U.S. patent application number 15/169715 was filed with the patent office on 2017-09-14 for regulator.
The applicant listed for this patent is Realtek Semiconductor Corporation. Invention is credited to Chih-Chien CHANG, Shih-Wei WANG, Cheng-Cheng YEN.
Application Number | 20170262006 15/169715 |
Document ID | / |
Family ID | 58766284 |
Filed Date | 2017-09-14 |
United States Patent
Application |
20170262006 |
Kind Code |
A1 |
WANG; Shih-Wei ; et
al. |
September 14, 2017 |
REGULATOR
Abstract
A regulator includes a driving circuit, an amplifying circuit
and an overvoltage protection circuit. The driving circuit is
configured to receive an input voltage and provide an output
voltage through an output terminal. The amplifying circuit is
configured to control the driving circuit according to the output
voltage. The overvoltage protection circuit is configured to
conduct a first current from the output terminal of the
overprotection circuit to a ground terminal. When the overvoltage
protection circuit detects that a voltage level of a node coupled
to the driving circuit is increased, the overvoltage protection
circuit conducts a second current from the output terminal of the
overprotection circuit to the ground terminal to lower the output
voltage, in which the second current is larger than the first
current.
Inventors: |
WANG; Shih-Wei; (Hualien
County, TW) ; YEN; Cheng-Cheng; (Hsinchu City,
TW) ; CHANG; Chih-Chien; (Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Realtek Semiconductor Corporation |
Hsinchu |
|
TW |
|
|
Family ID: |
58766284 |
Appl. No.: |
15/169715 |
Filed: |
May 31, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G05F 1/468 20130101;
H02H 7/10 20130101; G05F 1/575 20130101; G05F 1/595 20130101 |
International
Class: |
G05F 1/575 20060101
G05F001/575; G05F 1/595 20060101 G05F001/595; H02H 7/10 20060101
H02H007/10; G05F 1/46 20060101 G05F001/46 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 8, 2016 |
TW |
105107069 |
Claims
1. A regulator, comprising: a driving circuit, configured to
receive an input voltage and provide an output voltage through an
output terminal; an amplifying circuit, configured to control the
driving circuit according to the output voltage; and an overvoltage
protection circuit, configured to conduct a first current from the
output terminal of the driving circuit to a ground terminal;
wherein when the overvoltage protection circuit detects that a
voltage level of a node coupled to the driving circuit is
increased, the overvoltage protection circuit conducts a second
current from the output terminal of the driving circuit to the
ground terminal to reduce the output voltage, and the second
current is larger than the first current.
2. The regulator of claim 1, wherein the overvoltage protection
circuit comprises: a switch circuit; and a first filter circuit,
configured to control the switch circuit to conduct the second
current from the output terminal of the driving circuit to the
ground terminal to reduce the output voltage when detecting that
the voltage level of the node is increased.
3. The regulator of claim 2, further comprising: a bias circuit,
configured to output a control voltage to a control terminal of the
switch circuit to control the switch circuit to conduct the first
current from the output terminal of the driving circuit to the
ground terminal according to a bias voltage, wherein the first
current is determined according to the control voltage.
4. The regulator of claim 3, wherein the bias circuit comprises: a
bias power supply, configured to provide the bias voltage; and a
second filter circuit, configured to receive the bias voltage and
output the control voltage to control the switch circuit to conduct
the first current from the output terminal of the driving circuit
to the ground terminal.
5. The regulator of claim 4, wherein the second filter circuit is a
low pass filter.
6. The regulator of claim 4, wherein the first filter circuit
comprises a capacitor, and the second filter circuit comprises a
resistor.
7. The regulator of claim 2, wherein the first filter circuit is a
high pass filter.
8. The regulator of claim 2, wherein the node is the output
terminal of the driving circuit, the first filter circuit is
further configured to increase the control voltage by a second
voltage difference according to a first voltage difference that is
increased at the output terminal of the driving circuit, and the
second current is determined according to the control voltage and
the second voltage difference.
9. The regulator of claim 2, wherein the node is one of an output
terminal of the amplifying circuit and a control terminal of the
driving circuit, the first filter circuit is configured to increase
the control voltage by a second voltage difference according to a
first voltage difference that is increased at the node, and the
second current is determined according to the control voltage and
the second voltage difference.
10. The regulator of claim 1, wherein the amplifying circuit is
configured to amplify a difference between a feedback voltage and a
reference voltage to control the driving circuit, and the feedback
voltage corresponds to the output voltage.
11. A regulator, comprising: a transistor, having a control
terminal, a first terminal and a second terminal, wherein the
second terminal is coupled to a ground terminal, the control
terminal is configured to receive a control voltage so that the
transistor conducts a first current from the first terminal to the
second terminal; a driving circuit, having an input terminal, an
output terminal and a control terminal, wherein the output terminal
is coupled to the first terminal of the transistor, the input
terminal is configured to receive an input voltage, and the output
terminal is configured to output an output voltage; an amplifying
circuit, coupled to the control terminal of the driving circuit and
configured to control the driving circuit according to the output
voltage; and a first filter circuit, having a first terminal and a
second terminal, wherein the first terminal of the first filter
circuit is coupled to the driving circuit, the second terminal of
the first filter circuit is coupled to the control terminal of the
transistor, the first filter circuit is configured to control the
transistor to conduct a second current from the first terminal to
the second terminal to reduce the output voltage when a voltage
level at the first terminal is increased, and the second current is
larger than the first current.
12. The regulator of claim 11, wherein the first filter circuit is
further configured to increase a voltage difference at the second
terminal of the first filter circuit according to the voltage
difference that is increased at the first terminal of the first
filter circuit so that the transistor conducts the second current
from the first terminal of the transistor to the second terminal of
the transistor to reduce the output voltage.
13. The regulator of claim 11, further comprising: a bias circuit,
coupled to the control terminal of the transistor and configured to
output the control voltage to the control terminal of the
transistor according to a bias voltage so that the transistor
conducts the first current from the first terminal of the
transistor to the second terminal of the transistor, wherein the
first current is determined according to the control voltage.
14. The regulator of claim 13, wherein the bias circuit further
comprises: a bias power supply, configured to provide the bias
voltage; and a second filter circuit, coupled to the bias power
supply and the control terminal of the transistor and configured to
receive the bias voltage and output the control voltage to the
control terminal of the transistor so that the transistor conducts
the first current from the first terminal of the transistor to the
second terminal of the transistor.
15. The regulator of claim 14, wherein the second filter circuit is
a low pass filter.
16. The regulator of claim 14, wherein the first filter circuit
comprises a capacitor, and the second filter circuit comprises a
resistor.
17. The regulator of claim 11, wherein the first filter circuit is
a high pass filter.
18. The regulator of claim 11, wherein the first terminal of the
first filter circuit is coupled to the output terminal of the
driving circuit, the first filter circuit is further configured to
increase a voltage level of the second terminal of the first filter
circuit by a second voltage difference according to a first voltage
difference that is increased at the first terminal of the first
filter circuit, and the second current is determined according to
the control voltage and the second voltage difference.
19. The regulator of claim 11, wherein the first terminal of the
first filter circuit is coupled to an output terminal of the
amplifying circuit or the control terminal of the driving circuit,
the first filter circuit is further configured to increase a
voltage level of the second terminal of the first filter circuit by
a second voltage difference according to a first voltage difference
that is increased at the first terminal of the first filter
circuit, and the second current is determined according to the
control voltage and the second voltage difference.
20. The regulator of claim 11, wherein the amplifying circuit is
configured to amplify a difference between a feedback voltage and a
reference voltage to control the driving circuit, and the feedback
voltage corresponds to the output voltage.
Description
RELATED APPLICATIONS
[0001] This application claims priority to Taiwan Application
Serial Number 105107069, filed Mar. 8, 2016, which is herein
incorporated by reference.
BACKGROUND
[0002] Technical Field
[0003] The present disclosure relates to a regulator. More
particularly, the present disclosure relates to a regulator for
preventing output overvoltage.
[0004] Description of Related Art
[0005] A low dropout regulator (LDO) is widely applied in
electronic power supplies, including use in automobile electronics,
mobile phones, notebooks. and personal digital assistants (PDA),
etc. In particular, the requirements of low power consumption, high
performance and high reliability in automobile electronics make
design of a LDO circuit more difficult. When power supply output of
the LDO circuit switches from a mode to another mode, the load
requirement of the LDO changes rapidly, which may result in an
output overvoltage or an output undervoltage. Since overvoltage may
cause permanent damage to the circuit, a protection mechanism for
preventing output overvoltage is very important.
SUMMARY
[0006] An aspect of the present disclosure provides a regulator.
The regulator includes a driving circuit, an amplifying circuit and
an overvoltage protection circuit. The driving circuit is
configured to receive an input voltage and provide an output
voltage through an output terminal. The amplifying circuit is
configured to control the driving circuit according to the output
voltage. The overvoltage protection circuit is configured to
conduct a first current from the output terminal of the driving
circuit to a ground terminal. When the overvoltage protection
circuit detects that a voltage level of a node coupled to the
driving circuit is increased, the overvoltage protection circuit
conducts a second current from the output terminal of the driving
circuit to the ground terminal to reduce the output voltage. The
second current is larger than the first current.
[0007] Another aspect of the present disclosure provides a
regulator. The regulator includes a transistor, a driving circuit,
an amplifying circuit and a first filter circuit. The transistor
has a control terminal, a first terminal and a second terminal. The
second terminal is coupled to a ground terminal, and the control
terminal is configured to receive a control voltage so that the
transistor conducts a first current from the first terminal to the
second terminal. The driving circuit has an input terminal, an
output terminal and a control terminal. The output terminal is
coupled to the first terminal of the transistor, the input terminal
is configured to receive an input voltage, and the output terminal
is configured to output an output voltage. The amplifying circuit
is coupled to the control terminal of the driving circuit and
configured to control the driving circuit according to the output
voltage. The first filter circuit has a first terminal and a second
terminal. The first terminal of the first filter circuit is coupled
to the driving circuit, the second terminal of the first filter
circuit is coupled to the control terminal of the transistor, and
the first filter circuit is configured to control the transistor to
conduct a second current from the first terminal to the second
terminal to reduce the output voltage when a voltage level at the
first terminal is increased. The second current is larger than the
first current.
[0008] In conclusion, purpose of the present disclosure is to
prevent an output overvoltage phenomenon. The regulator of the
present disclosure may directly or indirectly detect a voltage
level difference that is increased on the output voltage so as to
appropriately release excess energy at the output terminal of the
driving circuit, and therefore effectively avoid damage caused by
the overvoltage phenomenon to circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The disclosure can be more fully understood by reading the
following detailed description of the embodiments, with reference
made to the accompanying drawings as follows:
[0010] FIG. 1 is a schematic diagram of a regulator according to an
embodiment of the present disclosure;
[0011] FIG. 2 is a schematic diagram of a regulator according to an
embodiment of the present disclosure;
[0012] FIG. 3 is a schematic diagram of a regulator according to an
embodiment of the present disclosure; and
[0013] FIG. 4 is a schematic diagram of a regulator according to an
embodiment of the present disclosure.
DETAILED DESCRIPTION
[0014] Reference is made in detail to the present embodiments of
the disclosure, examples of which are illustrated in the
accompanying drawings. Wherever possible, the same reference
numbers are used in the drawings and the description to refer to
the same or like parts.
[0015] In the following description and claims, the terms "coupled"
and "connected," along with their derivatives, may be used. In
particular embodiments, "connected" and "coupled" may be used to
indicate that two or more elements are in direct physical or
electrical contact with each other, or may also mean that two or
more elements may be in indirect contact with each other. The terms
"coupled" and "connected" may still be used to indicate that two or
more elements cooperate or interact with each other.
[0016] Reference is made to FIG. 1. FIG. 1 is a schematic diagram
of a regulator according to an embodiment of the present
disclosure. The regulator may be applied to automobile electronics,
a mobile phone, a notebook and a personal digital assistant (PDA),
and the present disclosure is not limited in this regard.
[0017] The regulator includes a driving circuit 110, an amplifying
circuit 120 and an overvoltage protection circuit 130. The driving
circuit 110 is coupled to the amplifying circuit 120 and the
overvoltage protection circuit 130.
[0018] The driving circuit 110 is configured to receive an input
voltage V.sub.IN through an input terminal 1101 and provides an
output voltage V.sub.OUT to a load 140 through an output terminal
1102.
[0019] The amplifying circuit 120 is coupled to a control terminal
1103 of the driving circuit 110 and configured to control the
driving circuit 110 according to the output voltage V.sub.OUT.
Specifically, the amplifying circuit 120 is configured to amplify a
difference between the feedback voltage and the reference voltage
V.sub.REF to generate a control voltage V.sub.G, in which the
control voltage V.sub.G is to control the driving circuit 110 to
provide the output voltage V.sub.OUT. The feedback voltage may be
generated by a feedback circuit 150 (e.g., a voltage dividing
circuit) that is coupled to the output voltage V.sub.OUT.
[0020] The overvoltage protection circuit 130 is configured to
conduct a first current from the output terminal 1102 of the
driving circuit 110 to the ground terminal. For example, if a
system is affected by a voltage surge, such as from a lightning
strike, a voltage level at the output terminal 1102 of the driving
circuit 110 is increased, and a voltage level of a node P is also
increased. When the overvoltage protection circuit 130 detects that
the voltage level at the node P of the driving circuit 110 is
increased, the overvoltage protection circuit 130 conducts a second
current from the output terminal 1102 of the driving circuit 110 to
the ground terminal in order to output voltage to V.sub.OUT. It
should be noted that the second current is larger than the first
current so as to effectively prevent an overvoltage phenomenon
caused by the increased output voltage V.sub.OUT. In the present
embodiment, the overvoltage protection circuit 130 directly detects
the output voltage V.sub.OUT (i.e., the voltage level of the node
P) to prevent the output voltage V.sub.OUT from having the
overvoltage phenomenon.
[0021] As a result, when the output voltage V.sub.OUT is stable
without the overvoltage phenomenon, the overvoltage protection
circuit 130 conducts a smaller first current between the output
terminal of the driving circuit 110 and the ground terminal. When
the output voltage V.sub.OUT has the overvoltage phenomenon, the
overvoltage protection circuit 130 then releases excess energy of
the output voltage V.sub.OUT through a larger second current to
keep the output voltage at V.sub.OUT stable.
[0022] In some embodiments, the overvoltage protection circuit 130
includes a filter circuit 131, a bias circuit 132 and a switch
circuit 133. The filter circuit 131 is configured to control the
switch circuit 133 to conduct the second current from the output
terminal 1102 of the driving circuit 110 to the ground terminal in
order to reduce the output voltage V.sub.OUT when the filter
circuit detects that the voltage level of the node P is increased.
The bias circuit 132 is configured to output a control voltage
V.sub.C to a control terminal 13 of the switch circuit 133 so as to
control the switch circuit 133 to conduct the first current from
the output terminal 1102 of the driving circuit 110 to the ground
terminal.
[0023] In some embodiments, the bias circuit 132 includes a bias
power supply 1321 and a filter circuit 1322. The bias power supply
1321 is configured to provide a bias voltage to the filter circuit
1322. The filter circuit 1322 is configured to receive the bias
voltage and output the control voltage V.sub.C to control the
switch circuit 133 to conduct the first current from the output
terminal 1102 of the driving circuit 110 to the ground terminal. In
some embodiments, the filter circuit 1322 may be a low pass
filter.
[0024] In some embodiments, as shown in FIG. 1, the switch circuit
133 may be implemented as a transistor M1. The transistor M1 has a
control terminal 13, a first terminal 11 and a second terminal 12.
The second terminal 12 is coupled to the ground terminal, and the
control terminal 13 is configured to receive the control voltage
V.sub.C so that the transistor M1 conducts the first current from
the first terminal 11 to the second terminal 12. The first current
is determined according to the control voltage V.sub.C. For
example, the first current may be a minimum current when the
transistor M1 is in a standby state, and the present disclosure is
not limited in this regard. In the present embodiment, the filter
circuit 131 is a high pass filter, and the filter circuit 1322 is a
low pass filter. When the output voltage V.sub.OUT has the
overvoltage phenomenon, the filter circuit 131 is configured to
increase the control voltage V.sub.C by a voltage difference
.DELTA.V.sub.2 according to a voltage difference .DELTA.V.sub.1
that is increased at the output terminal 1102 (i.e., node P) of the
driving circuit 110. In other words, when the overvoltage
phenomenon happens, a voltage level of a node Q is increased to
V.sub.C+.DELTA.V.sub.2. The transistor M1 receives
V.sub.C+.DELTA.V.sub.2 through control terminal 13 to turn on, and
generates the second current according to the voltage level
V.sub.C+.DELTA.V.sub.2 of the control terminal 13 to conduct the
output terminal 1102 of the driving circuit 110 and the ground
terminal in order to release the excess energy of the output
voltage V.sub.OUT. Therefore, the switch circuit 133 effectively
solves problem of the overvoltage phenomenon to reduce the output
voltage (i.e., node P) to V.sub.OUT and to reduce the voltage level
of the node Q to V.sub.C. Moreover, it should be noted that because
the filter circuit 1322 is a low pass filter, and the second
current generated by the switch circuit 133 causes the voltage
difference .DELTA.V.sub.1 to be rapidly decreased so that the
voltage difference .DELTA.V.sub.2 is rapidly decreased, the voltage
difference .DELTA.V.sub.2 has no negative effect on the bias
circuit 132.
[0025] In some embodiments, the voltage difference .DELTA.V.sub.1
is equal to or larger than the voltage difference
.DELTA.V.sub.2.
[0026] As a result, in a stable state, the transistor M1 is in the
standby state that has a rapid response (e.g., increasing the
current conducted between the first terminal and the second
terminal) according to change at the voltage level of the control
terminal 13 in order to release excess energy of the output voltage
V.sub.OUT and to reduce the lasting time of the overvoltage, which
avoids permanent damage to a circuit.
[0027] In the present embodiment, the amplifying circuit 120 may be
an error amplifier. The transistor M1 may be an N-type metal oxide
semiconductor field effect transistor (N-MOSFET), a P-type metal
oxide semiconductor field effect transistor (P-MOSFET), a bipolar
junction transistor (BJT), or another equivalent transistor, and
the present disclosure is not limited in this regard.
[0028] Reference is made to FIG. 2. FIG. 2 is a schematic diagram
of a regulator according to an embodiment of the present
disclosure. The regulator includes a driving circuit 110, an
amplifying circuit 120 and an overvoltage protection circuit 130 as
shown in FIG. 1. A switch circuit 133 may be a transistor M1, the
driving circuit 110 may be a transistor M2, a filter circuit 131
may be a capacitor, and a filter circuit 1322 may be a resistor.
The filter circuit 131 has a first terminal 1311 and a second
terminal 1312. The first terminal 1311 is coupled to an output
terminal 1102 (i.e., node P) of the driving circuit 110, and the
second terminal 1312 is coupled to a control terminal 13 of the
transistor M1. The bias power supply 1321 provides a bias voltage
to the filter circuit 1322, and the filter circuit 1322 outputs a
control voltage V.sub.C to the control terminal 13 of the
transistor M1 so that the transistor M1 conducts a first current
from the first terminal 11 to the second terminal 12 (i.e., the
ground terminal). In the present embodiment, the transistor M2 may
be an N-MOSFET, a P-MOSFET, a BJT or another equivalent transistor,
and the present disclosure is not limited in this regard.
[0029] When the output voltage V.sub.OUT is stable without an
overvoltage phenomenon, a voltage level of a node Q is the control
voltage V.sub.C, and the transistor M1 conducts a first current
from the first terminal 11 to the second terminal 12. When the
output voltage V.sub.OUT has the overvoltage phenomenon, the filter
circuit 131 couples a voltage difference .DELTA.V.sub.1 that is
increased at the first terminal 1311 to the second terminal 1312.
In other words, the filter circuit 131 increases a voltage level of
the second terminal 1312 by a voltage level difference
.DELTA.V.sub.2 according to the voltage difference .DELTA.V.sub.1
that is increased at the first terminal 1311, so the transistor M1
conducts a second current from the first terminal 11 to the second
terminal 12 to reduce the output voltage to V.sub.OUT. As
aforementioned, the second current is larger than the first
current.
[0030] Reference is made to FIG. 3. FIG. 3 is a schematic diagram
of a regulator according to an embodiment of the present
disclosure. The regulator in FIG. 3 includes a driving circuit 110
and an amplifying circuit 120 as shown in FIG. 1, and an
overvoltage protection circuit 330 is coupled to the driving
circuit 110 through nodes P and R. Specifically, when the
overvoltage phenomenon appears, an increased output voltage
V.sub.OUT+.DELTA.V.sub.1 causes a voltage level of the node R to be
increased to V.sub.G+.DELTA.V' through a feedback circuit 150 and
the amplifying circuit 120. In the present embodiment, the
overvoltage protection circuit 130 detects the voltage level of
control voltage V.sub.G at the node R (i.e., indirectly detecting
the output voltage V.sub.OUT) to avoid output voltage V.sub.OUT
having an overvoltage phenomenon.
[0031] The regulator shown in FIG. 3 has similar operation as
operation of the regulator shown in FIG. 1, and differences are
described herein. When the output voltage V.sub.OUT has the
overvoltage phenomenon, the filter circuit 331 is configured to
increase the control voltage V.sub.C by a voltage difference
.DELTA.V'' according to a voltage difference .DELTA.V' that is
increased at the control terminal 1103 (i.e., node R) of the
driving circuit 110. In other words, when the overvoltage
phenomenon appears, a voltage level of a node Q is increased to
V.sub.C+.DELTA.V''. The control terminal 13 of the transistor M1
receives the increased control voltage V.sub.C+.DELTA.V'' to turn
on, and generates a second current according to the control
terminal 13 voltage level V.sub.C+.DELTA.V'' to conduct an output
terminal 1102 of the driving circuit 110 and a ground terminal in
order to release excess energy of the output voltage V.sub.OUT.
Therefore, the switch circuit 133 effectively solves the
overvoltage phenomenon to reduce the voltage level of the node P to
V.sub.OUT and reduce the voltage level of the node Q to
V.sub.C.
[0032] In some embodiments, the voltage difference .DELTA.V' is
equal to or larger than the voltage difference .DELTA.V''.
[0033] Reference is made to FIG. 4. FIG. 4 is a schematic diagram
of a regulator according to an embodiment of the present
disclosure. The regulator in FIG. 4 includes a driving circuit 110,
an amplifying circuit 120 and an overvoltage protection circuit 330
as shown in FIG. 3. A switch circuit 133 may be a transistor M1,
the driving circuit 110 may be a transistor M2, a filter circuit
331 may be a capacitor, and a filter circuit 1322 may be a
resistor. The filter circuit 331 has a first terminal 3311 and a
second terminal 3312. The first terminal 3311 is coupled to a
control terminal 1103 (i.e., node R) of the driving circuit 110,
and the second terminal 1312 is coupled to a control terminal 13 of
the transistor M1. The bias power supply 1321 provides a bias
voltage to the filter circuit 1322, and the filter circuit 1322
outputs a control voltage V.sub.C to the control terminal 13 of the
transistor M1 so that the transistor M1 conducts a first current
from a first terminal 11 to a second terminal 12 (i.e., the ground
terminal).
[0034] The regulator shown in FIG. 4 has similar operation as
operation of the regulator shown in FIG. 2, and differences are
described herein. When output voltage V.sub.OUT has the overvoltage
phenomenon, the filter circuit 131 couples a voltage difference
.DELTA.V' that is increased at the first terminal 3311 (i.e., node
R) to the second terminal 3322. In other words, the filter circuit
331 increases a voltage level of the second terminal 3312 by a
voltage level difference .DELTA.V'' according to the voltage
difference .DELTA.V' that is increased at the first terminal 3311
so that the transistor M1 conducts a second current from the first
terminal 11 to the second terminal 12 in order to reduce the output
voltage to V.sub.OUT. As aforementioned, the second current is
larger than the first current.
[0035] It should be noted that the filter circuit 331 may be a
capacitor or another high pass filter circuit, filter circuit 1322
may be a resistor or another low pass filter circuit, and the
present disclosure is not limited in this regard.
[0036] In conclusion, the present disclosure provides a regulator
that prevents output voltage from overvoltage phenomenon. The
regulator of the present disclosure may directly or indirectly
detect a voltage level difference that is increased on the output
voltage so as to appropriately release excess energy at the output
terminal of the driving circuit, and therefore effectively avoid
damage caused by the overvoltage phenomenon to the circuit.
[0037] Although the present disclosure has been described in
considerable detail with reference to certain embodiments thereof,
other embodiments are possible. Therefore, the spirit and scope of
the appended claims should not be limited to the description of the
embodiments contained herein.
[0038] It will be apparent to those skilled in the art that various
modifications and variations can be made to the structure of the
present disclosure without departing from the scope or spirit of
the disclosure. In view of the foregoing, it is intended that the
present disclosure cover modifications and variations of this
disclosure provided they fall within the scope of the following
claims.
* * * * *