U.S. patent application number 14/810100 was filed with the patent office on 2017-02-02 for alternating current to direct current converter system.
The applicant listed for this patent is HON HAI PRECISION INDUSTRY CO., LTD.. Invention is credited to CHE-HSUN CHEN, YU-CHING CHIEN, CHUANG-WEI TSENG.
Application Number | 20170033709 14/810100 |
Document ID | / |
Family ID | 57883745 |
Filed Date | 2017-02-02 |
United States Patent
Application |
20170033709 |
Kind Code |
A1 |
CHEN; CHE-HSUN ; et
al. |
February 2, 2017 |
ALTERNATING CURRENT TO DIRECT CURRENT CONVERTER SYSTEM
Abstract
An alternating current to direct current converter system
includes an alternating current power supply, an external
electronic load, a first MOS transistor, a first control module, a
first switch and a second control module. The alternating current
power supply includes a first output end and a second output end.
The first control module controls the first MOS transistor to
active when the first output end has a positive voltage and control
the first MOS transistor to turn off when the second output end has
a positive voltage. The first switch connects to a first end of the
external electronic load and the second output end. The second
control module connects to the first switch. The second control
module controls the first switch to active when the second output
end has a positive voltage and controls the switch to turn off when
the first output end has a positive voltage.
Inventors: |
CHEN; CHE-HSUN; (New Taipei,
TW) ; TSENG; CHUANG-WEI; (New Taipei, TW) ;
CHIEN; YU-CHING; (New Taipei, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
HON HAI PRECISION INDUSTRY CO., LTD. |
New Taipei |
|
TW |
|
|
Family ID: |
57883745 |
Appl. No.: |
14/810100 |
Filed: |
July 27, 2015 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02M 7/217 20130101 |
International
Class: |
H02M 7/537 20060101
H02M007/537 |
Claims
1. An alternating current to direct current converter system
comprising: an alternating current power supply system comprising a
first output end and a second output end; an external electronic
load having a first end and a second end; a first MOS transistor
having a drain electrode, a source electrode and a gate electrode,
the drain electrode of the first MOS transistor connected to the
first output end of the alternating current power supply, and the
source electrode of the first MOS transistor connected to the first
end of the external electronic load; a first control module
connected to the gate electrode of the first MOS transistor and the
source electrode of the first MOS transistor, the first control
module configured to control the drain electrode of the first MOS
transistor to connect the source electrode of the first MOS
transistor in event the first output end of the alternating current
power supply has a positive voltage with respect to the alternating
current power supply in a first half cycle, and control the drain
electrode of the first MOS transistor to disconnect the source
electrode of the first MOS transistor in event the second output
end of the alternating current power supply has a positive voltage
with respect to the alternating current power supply in a second
half cycle; a first switch connected to the first end of the
external electronic load and the second output end of the
alternating current power supply; and a second control module
connected to the first switch, the second control module configured
to control the first switch to activate in event the second output
end of the alternating current power supply has a positive voltage
with respect to the alternating current power supply in the second
half cycle and control the switch to turn off in event the first
output end of the alternating current power supply has a positive
voltage with respect to the alternating current power supply in the
first half cycle.
2. The alternating current to direct current converter system as
claimed in claim 1, wherein the first control module further
comprises a first charge and discharge module, when the second
output end of the alternating current power supply outputs positive
voltage, the first charge and discharge module is charged by the
current from the first switch, when the first output end of the
alternating current power supply outputs positive voltage, the
first charge and discharge module discharges to make the voltage of
the gate electrode of the first MOS transistor higher than the
voltage of the source electrode of the first MOS transistor to
connect the drain electrode of the first MOS transistor to the
source electrode of the first MOS transistor.
3. The alternating current to direct current converter system as
claimed in claim 2, wherein the first control module further
comprises a second charge and discharge module, the second charge
and discharge module connects to the first charge and discharge
module and the alternating current power supply, when the first
output end of the alternating current power supply outputs positive
voltage, the second charge and discharge module is charged by the
current from the first output end of the alternating current power
supply, when the second output end of the alternating current power
supply outputs positive voltage, the second charge and discharge
module discharges to connect the first charge and discharge module
to make the voltage of the gate electrode of the first MOS
transistor equal to the voltage of the source electrode of the
first MOS transistor to disconnect the drain electrode of the first
MOS transistor to the source electrode of the first MOS
transistor.
4. The alternating current to direct current converter system as
claimed in claim 3, wherein the first charge and discharge module
comprises a first capacitance, the first capacitance is charged by
the current from the first switch when the second output end of the
alternating current power supply outputs positive voltage.
5. The alternating current to direct current converter system as
claimed in claim 4, wherein the first charge and discharge module
further comprises a first resistance and a second resistance, a
first end of the first capacitance connects to the drain electrode
of the second MOS transistor and a first end of the first
resistance, a first end of the second resistance connects to the
second end of the first resistance and the gate electrode of the
first MOS transistor, a second end of the second resistance
connects to the second end of the first capacitance and the source
electrode of the first MOS transistor.
6. The alternating current to direct current converter system as
claimed in claim 5, wherein the first switch is a second MOS
transistor.
7. The alternating current to direct current converter system as
claimed in claim 6, wherein a drain electrode of the second MOS
transistor connects to the second output end of the alternating
current power supply, a source electrode of the second MOS
transistor connects to the first end of the external electronic
load.
8. The alternating current to direct current converter system as
claimed in claim 7, wherein the second control module connects to a
gate electrode of the second MOS transistor and the source
electrode of the second MOS transistor, the second control module
controls the drain electrode of the second MOS transistor to
connect the source electrode of the second MOS transistor when the
second output end of the alternating current power supply outputs
positive voltage and controls the drain electrode of the second MOS
transistor to disconnect the source electrode of the second MOS
transistor when the first output end of the alternating current
power supply outputs positive voltage.
9. The alternating current to direct current converter system as
claimed in claim 8, wherein a third resistance connects between the
first end of the first capacitance and the drain electrode of the
second MOS transistor.
10. The alternating current to direct current converter system as
claimed in claim 9, wherein the second charge and discharge module
comprises a second capacitance, a fourth resistance and a third MOS
transistor, the first end of the second capacitance connects to a
first end of the fourth resistance, the first output end of the
alternating current power supply of the alternating current power
supply and the gate electrode of the third MOS transistor, the
drain electrode of the third MOS transistor connects to the first
end of the second resistance, the source electrode of the third MOS
transistor connects to the second end of the second resistance, the
second end of the second capacitance connects to the second output
end of the alternating current power supply, a second end of the
fourth resistance connects to second output end of the alternating
current power supply.
11. An alternating current to direct current converter system
comprising: an alternating current power supply comprising a first
output end and a second output end; an external electronic load
having a first end and a second end; a first MOS transistor having
a drain electrode, a source electrode and a gate electrode, the
drain electrode of the first MOS transistor connected to a first
output end of the alternating current power supply, the source
electrode of the first MOS transistor connected to the first end of
the external electronic load; a first control module connected to
the gate electrode of the first MOS transistor and the source
electrode of the first MOS transistor, the first control module
configured to control the drain electrode of the first MOS
transistor to connect the source electrode of the first MOS
transistor in even the first output end of the alternating current
power supply has a positive voltage with respect to the alternating
current power supply in a first half cycle and control the drain
electrode of the first MOS transistor to disconnect the source
electrode of the first MOS transistor in event the second output
end of the alternating current power supply has a positive voltage
with respect to the alternating current power supply in a second
half cycle; a second MOS transistor, a drain electrode of the
second MOS transistor connects to the second output end of the
alternating current power supply, a source electrode of the second
MOS transistor connects to the first end of the external electronic
load; and a second control module connected to a gate electrode of
the second MOS transistor and the source electrode of the second
MOS transistor, the second control module configured to control the
drain electrode of the second MOS transistor to connect the source
electrode of the second MOS transistor in event the second output
end of the alternating current power supply has a positive voltage
with respect to the alternating current power supply in the second
half cycle and control the drain electrode of the second MOS
transistor to disconnect the source electrode of the second MOS
transistor in event the first output end of the alternating current
power supply has a positive voltage with respect to the alternating
current power supply in the first half cycle.
12. The alternating current to direct current converter system as
claimed in claim 11, wherein a first diode connects between the
first MOS transistor and the external electronic load.
13. The alternating current to direct current converter system as
claimed in claim 11, wherein a second diode connects between the
second MOS transistor and the external electronic load.
14. The alternating current to direct current converter system as
claimed in claim 11, wherein the first control module further
comprises a first charge and discharge module, when the second
output end of the alternating current power supply of the
alternating current power supply outputs positive voltage, the
first charge and discharge module is charged by the current from
the second MOS transistor, when the first output end of the
alternating current power supply of the alternating current power
supply outputs positive voltage, the first charge and discharge
module discharges to make the voltage of the gate electrode of the
first MOS transistor higher than the voltage of the source
electrode of the first MOS transistor to connect the drain
electrode of the first MOS transistor to the source electrode of
the first MOS transistor.
15. The alternating current to direct current converter system as
claimed in claim 14, wherein the first control module further
comprises a second charge and discharge module, the second charge
and discharge module connects to the first charge and discharge
module and the alternating current power supply, when the first
output end of the alternating current power supply outputs positive
voltage, the second charge and discharge module is charged by the
current from the first output end of the alternating current power
supply, when the second output end of the alternating current power
supply outputs positive voltage, the second charge and discharge
module discharges to connect the first charge and discharge module
to make the voltage of the gate electrode of the first MOS
transistor equal to the voltage of the source electrode of the
first MOS transistor to disconnect the drain electrode of the first
MOS transistor to the source electrode of the first MOS
transistor.
16. The alternating current to direct current converter system as
claimed in claim 15, wherein the first charge and discharge module
comprises a first capacitance, the first capacitance is charged by
the current from the second MOS transistor when the second output
end of the alternating current power supply outputs positive
voltage.
17. The alternating current to direct current converter system as
claimed in claim 16, wherein the first charge and discharge module
further comprises a first resistance and a second resistance, a
first end of the first capacitance connects to the drain electrode
of the second MOS transistor and a first end of the first
resistance, a first end of the second resistance connects to the
second end of the first resistance and the gate electrode of the
first MOS transistor, a second end of the second resistance
connects to the second end of the first capacitance and the source
electrode of the first MOS transistor.
18. The alternating current to direct current converter system as
claimed in claim 17, wherein a third resistance connects between
the first end of the first capacitance and the drain electrode of
the second MOS transistor.
19. The alternating current to direct current converter system as
claimed in claim 18, wherein the second charge and discharge module
comprises a second capacitance, a fourth resistance and a third MOS
transistor, the first end of the second capacitance connects to a
first end of the fourth resistance, the first output end of the
alternating current power supply of the alternating current power
supply and the gate electrode of the third MOS transistor, the
drain electrode of the third MOS transistor connects to the first
end of the second resistance, the source electrode of the third MOS
transistor connects to the second end of the second resistance, the
second end of the second capacitance connects to the second output
end of the alternating current power supply, a second end of the
fourth resistance connects to second output end of the alternating
current power supply.
20. The alternating current to direct current converter system as
claimed in claim 18, wherein a third diode connects between the
third resistance and the drain electrode of the second MOS
transistor.
Description
FIELD
[0001] The subject matter herein generally relates to an
alternating current to direct current converter system.
BACKGROUND
[0002] Alternating current to direct current converter systems
generally includes a plurality of diodes and microcontrollers to
control direction of current. When the current flows the diode, a
part of electronic energy is lost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] Implementations of the present technology will now be
described, by way of example only, with reference to the attached
FIGURE.
[0004] The FIGURE is a circuit diagram of an alternating current to
direct current converter system according to an exemplary
embodiment.
DETAILED DESCRIPTION
[0005] It will be appreciated that for simplicity and clarity of
illustration, where appropriate, reference numerals have been
repeated among the different FIGURES to indicate corresponding or
analogous elements. In addition, numerous specific details are set
forth in order to provide a thorough understanding of the
embodiments described herein. However, it will be understood by
those of ordinary skill in the art that the embodiments described
herein can be practiced without these specific details. In other
instances, methods, procedures, and components have not been
described in detail so as not to obscure the related relevant
feature being described. The drawings are not necessarily to scale
and the proportions of certain parts may be exaggerated to better
illustrate details and features. The description is not to be
considered as limiting the scope of the embodiments described
herein.
[0006] A definition that apply throughout this disclosure will now
be presented.
[0007] The term "comprising" means "including, but not necessarily
limited to"; it specifically indicates open-ended inclusion or
membership in a so-described combination, group, series, and the
like.
[0008] The FIGURE illustrates an alternating current to direct
current converter system 100 including an alternating current power
supply V.sub.AC, a first MOS transistor M1, a first control module
20, a second MOS transistor M2, a second control module 40, a first
diode D1, a second diode D2 and an external electronic load R0. The
alternating current power supply V.sub.AC configured to provide an
alternating current. The alternating current to direct current
converter system 100 is configured to convert the alternating
current to a direct current to load on the external electronic load
R0.
[0009] The first MOS transistor M1 includes a gate electrode G1, a
drain electrode D1 and a source electrode S1. The gate electrode G1
of the first MOS transistor M1 connects to the first control module
20. The drain electrode D1 of the first MOS transistor M1 connects
to a first output end of the alternating current power supply
V.sub.AC. The source electrode S1 of the first MOS transistor M1
connects to a first end E1 of the external electronic load R0. A
second end E2 of the external electronic load R0 connects to the
second output end of the alternating current power supply V.sub.AC
through the first diode D1. The first control module 20 is
configured to connect the drain electrode D1 of the first MOS
transistor M1 to the source electrode S1 of the first MOS
transistor M1 when the first output end of the alternating current
power supply V.sub.AC outputs positive voltage and disconnect the
drain electrode D1 of the first MOS transistor M1 to the source
electrode S1 of the first MOS transistor M1 when the second output
end of the alternating current power supply V.sub.AC outputs
positive voltage.
[0010] The gate electrode G2 of the second MOS transistor M2
connects to the second control module 40. The drain electrode D2 of
the second MOS transistor M2 connects to a second output end of the
alternating current power supply V.sub.AC. The source electrode S2
of the second MOS transistor M2 connects to the first end E1 of the
external electronic load R0. The second end E2 of the external
electronic load R0 further connects to the first output end of the
alternating current power supply V.sub.AC through the second diode
D2. The second control module 40 is configured to connect the drain
electrode D2 of the second MOS transistor M2 to the source
electrode S2 of the second transistor M2 when the second output end
of the alternating current power supply V.sub.AC outputs positive
voltage and disconnect the drain electrode D2 of the second MOS
transistor M2 to the source electrode S2 of the second MOS
transistor M2 when the first output end of the alternating current
power supply V.sub.AC outputs positive voltage.
[0011] When the alternating current power supply V.sub.AC in a
first half cycle, the first output end of the alternating current
power supply V.sub.AC outputs positive voltage, the drain electrode
D1 of the first MOS transistor M1 connects to the source electrode
S1 of the first MOS transistor M1 and the drain electrode D2 of the
second MOS transistor M2 disconnects to the source electrode S2 of
the second transistor M2. Thus, the current flows from first output
end of the alternating current power supply V.sub.AC to second
output end of the alternating current power supply V.sub.AC through
the first MOS transistor M1, the first end E1 of the external
electronic load R0, the second end E2 of the external electronic
load R0 and the first diode D1 in turn. Thus, when the first output
end of the alternating current power supply V.sub.AC outputs
positive voltage, the current can flows from the first end E1 of
the external electronic load R0 to the second end E2 of the
external electronic load R0. When the alternating current power
supply V.sub.AC in a second half cycle, the second output end of
the alternating current power supply V.sub.AC outputs positive
voltage, the drain electrode D2 of the second MOS transistor M2
connects to the source electrode S2 of the second MOS transistor M2
and the drain electrode D1 of the first MOS transistor M1
disconnects to the source electrode S1 of the first transistor M1.
Thus, the current flows from second output end of the alternating
current power supply V.sub.AC to first output end of the
alternating current power supply V.sub.AC through the second MOS
transistor M2, the first end E1 of the external electronic load R0,
the second end E2 of the external electronic load R0 and the second
diode D2 in turn. Thus, when the second output end of the
alternating current power supply V.sub.AC outputs positive voltage,
the current also can flows from the first end E1 of the external
electronic load R0 to the second end E2 of the external electronic
load R0.
[0012] The first control module 20 includes a first charge and
discharge module 22 and a second charge and discharge module 24.
The first charge and discharge module 22 connects the first MOS
transistor M1 and the second MOS transistor M2. When the second
output end of the alternating current power supply V.sub.AC outputs
positive voltage, the first charge and discharge module 22 is
configured to be charged by the current from the second MOS
transistor M2. When the first output end of the alternating current
power supply V.sub.AC outputs positive voltage, the first charge
and discharge module 22 is configured to discharge to make the
voltage of the gate electrode G1 of the first MOS transistor M1
higher than the voltage of the source electrode S1 of the first MOS
transistor M1 to connect the drain electrode D1 of the first MOS
transistor M1 to the source electrode S1 of the first MOS
transistor M1.
[0013] The second charge and discharge module 24 connects to the
first charge and discharge module 22 and the alternating current
power supply V.sub.AC. When the first output end of the alternating
current power supply V.sub.AC outputs positive voltage, the second
charge and discharge module 24 is configured to be charged by the
current from the first output end of the alternating current power
supply V.sub.AC. When the second output end of the alternating
current power supply V.sub.AC outputs positive voltage, the second
charge and discharge module 24 is configured to discharge to
connect the first charge and discharge module 22 to make the
voltage of the gate electrode G1 of the first MOS transistor M1
equal to the voltage of the source electrode S1 of the first MOS
transistor M1 to disconnect the drain electrode D1 of the first MOS
transistor M1 to the source electrode S1 of the first MOS
transistor M1.
[0014] The first charge and discharge module 22 includes a first
capacitance Cbp, a first resistance Rp1 and a second resistance
Rp2. A first end of the first capacitance Cbp connects to the drain
electrode D2 of the second MOS transistor M2 and a first end of the
first resistance Rp1. A first end of the second resistance Rp2
connects to the second end of the first resistance Rp1 and the gate
electrode G1 of the first MOS transistor M1. A second end of the
second resistance Rp2 connects to the second end of the first
capacitance Cbp and the source electrode S1 of the first MOS
transistor M1. A third resistance Rbp and a third diode Dbp connect
between the first end of the first capacitance Cbp and the drain
electrode D2 of the second MOS transistor M2.
[0015] The second charge and discharge module 24 includes a second
capacitance Csp, a fourth resistance Rsp and a third MOS transistor
Msp. The first end of the second capacitance Csp connects to a
first end of the fourth resistance Rsp, the first output end of the
alternating current power supply V.sub.AC and the gate electrode G3
of the third MOS transistor Msp. The drain electrode D3 of the
third MOS transistor Msp connects to the first end of the second
resistance Rp2. The source electrode S3 of the third MOS transistor
Msp connects to the second end of the second resistance Rp2. The
second end of the second capacitance Csp connects to the second
output end of the alternating current power supply V.sub.AC. A
second end of the fourth resistance Rsp connects to second output
end of the alternating current power supply V.sub.AC. A fourth
diode Dsp connects between the first output end of the alternating
current power supply V.sub.AC and the first end of the second
capacitance Csp.
[0016] The second control module 40 includes a third charge and
discharge module 42 and a fourth charge and discharge module 44.
The third charge and discharge module 42 connects the first MOS
transistor M1 and the second MOS transistor M2. When the first
output end of the alternating current power supply V.sub.AC outputs
positive voltage, the third charge and discharge module 42 is
configured to be charged by the current from the first MOS
transistor M1. When the second output end of the alternating
current power supply V.sub.AC outputs positive voltage, the third
charge and discharge module 42 is configured to discharge to the
second MOS transistor M2 to make the voltage of the gate electrode
G2 of the second MOS transistor M2 higher than the voltage of the
source electrode S2 of the second MOS transistor M2 to connect the
drain electrode D2 of the second MOS transistor M2 to the source
electrode S2 of the second MOS transistor M2.
[0017] The fourth charge and discharge module 44 connects to the
third charge and discharge module 42 and the alternating current
power supply V.sub.AC. When the second output end of the
alternating current power supply V.sub.AC outputs positive voltage,
the fourth charge and discharge module 44 is configured to be
charged by the current from the second output end of the
alternating current power supply V.sub.AC. When the first output
end of the alternating current power supply V.sub.AC outputs
positive voltage, the fourth charge and discharge module 44 is
configured to discharge to make the voltage of the gate electrode
G2 of the second MOS transistor M2 equal to the voltage of the
source electrode S2 of the second MOS transistor M2 to disconnect
the drain electrode D2 of the second MOS transistor M2 to the
source electrode S2 of the second MOS transistor M2.
[0018] The third charge and discharge module 42 includes a third
capacitance Cbn, a fifth resistance Rn1 and a sixth resistance Rn2.
A first end of the third capacitance Cbn connects to the drain
electrode D1 of the first MOS transistor M1 and a first end of the
fifth resistance Rn1. A first end of the sixth resistance Rn2
connects to the second end of the fifth resistance Rn1 and the gate
electrode G2 of the second MOS transistor M2. A second end of the
sixth resistance Rn2 connects to the second end of the third
capacitance Cbn and the source electrode S2 of the second MOS
transistor M2. A seventh resistance Rbn and a fifth diode Dbp
connect between the first end of the third capacitance Cbn and the
drain electrode D1 of the first MOS transistor M1.
[0019] The fourth charge and discharge module 44 includes a fourth
capacitance Csn, an eighth resistance Rsn and a fourth MOS
transistor Msn. The first end of the fourth capacitance Csn
connects to a first end of the eighth resistance Rsn, the second
output end of the alternating current power supply V.sub.AC and the
gate electrode G4 of the fourth MOS transistor Msn. The drain
electrode D4 of the fourth MOS transistor Msn connects to the first
end of the sixth resistance Rn2. The source electrode S4 of the
fourth MOS transistor Msn connects to the second end of the sixth
resistance Rn2. The second end of the fourth capacitance Csn
connects to the first output end of the alternating current power
supply V.sub.AC. A second end of the eighth resistance Rsn connects
to second output end of the alternating current power supply
V.sub.AC. A sixth diode Dsn connects between the second output end
of the alternating current power supply V.sub.AC and the first end
of the fourth capacitance Csn.
[0020] When the second output end of the alternating current power
supply V.sub.AC outputs positive voltage, the current flows through
the second MOS transistor M2 to charge the first capacitance Cbp.
When the first output end of the alternating current power supply
V.sub.AC outputs positive voltage, the first capacitance Cbp
discharges to form a current through the first resistance Rp1 and
the second resistance Rp2. The first end of the second resistance
Rp2 and second end of the second resistance Rp2 respectively
connect the gate electrode G1 of the first MOS transistor M1 and
the source electrode S1 of the first MOS transistor M1. Thus, the
voltage of the gate electrode G1 of the first MOS transistor M1 is
higher than the voltage of the source electrode S1 of the first MOS
transistor M1 to make the source electrode S1 of the first MOS
transistor M1 connect to the drain electrode D1 of the first MOS
transistor M1. Therefore, when first output end of the alternating
current power supply V.sub.AC outputs positive voltage, the current
from the first output end of the alternating current power supply
V.sub.AC can flow the first MOS transistor M1 and the third
capacitance Cbn is charged by the current from the first MOS
transistor M1. When the first output end of the alternating current
power supply V.sub.AC outputs positive voltage, the second
capacitance Csp is also charged by the current from the first
output end of the alternating current power supply V.sub.AC.
[0021] When the second output end of the alternating current power
supply V.sub.AC outputs positive voltage, the second capacitance
Csp discharges to form a current through the fourth resistance Rsp.
The first end of the fourth resistance Rsp and second end of the
fourth resistance Rsp respectively connect the gate electrode G3 of
the third MOS transistor Msp and the source electrode S3 of the
third MOS transistor Msp. Thus, the voltage of the gate electrode
G3 of the third MOS transistor Msp is higher than the voltage of
the source electrode S3 of the third MOS transistor Msp to make the
source electrode S3 of the third MOS transistor Msp connect to the
drain electrode D3 of the third MOS transistor M3. Because the
drain electrode D3 of the third MOS transistor Msp connects to the
first end of the second resistance Rp2 and the source electrode S3
of the third MOS transistor Msp connects to the second end of the
second resistance Rp2, the voltage between two ends of the second
resistance Rp2 is zero when the source electrode S3 of the third
MOS transistor Msp connect to the drain electrode D3 of the third
MOS transistor M3. The two ends of the second resistance Rp2
connect to the gate electrode G1 of the first MOS transistor M1 and
the source electrode S1 of the first MOS transistor M1. Therefore,
when the second output end of the alternating current power supply
outputs positive voltage, the voltage of the gate electrode G1 of
the first MOS transistor M1 is equal to the source electrode S1 of
the first MOS transistor M1 to disconnect the drain electrode D1 of
the first MOS transistor M1 and the source electrode S1 of the
first MOS transistor M1.
[0022] When the first output end of the alternating current power
supply V.sub.AC outputs positive voltage, the third capacitance Cbn
is charged. When the second output end of the alternating current
power supply V.sub.AC outputs positive voltage, the third
capacitance Cbn discharge to form a current through the fifth
resistance Rn1 and the sixth resistance Rn2. The first end of the
sixth resistance Rn2 and second end of the sixth resistance Rn2
respectively connect the gate electrode G2 of the second MOS
transistor M2 and the source electrode S2 of the second MOS
transistor M2. Thus, the voltage of the gate electrode G2 of the
second MOS transistor M2 is higher than the voltage of the source
electrode S2 of the second MOS transistor M2 to make the source
electrode S2 of the second MOS transistor M2 connect to the drain
electrode D2 of the second MOS transistor M2. Therefore, when
second output end of the alternating current power supply V.sub.AC
outputs positive voltage, the current from the second output end of
the alternating current power supply V.sub.AC can flow the second
MOS transistor M2 and the first capacitance Cbp is charged by the
current from the second MOS transistor M2. When the second output
end of the alternating current power supply V.sub.AC outputs
positive voltage, the fourth capacitance Csn is also charged by the
current from the second output end of the alternating current power
supply V.sub.AC.
[0023] When the first output end of the alternating current power
supply V.sub.AC outputs positive voltage, the fourth capacitance
Csn discharges to form a current through the eighth resistance Rsn.
The first end of the eighth resistance Rsn and second end of the
eighth resistance Rsn respectively connect the gate electrode G4 of
the fourth MOS transistor Msn and the source electrode S4 of the
fourth MOS transistor Msn. Thus, the voltage of the gate electrode
G4 of the fourth MOS transistor Msn is higher than the voltage of
the source electrode S4 of the fourth MOS transistor Msn to make
the source electrode S4 of the fourth MOS transistor Msn connect to
the drain electrode D4 of the fourth MOS transistor Msn. Because
the drain electrode D4 of the fourth MOS transistor Msn connects to
the first end of the sixth resistance Rn2 and the source electrode
S4 of the fourth MOS transistor Msn connects to the second end of
the sixth resistance Rn2, the voltage between two ends of the sixth
resistance Rn2 is zero when the source electrode S4 of the fourth
MOS transistor Msn connect to the drain electrode D4 of the fourth
MOS transistor Msn. The two ends of the sixth resistance Rn2
connect to the gate electrode G2 of the second MOS transistor M2
and the source electrode S2 of the second MOS transistor M2.
Therefore, when the first output end of the alternating current
power supply V.sub.AC outputs positive voltage, the voltage of the
gate electrode G2 of the second MOS transistor M2 is equal to the
source electrode S2 of the second MOS transistor M2 to disconnect
the drain electrode D2 of the second MOS transistor M2 and the
source electrode S2 of the second MOS transistor M2.
[0024] The embodiments shown and described above are only examples.
Even though numerous characteristics and advantages of the present
technology have been set forth in the foregoing description,
together with details of the structure and function of the present
disclosure, the disclosure is illustrative only, and changes may be
made in the details, including in matters of shape, size, and
arrangement of the parts within the principles of the present
disclosure, up to and including the full extent established by the
broad general meaning of the terms used in the claims.
* * * * *