U.S. patent application number 16/987539 was filed with the patent office on 2021-11-18 for radio-frequency switching circuit with damage detection of dc blocking capacitor.
This patent application is currently assigned to Samsung Electro-Mechanics Co., Ltd.. The applicant listed for this patent is Samsung Electro-Mechanics Co., Ltd.. Invention is credited to Jong Myeong KIM, Ju Young PARK.
Application Number | 20210359711 16/987539 |
Document ID | / |
Family ID | 1000005941013 |
Filed Date | 2021-11-18 |
United States Patent
Application |
20210359711 |
Kind Code |
A1 |
KIM; Jong Myeong ; et
al. |
November 18, 2021 |
RADIO-FREQUENCY SWITCHING CIRCUIT WITH DAMAGE DETECTION OF DC
BLOCKING CAPACITOR
Abstract
A radio-frequency switching circuit includes a first switching
circuit connected between a common capacitor connected to an
antenna port and a first capacitor connected to a first port, and
performing a switching operation with a first gate voltage
transmitted through a first gate terminal, a voltage generation
circuit supplying a drain-source voltage to a common node disposed
at a first end of the first switching circuit, and a voltage
detection circuit receiving a node voltage from the common node,
comparing the node voltage with a reference voltage, and generating
a detection voltage including damage information regarding the
common capacitor or the first capacitor.
Inventors: |
KIM; Jong Myeong; (Suwon-si,
KR) ; PARK; Ju Young; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electro-Mechanics Co., Ltd. |
Suwon-si |
|
KR |
|
|
Assignee: |
Samsung Electro-Mechanics Co.,
Ltd.
Suwon-si
KR
|
Family ID: |
1000005941013 |
Appl. No.: |
16/987539 |
Filed: |
August 7, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04B 1/44 20130101; H04B
1/0078 20130101 |
International
Class: |
H04B 1/00 20060101
H04B001/00; H04B 1/44 20060101 H04B001/44 |
Foreign Application Data
Date |
Code |
Application Number |
May 15, 2020 |
KR |
10-2020-0058358 |
Claims
1. A radio-frequency switching circuit comprising: a first
switching circuit, connected between a common capacitor connected
to an antenna port and a first capacitor connected to a first port,
and configured to perform a switching operation with a first gate
voltage transmitted through a first gate terminal; a voltage
generation circuit, configured to supply a drain-source voltage to
a common node disposed at a first end of the first switching
circuit; and a voltage detection circuit configured to receive a
node voltage from the common node, compare the received node
voltage with a reference voltage, and generate a detection voltage
including damage information regarding one or more of the common
capacitor and the first capacitor.
2. The radio-frequency switching circuit of claim 1, further
comprising: a first logic circuit, configured to control a level of
the first gate voltage of the first switching circuit, based on the
detection voltage; and a first drain-source (DS) resistor connected
between the common node and a second end of the first switching
circuit.
3. The radio-frequency switching circuit of claim 2, wherein the
voltage detection circuit comprises a comparator, configured to
output the detection voltage having a first level when the node
voltage is higher than the reference voltage, and configured to
output the detection voltage having a second level when the node
voltage is lower than the reference voltage.
4. The radio-frequency switching circuit of claim 1, wherein the
drain-source voltage is lower than a high level of the first gate
voltage, and higher than a low level of the first gate voltage.
5. The radio-frequency switching circuit of claim 1, wherein the
radio-frequency switching circuit further comprises at least a
second switching circuit among the second switching circuit to an
n-th switching circuit, where n is a natural number of 2 or more,
wherein the second switching circuit is connected between the
common capacitor and a second capacitor connected to a second port,
and the second switching circuit is configured to perform a
switching operation with a second gate voltage supplied through a
second gate terminal, and wherein the n-th switching circuit is
connected between the common capacitor and an n-th capacitor
connected to an n-th port, and the n-th switching circuit is
configured to perform a switching operation with an n-th gate
voltage supplied through an n-th gate terminal.
6. The radio-frequency switching circuit of claim 1, wherein the
first logic circuit comprises a first AND gate, configured to
perform a logical product operation on the detection voltage and a
first control voltage to generate the first gate voltage, and
output the generated first gate voltage to the first gate
terminal.
7. The radio-frequency switching circuit of claim 1, further
comprising a first bypass shunt circuit connected between the first
end end or a second end of the first switching circuit and a
ground, and configured to perform a switching operation based on
the detection voltage.
8. The radio-frequency switching circuit of claim 7, wherein the
first bypass shunt circuit comprises a plurality of transistors
stacked in series with each other, and configured to perform a
switching operation based on the detection voltage.
9. A radio-frequency switching circuit comprising: first to n-th
switching circuits connected to a common node in parallel to each
other, the common node being connected to a common capacitor, where
n is a natural number of 2 or more; a voltage generation circuit,
configured to supply a drain-source voltage to the common node; a
voltage detection circuit, configured to receive a node voltage
from the common node, and compare the received node voltage with a
reference voltage to generate a detection voltage including damage
information regarding a direct current (DC) blocking capacitor
including the common capacitor; and first to n-th logic circuits,
configured to control voltage levels of the first to n-th gate
voltages of the first to n-th switching circuits, respectively,
based on the detection voltage.
10. The radio-frequency switching circuit of claim 9, wherein the
first switching circuit is connected between the common capacitor
and a first capacitor connected to a first port, and is configured
to perform a switching operation with a first gate voltage supplied
through a first gate terminal, and the n-th switching circuit is
connected between the common capacitor and an n-th capacitor
connected to an n-th port, and is configured to perform a switching
operation with an n-th gate voltage supplied through an n-th gate
terminal.
11. The radio-frequency switching circuit of claim 9, further
comprising first to n-th DS resistors connected between a first end
and a second end of the first to n-th switching circuits,
respectively.
12. The radio-frequency switching circuit of claim 9, wherein the
voltage detection circuit comprises a comparator configured to
output a detection voltage having a first level when the node
voltage is higher than the reference voltage, and configured to
output the detection voltage having a second level when the node
voltage is lower than the reference voltage.
13. The radio-frequency switching circuit of claim 9, wherein the
drain-source voltage is a voltage lower than a high level of the
first gate voltage, and higher than a low level of the first gate
voltage.
14. The radio-frequency switching circuit of claim 9, wherein the
first logic circuit comprises a first AND gate, configured to
perform a logical product operation on the detection voltage and a
first control voltage to generate the first gate voltage and output
the first gate voltage to the first gate terminal, and the n-th
logic circuit comprises an n-th AND gate, configured to perform a
logical product operation on the detection voltage and an n-th
control voltage to generate the n-th gate voltage and output the
n-th gate voltage to the n-th gate terminal.
15. The radio-frequency switching circuit of claim 14, further
comprising a first bypass shunt circuit to an n-th bypass shunt
circuit, wherein the first bypass shunt circuit is connected
between a first end or a second end of the first switching circuit
and a ground, and is configured to perform a switching operation
based on the detection voltage, and the n-th bypass shunt circuit
is connected between the first end or the second end of the n-th
switching circuit and the ground, and is configured to perform a
switching operation based on the detection voltage.
16. The radio-frequency switching circuit of claim 15, wherein the
first bypass shunt circuit comprises a plurality of transistors
stacked with each other in series, and is configured to perform a
switching operation based on the detection voltage, and the n-th
bypass shunt circuit comprises a plurality of transistors stacked
in series with each other, and configured to perform a switching
operation based on the detection voltage.
17. A communication terminal comprising: a radio-frequency
switching circuit comprising: a switching circuit connected between
a common capacitor and a first capacitor; a voltage generator
circuit, configured to supply a drain-source voltage to a common
node; a comparator, configured to compare a node voltage from the
common node with a reference voltage, and generate a detection
voltage including operational information related to the common
capacitor or the first capacitor; and a bypass shunt circuit
configured to perform a switching operation based on the detection
voltage.
18. The communication terminal of claim 17, wherein the operational
information is determined based on a level of the node voltage.
19. The communication terminal of claim 17, wherein the operational
information indicates whether one or more of the common capacitor
and the first capacitor is damaged.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit under 35 USC .sctn.
119(a) of Korean Patent Application No. 10-2020-0058358 filed on
May 15, 2020 in the Korean Intellectual Property Office, the entire
disclosure of which is incorporated herein by reference for all
purposes.
BACKGROUND
1. Field
[0002] The following description relates to a radio-frequency
switching circuit with a damage detecting DC blocking
capacitor.
2. Description of Related Art
[0003] Typically, wireless communication terminals may include a
radio-frequency switching circuit that switches a transmission (TX)
signal and a reception (RX) signal between antennas and a plurality
of ports.
[0004] Typically, a radio-frequency switching circuit may include
one series switch, but may usually include a plurality of series
switches, and each of the plurality of series switches may include
a plurality of transistors (e.g., FETs) connected to each other in
series.
[0005] In the example of existing radio-frequency switching
circuits, in order to achieve stable operations of a transmission
(Tx) mode power amplifier, as well as to improve basic
characteristics of the switch (e.g., insertion loss, isolation,
linearity, etc.), a negative voltage may be supplied to gates of a
plurality of transistors included in the switch.
[0006] To generate such a negative voltage, an additional circuit
such as a charge pump and an oscillator may be necessary. This
increases not only the chip area, but may also take a long time to
drive, resulting in a relatively long switching time period and
additional current consumption.
[0007] To solve this existing disadvantage, typical radio-frequency
switching circuits may have a structure that obtains an effect of
providing a drain-source voltage (Vds) (e.g., 2.5V), which is a
voltage higher than 0V, to a signal node to which sources or drains
of a plurality of transistors are connected, and may supply a
negative voltage to a gate terminal when a gate voltage supplied to
gates of the plurality of transistors is 0V.
[0008] As described above, the radio-frequency switching circuit
that uses the drain-source voltage, may supply the drain-source
voltage (Vds) to the signal node, such that a capacitor blocking
the DC voltage at each port may be connected.
[0009] However, when the capacitor is damaged by a high voltage
(e.g., destruction by a static voltage), the DC voltage cannot be
blocked, and thus, an improvement due to the use of the negative
voltage, may not be achieved, which may particularly affect the
linearity characteristic, and substantially deteriorate performance
during an operation in the Tx mode.
[0010] To address this problem, it may be necessary to detect that
the capacitor is broken or damaged.
SUMMARY
[0011] This Summary is provided to introduce a selection of
concepts in simplified form that are further described below in the
Detailed Description. This Summary is not intended to identify key
features or essential features of the claimed subject matter, nor
is it intended to be used as an aid in determining the scope of the
claimed subject matter.
[0012] In a general aspect, a radio-frequency switching circuit
includes a first switching circuit, connected between a common
capacitor connected to an antenna port and a first capacitor
connected to a first port, and configured to perform a switching
operation with a first gate voltage transmitted through a first
gate terminal, a voltage generation circuit, configured to supply a
drain-source voltage to a common node disposed at a first end of
the first switching circuit; and a voltage detection circuit
configured to receive a node voltage from the common node, compare
the received node voltage with a reference voltage, and generate a
detection voltage including damage information regarding one or
more of the common capacitor and the first capacitor.
[0013] The radio-frequency switching circuit may include a first
logic circuit, configured to control a level of the first gate
voltage of the first switching circuit, based on the detection
voltage; and a first drain-source (DS) resistor connected between
the common node and a second end of the first switching
circuit.
[0014] The voltage detection circuit may include a comparator,
configured to output the detection voltage having a first level
when the node voltage is higher than the reference voltage, and
configured to output the detection voltage having a second level
when the node voltage is lower than the reference voltage.
[0015] The drain-source voltage may be lower than a high level of
the first gate voltage, and higher than a low level of the first
gate voltage.
[0016] The radio-frequency switching circuit may further include at
least a second switching circuit among the second switching circuit
to an n-th switching circuit, where n is a natural number of 2 or
more, wherein the second switching circuit may be connected between
the common capacitor and a second capacitor connected to a second
port, and the second switching circuit may be configured to perform
a switching operation with a second gate voltage supplied through a
second gate terminal, and wherein the n-th switching circuit may be
connected between the common capacitor and an n-th capacitor
connected to an n-th port, and the n-th switching circuit may be
configured to perform a switching operation with an n-th gate
voltage supplied through an n-th gate terminal.
[0017] The first logic circuit may include a first AND gate,
configured to perform a logical product operation on the detection
voltage and a first control voltage to generate the first gate
voltage, and output the generated first gate voltage to the first
gate terminal.
[0018] The radio-frequency switching circuit may further include a
first bypass shunt circuit connected between the first end end or a
second end of the first switching circuit and a ground, and
configured to perform a switching operation based on the detection
voltage.
[0019] The first bypass shunt circuit may include a plurality of
transistors stacked in series with each other, and configured to
perform a switching operation based on the detection voltage.
[0020] In a general aspect, a radio-frequency switching circuit
includes first to n-th switching circuits connected to a common
node in parallel to each other, the common node being connected to
a common capacitor, where n is a natural number of 2 or more; a
voltage generation circuit, configured to supply a drain-source
voltage to the common node; a voltage detection circuit, configured
to receive a node voltage from the common node, and compare the
received node voltage with a reference voltage to generate a
detection voltage including damage information regarding a direct
current (DC) blocking capacitor including the common capacitor; and
first to n-th logic circuits, configured to control voltage levels
of the first to n-th gate voltages of the first to n-th switching
circuits, respectively, based on the detection voltage.
[0021] The first switching circuit may be connected between the
common capacitor and a first capacitor connected to a first port,
and may be configured to perform a switching operation with a first
gate voltage supplied through a first gate terminal, and the n-th
switching circuit may be connected between the common capacitor and
an n-th capacitor connected to an n-th port, and is configured to
perform a switching operation with an n-th gate voltage supplied
through an n-th gate terminal.
[0022] The radio-frequency switching circuit may further include
first to n-th DS resistors connected between a first end and a
second end of the first to n-th switching circuits,
respectively.
[0023] The voltage detection circuit may include a comparator
configured to output a detection voltage having a first level when
the node voltage is higher than the reference voltage, and
configured to output the detection voltage having a second level
when the node voltage is lower than the reference voltage.
[0024] The drain-source voltage may be a voltage lower than a high
level of the first gate voltage, and higher than a low level of the
first gate voltage.
[0025] The first logic circuit may include a first AND gate,
configured to perform a logical product operation on the detection
voltage and a first control voltage to generate the first gate
voltage and output the first gate voltage to the first gate
terminal, and the n-th logic circuit may include an n-th AND gate,
configured to perform a logical product operation on the detection
voltage and an n-th control voltage to generate the n-th gate
voltage and output the n-th gate voltage to the n-th gate
terminal.
[0026] The radio-frequency switching circuit may include a first
bypass shunt circuit to an n-th bypass shunt circuit, wherein the
first bypass shunt circuit may be connected between a first end or
a second end of the first switching circuit and a ground, and may
be configured to perform a switching operation based on the
detection voltage, and the n-th bypass shunt circuit is connected
between the first end or the second end of the n-th switching
circuit and the ground, and may be configured to perform a
switching operation based on the detection voltage.
[0027] The first bypass shunt circuit may include a plurality of
transistors stacked with each other in series, and may be
configured to perform a switching operation based on the detection
voltage, and the n-th bypass shunt circuit may include a plurality
of transistors stacked in series with each other, and may be
configured to perform a switching operation based on the detection
voltage.
[0028] In a general aspect, a communication terminal includes a
radio-frequency switching circuit includes a switching circuit
connected between a common capacitor and a first capacitor; a
voltage generator circuit, configured to supply a drain-source
voltage to a common node; a comparator, configured to compare a
node voltage from the common node with a reference voltage, and
generate a detection voltage including damage information related
to the common capacitor or the first capacitor; and a bypass shunt
circuit configured to perform a switching operation based on the
detection voltage.
[0029] The damage information may be determined based on a level of
the node voltage.
[0030] The operational information may indicate whether one or more
of the common capacitor and the first capacitor is damaged.
[0031] Other features and aspects will be apparent from the
following detailed description, the drawings, and the claims.
BRIEF DESCRIPTION OF DRAWINGS
[0032] FIG. 1 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0033] FIG. 2 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0034] FIG. 3 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0035] FIG. 4 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0036] FIG. 5 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0037] FIG. 6 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0038] FIG. 7 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments.
[0039] FIG. 8 illustrates an example voltage detection circuit, in
accordance with one or more embodiments.
[0040] FIG. 9 is a graph illustrating input power-insertion loss
depending on whether a DC drain-source voltage is supplied or not,
in accordance with one or more embodiments.
[0041] Throughout the drawings and the detailed description, unless
otherwise described or provided, the same drawing reference
numerals will be understood to refer to the same elements,
features, and structures. The drawings may not be to scale, and the
relative size, proportions, and depiction of elements in the
drawings may be exaggerated for clarity, illustration, and
convenience.
DETAILED DESCRIPTION
[0042] The following detailed description is provided to assist the
reader in gaining a comprehensive understanding of the methods,
apparatuses, and/or systems described herein. However, various
changes, modifications, and equivalents of the methods,
apparatuses, and/or systems described herein will be apparent to
one of ordinary skill in the art. For example, the sequences of
operations described herein are merely examples, and are not
limited to those set forth herein, but may be changed as will be
apparent after an understanding of the disclosure of this
application, with the exception of operations necessarily occurring
in a certain order. Also, descriptions of features that are known
in the art may be omitted for increased clarity and
conciseness.
[0043] The features described herein may be embodied in different
forms, and are not to be construed as being limited to the examples
described herein. Rather, the examples described herein have been
provided so that this disclosure will be thorough and complete, and
will fully convey the scope of the disclosure to one of ordinary
skill in the art.
[0044] Herein, it is noted that use of the term "may" with respect
to an embodiment or example, e.g., as to what an embodiment or
example may include or implement, means that at least one
embodiment or example exists in which such a feature is included or
implemented while all examples and examples are not limited
thereto.
[0045] Throughout the specification, when an element, such as a
layer, region, or substrate, is described as being "on," "connected
to," or "coupled to" another element, it may be directly "on,"
"connected to," or "coupled to" the other element, or there may be
one or more other elements intervening therebetween. In contrast,
when an element is described as being "directly on," "directly
connected to," or "directly coupled to" another element, there can
be no other elements intervening therebetween.
[0046] As used herein, the term "and/or" includes any one and any
combination of any two or more of the associated listed items.
[0047] Although terms such as "first," "second," and "third" may be
used herein to describe various members, components, regions,
layers, or sections, these members, components, regions, layers, or
sections are not to be limited by these terms. Rather, these terms
are only used to distinguish one member, component, region, layer,
or section from another member, component, region, layer, or
section. Thus, a first member, component, region, layer, or section
referred to in examples described herein may also be referred to as
a second member, component, region, layer, or section without
departing from the teachings of the examples.
[0048] Spatially relative terms such as "above," "upper," "below,"
and "lower" may be used herein for ease of description to describe
one element's relationship to another element as illustrated in the
figures. Such spatially relative terms are intended to encompass
different orientations of the device in use or operation in
addition to the orientation depicted in the figures. For example,
if the device in the figures is turned over, an element described
as being "above" or "upper" relative to another element will then
be "below" or "lower" relative to the other element. Thus, the term
"above" encompasses both the above and below orientations depending
on the spatial orientation of the device. The device may also be
oriented in other ways (for example, rotated 90 degrees or at other
orientations), and the spatially relative terms used herein are to
be interpreted accordingly.
[0049] The terminology used herein is for describing various
examples only, and is not to be used to limit the disclosure. The
articles "a," "an," and "the" are intended to include the plural
forms as well, unless the context clearly indicates otherwise. The
terms "comprises," "includes," and "has" specify the presence of
stated features, numbers, operations, members, elements, and/or
combinations thereof, but do not preclude the presence or addition
of one or more other features, numbers, operations, members,
elements, and/or combinations thereof.
[0050] Due to manufacturing techniques and/or tolerances,
variations of the shapes illustrated in the drawings may occur.
Thus, the examples described herein are not limited to the specific
shapes illustrated in the drawings, but include changes in shape
that occur during manufacturing.
[0051] The features of the examples described herein may be
combined in various ways as will be apparent after an understanding
of the disclosure of this application. Further, although the
examples described herein have a variety of configurations, other
configurations are possible as will be apparent after an
understanding of the disclosure of this application.
[0052] The drawings may not be to scale, and the relative sizes,
proportions, and depiction of elements in the drawings may be
exaggerated for clarity, illustration, and convenience.
[0053] FIG. 1 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments, and FIG. 2
illustrates an example radio-frequency switching circuit according
to another example, in accordance with one or more embodiments.
[0054] Referring to FIGS. 1 and 2, a radio-frequency switching
circuit 10, in accordance with one or more embodiments, may include
a first switching circuit SE1, a voltage generation circuit 50, and
a voltage detection circuit 100.
[0055] Additionally, the radio-frequency switching circuit may
include a first drain-to-source (DS) resistor Rds1.
[0056] In an example, the first switching circuit SE1 may be
connected between a common capacitor, Ccom, connected to an antenna
port P.sub.ant and a first capacitor Cp1 connected to a first port
P1, and may perform a switching operation with a first gate voltage
Vg1a supplied through a first gate terminal TGE1. In an example, an
antenna ANT may be connected to the antenna port P.sub.ant, and a
transmission circuit or a reception circuit may be connected to the
first port P1.
[0057] The voltage generation circuit 50 may supply a drain-source
voltage Vds to a common node Ncom.
[0058] The voltage detection circuit 100 may receive a node voltage
Vnd from the common node Ncom, may compare the node voltage Vnd to
a reference voltage Vref, and may generate a detection voltage Vd
including operational information or deterioration information or
damage information regarding an operational state or a performance
state of the common capacitor Ccom or the first capacitor Cp1. In
an example, damage to the common capacitor Ccom or the first
capacitor Cp1 may mean or refer to a loss of function, such as
destruction of the common capacitor Ccom or the first capacitor
Cp1, and when destroyed, the signal node may be connected to
ground, so that the direct current (DC) voltage of the signal node
may have a ground level.
[0059] In an example, the drain-source voltage Vds may be lower
than a high level of the first gate voltage Vg1a and higher than a
low level of the first gate voltage Vg1a. For example, when the
high-level voltage of the first gate voltage Vg1a is 5V and the low
level voltage of the first gate voltage Vg1a is 0V, the
drain-source voltage Vds may be a voltage lower than 5V and higher
than 0V, and for example, may have a value of 2.5V.
[0060] To block a DC of the drain-source voltage Vds, the common
capacitor Ccom and the first capacitor Cp1 connected to both ends
of the first switching circuit SE1, may be included.
[0061] The common capacitor Ccom is connected between the antenna
port P.sub.ant and the first switching circuit SE1, and the first
capacitor Cp1 is connected between the first switching circuit SE1
and the first port P1.
[0062] The first DS resistor Rds1 is connected between the common
node Ncom and a second end N1 of the first switching circuit SE1.
In an example, the first DS resistor Rds1 is connected between both
ends of the first switching circuit SE1, to enable the drain-source
voltage Vds to be applied to both ends of the first switching
circuit SE1.
[0063] Referring to FIG. 2, the radio-frequency switching circuit
10 may further include a first logic circuit 200-1 in addition to
the radio-frequency switching circuit 10 of FIG. 1.
[0064] The first logic circuit 200-1 may control a level of the
first gate voltage Vg1a supplied to the gate terminal TGE1 of the
first switching circuit SE1, based on the detection voltage Vd and
a received first control voltage Vg1S.
[0065] For respective drawings of the present examples, unnecessary
duplicate descriptions may be omitted for the same reference
numerals and components having the same function, and details of
differences for the drawings may be described.
[0066] FIG. 3 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments, and FIG. 4
illustrates an example radio-frequency switching circuit, in
accordance with one or more embodiments.
[0067] The radio-frequency switching circuit illustrated in FIGS. 3
and 4 may further include a first bypass shunt circuit 300-1 in
addition to the radio-frequency switching circuit 10 of FIG. 1.
[0068] The radio-frequency switching circuit illustrated in FIG. 4
may further include a first logic circuit 200-1 in the
radio-frequency switching circuit of FIG. 3.
[0069] Referring to FIGS. 3 and 4, the first bypass shunt circuit
300-1 is connected between a first end or a second end of the first
switching circuit SE1 and a ground, and may perform a switching
operation based on the detection voltage Vd.
[0070] In an example, when the voltage detection circuit 100
determines or detects a problem with the common capacitor Ccom or
the first capacitor Cp1 by checking the state of the drain-source
voltage based on the node voltage Vnd, the voltage detection
circuit 100 may turn on the first bypass shunt circuit 300-1, to
bypass a signal through the signal path of the first switching
circuit SE1 to the ground. The first logic circuit 200-1 may supply
the first gate voltage Vg1a, of which the level is adjusted, to the
first switching circuit SE1, based on the detection voltage Vd and
the input first control voltage Vg1s.
[0071] In an example, the first switching circuit SE1 may include a
plurality of transistors ME1, ME2 and ME3 connected to each other
in series. Although only three transistors are illustrated, this is
only an example, and the number of transistors may be more or less
than three, based on the examples. The plurality of transistors
ME1, ME2 and ME3 may receive the first gate voltage Vg1a of which
the level has been regulated through gate resistors RG1, RG2 and
RG3 connected to the respective gates of the transistors ME1, ME2
and ME3.
[0072] In an example, the first bypass shunt circuit 300-1 may
include a plurality of transistors MH, MH2 and MH3 connected to
each other in series. Although only three transistors are
illustrated, this is only an example, and the number of transistors
may be more or less than three, based on the examples. The
plurality of transistors MH1, MH2 and MH3 may receive the detection
voltage Vd through gate resistors RG11, RG12 and RG13 connected to
the respective gates of the transistors MH, MH2 and MH3.
[0073] In an example, the voltage detection circuit 100 may include
a comparator. The comparator may compare the node voltage Vnd and
the reference voltage Vref, and may output the detection voltage Vd
having a voltage level based on a result of the comparison.
[0074] In an example, the first logic circuit 200-1, as illustrated
in FIG. 4, may include a first AND gate 210-1. The first AND gate
210-1 generates the first gate voltage Vg1a by performing a logical
multiplication of the detection voltage Vd and the first control
voltage Vg1s to generate the first gate voltage Vg1a, and may
output the generated first gate voltage Vg1a to the first gate
terminal TGE1.
[0075] FIG. 5 illustrates an example radio-frequency switching
circuit, in accordance with one or more embodiments, and FIG. 6
illustrates an example radio-frequency switching circuit, in
accordance with one or more embodiments. FIG. 7 illustrates an
example radio-frequency switching circuit, in accordance with one
or more embodiments.
[0076] Referring to FIGS. 5, 6, and 7, an example radio-frequency
switching circuit, in accordance with one or more embodiments may
include a voltage generation circuit 50, a first switching circuit
SE1, second to n-th (where n is a natural number of two or more)
switching circuit SEn, first DS resistor Rds1 to n-th DS resistor
Rdsn, a voltage detection circuit 100, and a first bypass shunt
circuit 300-1.
[0077] The first switching circuit SE1 is connected between a
common capacitor Ccom connected to an antenna port P.sub.ant and a
first capacitor Cp1 connected to a first port P1, and may perform a
switching operation with a first gate voltage Vg1a supplied through
a first gate terminal TGE1.
[0078] The n-th switching circuit SEn is connected between the
common capacitor Ccom and an n-th capacitor Cpn connected to an
n-th port Pn, and may perform a switching operation with an n-th
gate voltage Vgna received through an n-th gate terminal TGEn.
[0079] The voltage generation circuit 50 may supply a drain-source
voltage Vds to a common node Ncom.
[0080] To block DC of the drain-source voltage Vds, the common
capacitor Ccom and the first capacitor Cp1, connected to both ends
of the first switching circuit SE1, may be included. Additionally,
an n-th capacitor Cpn connected to a second end of the n-th
switching circuit SEn may be included. In an example, the common
capacitor Ccom and the first capacitor Cp1 are connected to both
ends of the first switching circuit SE1, and the common capacitor
Ccom and the n-th capacitor Cpn are connected to both ends of the
n-th switching circuit SEn.
[0081] The common capacitor Ccom is connected between the antenna
port P.sub.ant and the first switching circuit SE1, and the first
capacitor Cp1 is connected between the first switching circuit SE1
and the first port P1. Additionally, the n-th capacitor Cpn is
connected between the n-th switching circuit SEn and the n-th port
Pn.
[0082] The first DS resistor Rds1 may be connected between the
common node Ncom and a second end N1 of the first switching circuit
SE1. The n-th DS resistor Rdsn may be connected between the common
node Ncom and a second end Nn of the n-th switching circuit
SEn.
[0083] Specifically, the first DS resistor Rds1 may be connected
between both ends of the first switching circuit SE1, to enable the
drain-source voltage Vds to be applied to both ends of the first
switching circuit SE1. Additionally, the n-th DS resistor Rdsn may
be connected between both ends of the n-th switching circuit SEn,
to enable the drain-source voltage Vds to be applied to both ends
of the n-th switching circuit SEn.
[0084] The voltage detection circuit 100 may receive a node voltage
Vnd from a common node Ncom, may compare the node voltage Vnd with
a reference voltage Vref, and may generate a detection voltage Vd
including damage information or operational information pertaining
to a state of the common capacitor Ccom or the first capacitor
Cp1.
[0085] Referring to FIGS. 5 and 7, the radio-frequency switching
circuit may include a first logic circuit 200-1 to an n-th logic
circuit 200-n.
[0086] The first logic circuit 200-1 may control the level of the
first gate voltage Vg1a of the first switching circuit SE1 based on
the detection voltage Vd. The n-th logic circuit 200-n may control
the level of the n-th gate voltage Vgna of the n-th switching
circuit SEn, based on the detection voltage Vd.
[0087] In an example, the first logic circuit 200-1 may include a
first AND gate 210-1. The first AND gate 210-1 generates the first
gate voltage Vg1a by performing a logical multiplication of the
detection voltage Vd and the first control voltage Vg1s, and may
output the generated first gate voltage Vg1a to the first gate
terminal TGE1.
[0088] The n-th logic circuit 200-n may include an n-th AND gate
210-n. The n-th AND gate 210-n generates the n-th gate voltage Vgna
by performing a logical multiplication of the detection voltage Vd
and the n-th control voltage Vgns, to output the generated n-th
gate voltage Vgna to the n-th gate terminal TGEn.
[0089] Referring to FIGS. 6 and 7, the radio-frequency switching
circuit may include a first bypass shunt circuit 300-1 to an n-th
bypass shunt circuit 300-n.
[0090] The first bypass shunt circuit 300-1 may be connected
between a first end Ncom or a second end N1 of the first switching
circuit SE1 and a ground, and may perform a switching operation
based on the detection voltage Vd. In an example, the first bypass
shunt circuit 300-1 may perform a switching operation with the
detection voltage Vd input through a first shunt gate terminal
TGH1. In this example, when the detection voltage Vd is a
high-level voltage, the first bypass shunt circuit 300-1 may be
turned on, and when the detection voltage Vd is a low-level
voltage, the first bypass shunt circuit 300-1 may be turned
off.
[0091] Further, the n-th bypass shunt circuit 300-n is connected
between a first end Ncom or a second end Nn of the n-th switching
circuit SEn and the ground, and may perform a switching operation
based on the detection voltage Vd. In an example, the n-th bypass
shunt circuit 300-n may perform a switching operation according to
the detection voltage Vd input through the n-th shunt gate terminal
TGHn. In this example, when the detection voltage Vd is a
high-level voltage, the n-th bypass shunt circuit 300-n may be
turned on, and when the detection voltage Vd is a low-level
voltage, the n-th bypass shunt circuit 300-n may be turned off.
[0092] The first bypass shunt circuit 300-1 may include a plurality
of transistors MH1, MH2 and MH3 stacked with each other in series,
and performing a switching operation based on the detection voltage
Vd. The plurality of transistors MH1, MH2 and MH3 may receive the
detection voltage Vd through gate resistors RG11, RG12 and RG13
connected to gates, respectively.
[0093] Further, the n-th bypass shunt circuit 300-n may also
include a plurality of transistors, similarly to the first bypass
shunt circuit 300-1.
[0094] FIG. 8 illustrates an example voltage detection circuit, in
accordance with one or more embodiments.
[0095] Referring to FIG. 8, the voltage detection circuit 100 may
further include a comparator 110. When the node voltage Vnd is
higher than the reference voltage Vref, the comparator 110 may
output the detection voltage Vd having a first level, and when the
node voltage Vnd is lower than the reference voltage Vref, the
comparator 110 may output the detection voltage Vd having a second
level.
[0096] In an example, when one or more of the first to n-th
capacitors CP1 to CPn connected to respective ports are destroyed
or damaged, damage to one or more of the first to n-th capacitors
CP1 to CPn may be detected by detecting the DC voltage state of the
signal node, using the principle that the drain-source voltage Vds
is changed due to an externally used device and a connected
configuration circuit.
[0097] Accordingly, the operation of the series switch may be
controlled using the detection voltage Vd.
[0098] FIG. 9 is a graph of input power-insertion loss depending on
whether DC drain-source voltage is supplied or not.
[0099] In FIG. 9, G1 is a graph illustrating input power-insertion
loss for an example in which a DC drain-source voltage Vds is not
supplied, and G2 is a graph of input power-insertion loss for an
example in which a DC drain-source voltage Vds is supplied.
[0100] Referring to G1 and G2 of FIGS. 9, G1 and G2 exhibit
different insertion loss characteristics at 15 [dBm] or more
depending on the presence or absence of supply of the DC
drain-source voltage Vds.
[0101] On the other hand, when a DC blocking capacitor such as the
common capacitor Ccom, the first to n-th capacitors CP1 to CPn, or
the like, is damaged and thus the signal line to which the common
connection node Ncom is connected is grounded, the insertion loss
(dB) in G1 is lower than G2 at 25 [dBm] or more as illustrated in
FIG. 9. Therefore, based on this point, a determination whether the
DC blocking capacitor is damaged may be ascertained by observing
the node voltage Vnd at the common node Ncom.
[0102] As set forth above, according to respective examples, by
adding a detection circuit detecting the direct current (DC)
voltage of a signal node, the normal operating state of a DC
blocking capacitor may be simply checked at relatively low
costs.
[0103] Additionally, the gate voltage of the corresponding series
switch may be adjusted depending on the detection result of the DC
voltage of the signal node, thereby controlling the operation of
the corresponding series switch.
[0104] Further, the detection voltage based on the detection result
of the DC voltage of the signal node may be supplied to a gate
terminal of the corresponding bypass shunt circuit connected
between the corresponding series switch and the ground, to control
the operation of the bypass shunt circuit.
[0105] While this disclosure includes specific examples, it will be
apparent after an understanding of the disclosure of this
application that various changes in form and details may be made in
these examples without departing from the spirit and scope of the
claims and their equivalents. The examples described herein are to
be considered in a descriptive sense only, and not for purposes of
limitation. Descriptions of features or aspects in each example are
to be considered as being applicable to similar features or aspects
in other examples. Suitable results may be achieved if the
described techniques are performed to have a different order,
and/or if components in a described system, architecture, device,
or circuit are combined in a different manner, and/or replaced or
supplemented by other components or their equivalents. Therefore,
the scope of the disclosure is defined not by the detailed
description, but by the claims and their equivalents, and all
variations within the scope of the claims and their equivalents are
to be construed as being included in the disclosure.
* * * * *