CN107069945A - Double loop power supply automatic switch-over circuit - Google Patents
Double loop power supply automatic switch-over circuit Download PDFInfo
- Publication number
- CN107069945A CN107069945A CN201710457106.8A CN201710457106A CN107069945A CN 107069945 A CN107069945 A CN 107069945A CN 201710457106 A CN201710457106 A CN 201710457106A CN 107069945 A CN107069945 A CN 107069945A
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- CN
- China
- Prior art keywords
- switch
- way switch
- power supply
- input
- input power
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
- H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
- H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
Abstract
The invention discloses a kind of double loop power supply automatic switch-over circuit, for switching the first input power and the second input power, including power output end, the first single-way switch, the second single-way switch and three-terminal switch circuit, three-terminal switch circuit includes first end, the second end and the 3rd end；First end, the input of the first single-way switch and the electrical connection of the first input power, second end is electrically connected with second input power, 3rd end is electrically connected with the input of second single-way switch, the output end of first single-way switch, the output end of second single-way switch and power output end electrical connection；The three-terminal switch circuit is used for when accessing second input power and disconnecting first input power so that second end and the 3rd end conducting, the three-terminal switch circuit is additionally operable to when accessing first input power so that second end and the 3rd end disconnect.Circuit of the present invention is simple and circuit small volume, so cost is relatively low.
Description
Technical field
The present invention relates to integrated circuit fields, more particularly to a kind of double loop power supply automatic switch-over circuit.
Background technology
In many control systems, it is powered using double loop power supply.USB (USB) powered products application
It is more, when the product needs to export more high-power, it is necessary to preferentially ensure the output of power from externally fed.With shown in Fig. 1
USB speaker control system exemplified by, the system includes two-way power supply, and respectively power supply A and power supply B, power supply B are USB port
Power supply, needs to automatically switch according to given power supply priority, wherein power supply A priority is higher than power supply B during the system operation
Priority.Due to the limitation of the power supply capacity of USB port, when system needs to export bigger power, it is necessary to using power supply A
Namely external AC/DC (AC-DC converter) adapters provide higher power supply capacity.Outside AC/DC or other
During plant-grid connection, system power supply needs to power from USB port to automatically switch to external AC/DC and power.
Existing power supply switch circuit typically realizes that the adjunct circuit now needed realizes complexity, is related to using relay
Component is more, causes cost of implementation higher, and the development trend that system realizes miniaturization is not met in addition yet.
The content of the invention
The technical problem to be solved in the present invention is that power supply switch circuit realization complexity, volume are big in order to overcome in the prior art
And the higher defect of cost is there is provided a kind of circuit realiration is simple, small volume and the low double loop power supply automatic switch-over circuit of cost.
The present invention is to solve above-mentioned technical problem by following technical proposals：
The invention provides a kind of double loop power supply automatic switch-over circuit, for switching the first input power and the second input electricity
Source, its feature is, including power output end, the first single-way switch, the second single-way switch and three-terminal switch circuit, three end
On-off circuit includes first end, the second end and the 3rd end；The first end, the input of first single-way switch and described
One input power is electrically connected, and second end electrically connects with second input power, the 3rd end and described second unidirectional
The input electrical connection of switch, the output end of first single-way switch, the output end of second single-way switch and described
Power output end is electrically connected；The three-terminal switch circuit is used to access second input power and disconnect first input
Second end and the 3rd end is caused to turn on during power supply, the three-terminal switch circuit is additionally operable to accessing first input
Second end and the 3rd end is caused to disconnect during power supply；Input of first single-way switch in first single-way switch
The difference that terminal voltage subtracts the output end voltage of first single-way switch is turned on when being more than the first preset value；Described second unidirectionally opens
The difference that the input terminal voltage closed in second single-way switch subtracts the output end voltage of second single-way switch is more than second
Turned on during preset value.
In this programme, power output end is used to be powered for final external load circuit.
In this programme, the three-terminal switch circuit is used to access second input power and disconnect first input
Cause second end and the 3rd end are turned on to refer to now only access the second input power during power supply, and the first input power
Do not access, now the second end and the conducting of the 3rd end, i.e. the second input power is powered by the second single-way switch for power output end.
In this programme, the three-terminal switch circuit is additionally operable to when accessing first input power so that second end
Refer to that the first input power is accessed as long as being disconnected with the 3rd end, no matter whether second source accesses, now the second end and the
Three ends disconnect, i.e., now powered by the first input power by the first single-way switch for power output end.
In this programme, the presence of the first single-way switch and the second single-way switch can prevent pouring in down a chimney between power supply.
It is preferred that first single-way switch and second single-way switch are diode.
It is preferred that first single-way switch and second single-way switch are Schottky diode.
In this programme, the first single-way switch and the second single-way switch use Schottky diode, Schottky diode
Conducting voltage is smaller, and conduction voltage drop is relatively low, and switching loss is also small, it can be ensured that the magnitude of voltage that power output end is obtained more connects
It is bordering on the supply voltage of the first input power or the second input power.
It is preferred that the double loop power supply automatic switch-over circuit also includes a resistance, one end of the resistance is grounded, the electricity
The other end of resistance is electrically connected with first input power；The three-terminal switch circuit is FET, and the first end is institute
The grid of FET is stated, second end is the source electrode of the FET, and the 3rd end is the leakage of the FET
Pole.
It is preferred that the FET is managed for PMOS (P-type mos).
In this programme, when the second input power is accessed and the first input power is not accessed, because the drop-down of resistance is made
With make it that the FET is in the conduction state, now the second input power passes through the FET and the second single-way switch
Complete the power supply to power output end.Access or the first input power and the second input power are same after the first input power
When FET cut-off when accessing, now the first input power the confession to power output end is completed by the first single-way switch
Electricity.This programme realizes the automatic switchover of two-way power supply, it is allowed to which two-way power supply is accessed simultaneously, and the first input power has more
High priority.
It is preferred that the resistance of the resistance is 1~100K Ω (kilohm).
It is preferred that the voltage of first input power is 5~20V (volt)；The voltage of second input power is 5
~20V.
The positive effect of the present invention is：The double loop power supply automatic switch-over circuit that the present invention is provided can realize control
The automatic switchover of double loop power supply in system, by the circuit allow two-way power supply simultaneously or successively access, it is ensured that different electrical power it
Between be not in pour in down a chimney, and realize the preferential power supply of power supply all the way.The present invention uses single-way switch and three-terminal switch circuit
Realize, circuit is simple and circuit small volume, so cost is relatively low.
Brief description of the drawings
Fig. 1 is the schematic diagram of the control system of USB speaker.
Fig. 2 is the double loop power supply automatic switch-over circuit operating diagram of a preferred embodiment of the present invention.
Embodiment
The present invention is further illustrated below by the mode of embodiment, but does not therefore limit the present invention to described reality
Apply among a scope.
As shown in Fig. 2 a kind of double loop power supply automatic switch-over circuit, for switching the first input power 1 and the second input electricity
Source 2, including power output end VDD, resistance R, the first single-way switch 3, the second single-way switch 4 and three-terminal switch circuit 5, three end
On-off circuit 5 includes first end 501, the second end 502 and the 3rd end 503.
In the present embodiment, resistance R one end ground connection, first end 501, the input of the first single-way switch 3, resistance R it is another
One end and the first input power 1 are electrically connected, and the second end 502 is electrically connected with the second input power 2, the 3rd end 503 and second unidirectional
The input electrical connection of switch 4, the output end of the first single-way switch 3, the output end of the second single-way switch 4 and power output end
VDD is electrically connected.Three-terminal switch circuit 5 is used to cause the second end when accessing the second input power 2 and disconnecting the first input power 1
502 and the 3rd end 503 turn on, three-terminal switch circuit 5 is additionally operable to when accessing the first input power 1 so that the second end 502 and the
Three ends 503 disconnect.First single-way switch 3 subtracts the output end of the first single-way switch 3 in the input terminal voltage of the first single-way switch 3
Difference in voltage is turned on when being more than the first preset value；Second single-way switch 4 subtracts second in the input terminal voltage of the second single-way switch 4
The difference of the output end voltage of single-way switch 4 is turned on when being more than the second preset value.
In the present embodiment, the first single-way switch 3 is realized using Schottky diode D1, and the second single-way switch 4 uses Xiao Te
Based diode D2 is realized.Three-terminal switch circuit 5 realizes that wherein first end 501 is FET Q grid using FET Q,
Second end 502 is FET Q source electrode, and the 3rd end 503 is FET Q drain electrode, and wherein FET uses PMOS.
In the present embodiment, resistance R resistance is 50K Ω, and the voltage of the first input power 1 is 15V, the second input power
Voltage is 10V.
In the present embodiment, when the second input power 2 is accessed and the first input power 1 is not accessed, due under resistance R
Drawing, which is acted on, make it that FET Q is in the conduction state, and the second input power 2 is complete by FET Q and Schottky diode D2
Paired power output end VDD power supply；Access or the first input power 1, the second input power 2 behind the first input power 1
When accessing simultaneously, FET Q is in cut-off state, and the first input power 1 completes defeated to power supply by Schottky diode D1
Go out to hold VDD power supply.Schottky diode D1, D2 conducting voltage are smaller and can prevent pouring in down a chimney between power supply.
The present embodiment realizes the automatic switchover of two-way power supply, it is allowed to which two-way power supply is accessed simultaneously, and the first input electricity
Source 1 has higher priority.The double loop power supply automatic switch-over circuit that the present embodiment is provided realizes simple and circuit small volume, institute
It is relatively low with cost.
Although the embodiment of the present invention is the foregoing described, it will be appreciated by those of skill in the art that this is only
For example, protection scope of the present invention is to be defined by the appended claims.Those skilled in the art without departing substantially from
On the premise of the principle and essence of the present invention, various changes or modifications can be made to these embodiments, but these changes and
Modification each falls within protection scope of the present invention.
Claims (7)
1. a kind of double loop power supply automatic switch-over circuit, for switching the first input power and the second input power, it is characterised in that
Including power output end, the first single-way switch, the second single-way switch and three-terminal switch circuit, the three-terminal switch circuit includes the
One end, the second end and the 3rd end；
The first end, the input of first single-way switch and first input power electrical connection, second end with
The second input power electrical connection, the 3rd end is electrically connected with the input of second single-way switch, and described first is single
Electrically connected to the output end of switch, the output end of second single-way switch and the power output end；
The three-terminal switch circuit is used for when accessing second input power and disconnecting first input power so that institute
The second end and the 3rd end conducting are stated, the three-terminal switch circuit is additionally operable to when accessing first input power so that institute
The second end and the 3rd end is stated to disconnect；
First single-way switch subtracts the output of first single-way switch in the input terminal voltage of first single-way switch
The difference of terminal voltage is turned on when being more than the first preset value；
Second single-way switch subtracts the output of second single-way switch in the input terminal voltage of second single-way switch
The difference of terminal voltage is turned on when being more than the second preset value.
2. double loop power supply automatic switch-over circuit as claimed in claim 1, it is characterised in that first single-way switch and described
Second single-way switch is diode.
3. double loop power supply automatic switch-over circuit as claimed in claim 2, it is characterised in that first single-way switch and described
Second single-way switch is Schottky diode.
4. the double loop power supply automatic switch-over circuit as described in any one of claims 1 to 3, it is characterised in that the double loop power supply
Automatic switch-over circuit also includes a resistance, and one end of the resistance is grounded, the other end of the resistance and the described first input electricity
Source is electrically connected；
The three-terminal switch circuit is FET, and the first end is the grid of the FET, and second end is institute
The source electrode of FET is stated, the 3rd end is the drain electrode of the FET.
5. double loop power supply automatic switch-over circuit as claimed in claim 4, it is characterised in that the FET is PMOS.
6. double loop power supply automatic switch-over circuit as claimed in claim 4, it is characterised in that the resistance of the resistance is 1~
100KΩ。
7. double loop power supply automatic switch-over circuit as claimed in claim 4, it is characterised in that the voltage of first input power
For 5~20V；The voltage of second input power is 5~20V.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710457106.8A CN107069945A (en) | 2017-06-16 | 2017-06-16 | Double loop power supply automatic switch-over circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710457106.8A CN107069945A (en) | 2017-06-16 | 2017-06-16 | Double loop power supply automatic switch-over circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN107069945A true CN107069945A (en) | 2017-08-18 |
Family
ID=59594666
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710457106.8A Pending CN107069945A (en) | 2017-06-16 | 2017-06-16 | Double loop power supply automatic switch-over circuit |
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| Country | Link |
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| CN (1) | CN107069945A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202333956U (en) * | 2011-11-02 | 2012-07-11 | 广州曼翔医疗器械有限公司 | Automatic seamless switching type dual-power circuit |
| WO2016031037A1 (en) * | 2014-08-29 | 2016-03-03 | 東芝三菱電機産業システム株式会社 | Inverter |
| CN205355935U (en) * | 2015-12-22 | 2016-06-29 | 上海爱信诺航芯电子科技有限公司 | Dual supply automatic switchover power supply and prevent circuit that power joins conversely |
| US20170094732A1 (en) * | 2015-09-30 | 2017-03-30 | Energizer Brands, Llc | Electronic protection against circuit reversal |
| CN106787129A (en) * | 2016-12-15 | 2017-05-31 | 山东金洲科瑞节能科技有限公司 | A kind of power-supply management system for being automatically obtained main power supply switching |
-
2017
- 2017-06-16 CN CN201710457106.8A patent/CN107069945A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202333956U (en) * | 2011-11-02 | 2012-07-11 | 广州曼翔医疗器械有限公司 | Automatic seamless switching type dual-power circuit |
| WO2016031037A1 (en) * | 2014-08-29 | 2016-03-03 | 東芝三菱電機産業システム株式会社 | Inverter |
| US20170094732A1 (en) * | 2015-09-30 | 2017-03-30 | Energizer Brands, Llc | Electronic protection against circuit reversal |
| CN205355935U (en) * | 2015-12-22 | 2016-06-29 | 上海爱信诺航芯电子科技有限公司 | Dual supply automatic switchover power supply and prevent circuit that power joins conversely |
| CN106787129A (en) * | 2016-12-15 | 2017-05-31 | 山东金洲科瑞节能科技有限公司 | A kind of power-supply management system for being automatically obtained main power supply switching |
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| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20170818 |