second resistance adaptive module 331
includes: a second NOR gate NOR32, a second adaptive switch S32,
and a second common bias resistor Rc32.
[0042] In some embodiments, the second NOR gate NOR 32 includes a
first input end configured to receive a second control voltage
VCTB, a second input end configured to receive the high power
enable signal HPE, and an output end outputting a resistance
adaptive control signal. The second adaptive switch S32 is
configured to receive the resistance adaptive control signal, and
turns on when the resistance adaptive control signal is at a high
level, so the second common bias resistor Rc32 is shorted; the
second adaptive switch S32 turns off when the resistance adaptive
control signal is at a low level, so the second common bias
resistor Rc32 is connected to the circuit. For more details about
the second resistance adaptive module 331, reference may be made to
the related description of the first resistance adaptive module
311, which is not described herein.
[0043] In some embodiments, the body control voltage generating
module 33 further includes a second level shifter circuit 332 and a
second filter circuit 333, wherein the second level shifter circuit
332 and the second filter circuit 333 are respectively configured
to perform a level shifting on the second control voltage and to
filter the level shifted voltage.
[0044] In some embodiments, the conducting module 32 includes a
multi-stage of stack cascaded conducting units, and each conducting
unit includes a transistor. Specifically, the transistor may be an
NMOS transistor.
[0045] In some embodiments, the conducting module 32 includes a
plurality of switching NOMS transistor (M31-M3n), a plurality of
gate bias resistors (Rg31-Rg3n), a plurality of body bias resistors
(Rb31-Rb3n), and a plurality of path resistors (Rds31-Rds3n).
[0046] In some embodiments, each conducting unit includes: a
switching NMOS transistor, including a drain and a source, wherein
the drain is configured to receive an RF input signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module 32, and the source is configured to
output an RF output signal or coupled with a drain of the switching
NMOS transistor in another conducting unit in the conducting module
32; in some embodiments, the source is configured to receive the RF
input signal or coupled with the drain of the switching NMOS
transistor in other conducting units in the conducting module, and
the drain is configured to output the RF output signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module.
[0047] Each conducting unit further includes: a path resistance,
including one end coupled with the drain of the switching NMOS
transistor, and the other end coupled with the source of the
switching NMOS transistor; a gate bias resistor, including one end
coupled with the gate control voltage generating module 31 and the
other end coupled with a gate of the switching NMOS transistor; and
a body bias resistor, including one end coupled with the body
control voltage generating module 33 and the other end coupled with
a substrate of the switching NMOS transistor.
[0048] Referring to FIG. 4, FIG. 4 schematically illustrates a
structural diagram of an RF switching circuit according to an
embodiment of the present disclosure.
[0049] The RF switching circuit shown in FIG. 4 includes a gate
control voltage generating module 41, a conducting module 42 and a
body control voltage generating module 43. The gate control voltage
generating module 41 includes a first resistance adaptive module
411, a first level shifter circuit 412, and a first filter circuit
413. The body control voltage generating module 43 includes a
second resistance adaptive module 431, a second level shifter
circuit 432, and a second filter circuit 433.
[0050] In some embodiments, the conducting module 32 includes a
multi-stage of stack cascaded conducting units, and each conducting
unit includes a transistor. Specifically, the transistor may be an
NMOS transistor.
[0051] In some embodiments, the conducting module 42 includes a
plurality of NOMS tubes (M41-M4n), a plurality of gate bias
resistors (Rg41-Rg4n), a plurality of body bias resistors
(Rb41-Rb4n), and a plurality of path resistance (Rds41-Rds4n). For
more details about the conducting unit in the conducting module 42,
reference may be made to the above description of the conducting
unit in the conducting module 32, and details are not described
herein.
[0052] Compared with the RF switching circuit shown in FIG. 3, in
the RF switching circuit shown in FIG. 4, the first resistance
adaptive module 411 includes: a first NOR gate NOR41, including a
first input end, a second input end and an output end, wherein the
first input end is configured to receive the first control voltage,
the second input end is configured to receive a high power enable
signal, and the output end is configured to output a resistance
adaptive control signal; and a first NMOS transistor Mc41,
including a gate, wherein the gate is configured to receive the
resistance adaptive control signal.
[0053] In some embodiments, if the conducting module 42 processes
the high power signal, the high power enable signal HPE is 1; if
the conducting module 42 does not process the high power signal,
the high power enable signal HPE is 0. When the first control
voltage VCTG is high, the conducting module 42 is turned on, and an
input value of the first input end of the first NOR gate NOR31 is
1; when the first control voltage VCTG is low, the conducting
module 42 is turned off, and the input value of the first input end
of the first NOR gate NOR 31 is 0.
[0054] Therefore, the resistance adaptive control signal output
from the first NOR gate NOR41 in the first state is a low level,
the first NMOS transistor Mc41 is in a cutoff state, and the first
resistance adaptive module 411 provides a first impedance for a
series branch where the conducting module 42 and the gate control
voltage generating module 41 locate; the resistance adaptive
control signal output from the first NOR gate NOR31 in the first
state is a high level, the first NMOS transistor Mc41 is in a
conducting state, and the first resistance adaptive module 411
provides a second impedance for a series branch where the
conducting module 42 and the gate control voltage generating module
41 locate. The first impedance is greater than the second
impedance.
[0055] Therefore, in the embodiment, when the RF switching circuit
processes the high power signal, the first NMOS transistor Mc41 is
in the cutoff state, which is equivalent to a large resistance to
meet a breakdown voltage requirement of the circuit in high power
applications; when the conducting module 42 is turned on, the first
NMOS transistor Mc41 is in the cutoff state, which is equivalent to
a large resistance to meet the requirement of the circuit for a low
Ron when the RF switch is turned on; when the conducting module 42
is turned off, the first NMOS transistor Mc41 is in the conducting
state, which is equivalent to a large resistance, to meet the
requirement of the circuit for a low Coff when the RF switch is
turned off, which improves the FOM of the circuit.
[0056] In some embodiments, the second resistance adaptive module
431 includes: a second NOR gate NOR42, including a first input end
for receiving the second control voltage VCTB, and a second input
end for receiving the high power enable signal HPE, and an output
end for outputting a resistance adaptive control signal; and a
second NMOS transistor Mc42 including a gate for receiving the
resistance adaptive control signal.
[0057] In some embodiments, the second NMOS transistor Mc42 is
configured to receive the resistance adaptive control signal, and
is in the conducting state when the resistance adaptive control
signal is at a high level, and is in the cutoff state when the
resistance adaptive control signal is at a low level. For more
details about the second resistance adaptive module 431, reference
may be made to the related description of the first resistance
adaptive module 411, and details are not described herein
again.
[0058] Referring to FIG. 5, FIG. 5 schematically illustrates a
structural diagram of an RF switching circuit according to an
embodiment of the present disclosure.
[0059] Compared with the RF switching circuit shown in FIG. 4, the
RF switching circuit shown in FIG. 5 only includes the gate control
voltage generating module 51 and the conducting module 52. The gate
control voltage generating module 51 includes a first resistance
adaptive module 511, a first level shifter circuit 512, and a first
filter circuit 513.
[0060] In some embodiments, the gate control voltage generating
module 51 includes a first resistance adaptive module 511, a first
level shifter circuit 512, and a first filter circuit 513. For more
details about the gate control voltage generating module 51,
reference may be made to the related description of the gate
control voltage generating module 41, and details are not described
herein again.
[0061] In some embodiments, the conducting module 52 includes a
multi-stage of stack cascaded conducting units, and each conducting
units includes a transistor. Specifically, the transistor may be an
NMOS transistor.
[0062] In some embodiments, the conducting module 52 includes a
plurality of NOMS tubes (M51-M5n), a plurality of gate bias
resistors (Rg51-Rg5n), a plurality of body bias diodes (D51-D5n),
and a plurality of path resistance (Rds51-Rds5n).
[0063] In some embodiments, each conducting unit includes: a
switching NMOS transistor, including a drain and a source, wherein
the drain is configured to receive an RF input signal or coupled
with a source of a switching NMOS transistor in another conducting
unit in the conducting module 52, and the source is configured to
output an RF output signal or coupled with a drain of the switching
NMOS transistor in another conducting unit in the conducting module
52; or the source is configured to receive the RF input signal or
coupled with the drain of the switching NMOS transistor in other
conducting units in the conducting module, and the drain is
configured to output the RF output signal or coupled with a source
of a switching NMOS transistor in another conducting unit in the
conducting module; a path resistance, including one end coupled
with the drain of the switching NMOS transistor, and the other end
coupled with the source of the switching NMOS transistor; a gate
bias resistor, including one end coupled with the gate control
voltage generating module 51 and the other end coupled with a gate
of the switching NMOS transistor; and a body bias diode, including
a positive electrode coupled with a substrate of the switching NMOS
transistor and a negative electrode coupled with the gate of the
switching NMOS transistor.
[0064] Referring to FIG. 6, FIG. 6 schematically illustrates a
structural diagram of an RF switching circuit according to an
embodiment of the present disclosure.
[0065] As shown in FIG. 6, compared with the existing technology,
the technical solution provided by the embodiment of the present
disclosure can improve Coff while maintaining Ron, and can improve
Ron while maintaining Coff. Therefore, the FOM may be
comprehensively improved by 15%, which optimizes circuit
performance and reduces costs.
[0066] Although the present disclosure has been disclosed above
with reference to preferred embodiments thereof, it should be
understood that the disclosure is presented by way of example only,
and not limitation. Those skilled in the art may modify and vary
the embodiments without departing from the spirit and scope of the
present disclosure.
* * * * *