CN206209032U - Power failure detection circuit and switching power supply circuit - Google Patents
Power failure detection circuit and switching power supply circuit Download PDFInfo
- Publication number
- CN206209032U CN206209032U CN201621243111.6U CN201621243111U CN206209032U CN 206209032 U CN206209032 U CN 206209032U CN 201621243111 U CN201621243111 U CN 201621243111U CN 206209032 U CN206209032 U CN 206209032U
- Authority
- CN
- China
- Prior art keywords
- power
- connects
- switch pipe
- circuit
- connection
- 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.)
- Active
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 55
- 230000005611 electricity Effects 0.000 claims abstract description 7
- 238000004804 winding Methods 0.000 claims description 34
- 102100039435 C-X-C motif chemokine 17 Human genes 0.000 description 12
- 101000889048 Homo sapiens C-X-C motif chemokine 17 Proteins 0.000 description 12
- 239000003990 capacitor Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000002955 isolation Methods 0.000 description 3
- 238000009795 derivation Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
The utility model discloses a power down detection circuit, include: the power supply protection circuit comprises a power grid input connecting end, a main chip power supply connecting end, a first switching tube, a second switching tube, a third switching tube and a main chip under-voltage protection pin connecting end; the power grid input connecting end is connected with the control end of the first switching tube; the first end of the first switch tube is connected with the control end of the second switch tube, and the second end of the first switch tube is grounded; the main chip power supply connecting end is connected with the control end of a second switching tube, the first end of the second switching tube is connected with the main chip under-voltage protection pin connecting end, and the second end of the second switching tube is grounded; the first end of the second switch tube is also connected with the control end of a third switch tube, the first end of the third switch tube is connected with the main chip under-voltage protection pin connecting end, and the second end of the third switch tube is connected with the control end of the second switch tube. The utility model discloses still disclose an use above-mentioned switch power supply circuit who falls electric detection circuitry. The utility model discloses can in time turn-off the output when falling the electricity to have and turn off self-locking function.
Description
Technical field
The utility model is related to electronic technology field, especially, is related to a kind of power-fail detection circuit and switching power circuit.
Background technology
In field of switch power, booster circuit, when the unexpected power down of power network is got up again, voltage can decline and rise, when
When voltage declines, booster circuit control chip can increase it and drive dutycycle, if now line voltage goes back up to original voltage,
Output can be overshooted.To prevent output from overshooting, when the unexpected power down of power network, it is necessary to be detected to electric network power-fail, once detect
Electric network power-fail drives output it is necessary to shut-off in time.
Have the scheme that output is driven using the shut-off of under-voltage protection pin flip chip in the prior art, but signal shut-off without
Auto-lock function, when causing line voltage to recover, the voltage of under-voltage protection pin recovers, and circuit can restart at once, due to transformer
The storage effect of secondary capacitance, secondary output is not dropped, that is, thorough power down turn-off function is not implemented.
Utility model content
The technical problems to be solved in the utility model is to provide a kind of power-fail detection circuit and switching power circuit, can be
Output is turned off during power down in time, and with shut-off auto-lock function.
In order to solve the above-mentioned technical problem, the utility model embodiment provides a kind of power-fail detection circuit, including：Power network is defeated
Enter power connection end, first switch pipe, second switch pipe, the 3rd switching tube and the master chip under-voltage protection of connection end, master chip to draw
Pin connection end；
The power network input connection end connects the control end of the first switch pipe；The first end of the first switch pipe connects
Connect the control end of the second switch pipe, the second end ground connection of the first switch pipe；
The master chip connection end that powers connects the control end of the second switch pipe, the first end of the second switch pipe
Connect the master chip under-voltage protection pin connection end, the second end ground connection of the second switch pipe；
The first end of the second switch pipe is also connected with the control end of the 3rd switching tube, the first end of the 3rd switching tube
The master chip under-voltage protection pin connection end is connected, the second end of the 3rd switching tube connects the control of the second switch pipe
End processed.
Implement the utility model embodiment, have the advantages that：
The power-fail detection circuit that the utility model embodiment is provided, in electric network power-fail, line voltage is not enough to conducting the
One switching tube, therefore height is put in control end acceptor's chip power supply pin influence of second switch pipe, turns on second switch pipe, makes the
The first end of two switching tubes turns on the 3rd switching tube with low-voltage signal, and the 3rd switching tube is by the biased electrical of chip under-voltage protection pin
Pressure causes the control end of second switch pipe, second switch pipe is further turned on, and forms positive feedback, i.e. self-locking, second switch pipe
Constant conduction then drags down master chip under-voltage protection pin, master chip is turned off output.
Further, the power-fail detection circuit also includes the first bleeder circuit, and first bleeder circuit includes first
Resistance and second resistance；The first end of the first resistor is the input of first bleeder circuit, the first resistor
Second end connects the first end of the second resistance, the second end ground connection of the second resistance, the first end of the second resistance
It is the output end of first bleeder circuit；
The master chip connection end that powers connects the control end of the second switch pipe, specially：The master chip is powered
Connection end connects the control end of the second switch pipe by the first bleeder circuit；Wherein, the input of first bleeder circuit
The end connection master chip is powered connection end, and the output end of first bleeder circuit connects the control of the second switch pipe
End.
Further, the power-fail detection circuit also includes rectification circuit and the second bleeder circuit, the second partial pressure electricity
Road includes 3rd resistor and the 4th resistance, and the first end of the 3rd resistor is the input of second bleeder circuit, described
Second end of 3rd resistor connects the first end of the 4th resistance, the second end ground connection of the 4th resistance, the 4th electricity
The first end of resistance is the output end of second bleeder circuit；
The power network input connection end connects the control end of the first switch pipe, specially：The power network input connection
Hold the control end that the first switch pipe is connected by the rectification circuit and second bleeder circuit；Wherein, the rectification
The positive pole of circuit connects the power network input connection end, and the negative pole of the rectification circuit connects the input of second bleeder circuit
End, the output end of second bleeder circuit connects the control end of the first switch pipe.
Preferably, the first switch pipe is NPN type triode, and the base stage of the NPN type triode is opened for described first
The control end of pass pipe, the first end of the extremely described first switch pipe of current collection of the NPN type triode, the NPN triode
Second end of the extremely described first switch pipe of transmitting.
Preferably, the second switch pipe is NPN type triode, and the base stage of the NPN type triode is opened for described second
The control end of pass pipe, the first end of the extremely described second switch pipe of current collection of the NPN type triode, the NPN triode
Second end of the extremely described second switch pipe of transmitting.
Preferably, the 3rd switching tube is PNP type triode, and the base stage of the PNP triode is the described 3rd switch
The control end of pipe, the first end of extremely described 3rd switching tube of transmitting of the PNP triode, the current collection of the PNP triode
Second end of extremely described 3rd switching tube.
Correspondingly, the utility model embodiment also provides a kind of switching power circuit, including：Master chip, transformer, power network
Incoming end, main switch, power output end and power-fail detection circuit as described above；
The master chip includes energization pins, under-voltage protection pin and drives output pin；The transformer includes primary
Winding, secondary windings and assists winding；
The power network incoming end connects the first end of the armature winding, and the second end of the armature winding connects the master
The first end of switching tube, the second end ground connection of the main switch；The control for driving output pin to connect the main switch
End processed；The secondary windings connects the power output end；
The master chip that the first end of the assists winding connects the power-fail detection circuit is powered connection end, the auxiliary around
The second end ground connection of group；The master chip that the energization pins connect the power-fail detection circuit is powered connection end；
The under-voltage protection pin connects the master chip under-voltage protection pin connection end of the power-fail detection circuit；The electricity
Net incoming end connects the power network input connection end of the power-fail detection circuit.
The switching power circuit that the utility model embodiment is provided, in electric network power-fail, line voltage is not enough to conducting the
One switching tube, therefore height is put in control end acceptor's chip power supply pin influence of second switch pipe, turns on second switch pipe, makes the
The first end of two switching tubes turns on the 3rd switching tube with low-voltage signal, and the 3rd switching tube is by the biased electrical of chip under-voltage protection pin
Pressure causes the control end of second switch pipe, second switch pipe is further turned on, and forms positive feedback, i.e. self-locking, second switch pipe
Constant conduction then drags down master chip under-voltage protection pin, master chip is turned off output.
Further, the switching power circuit also includes the 5th resistance and the first diode；
The master chip that the first end of the assists winding connects the power-fail detection circuit is powered connection end, specially：Institute
The first end for stating assists winding connects the main core of the power-fail detection circuit by the 5th resistance and first diode
Piece is powered connection end；Wherein, the first end of the 5th resistance connects the first end of the assists winding, the 5th resistance
Second end connects the positive pole of first diode, and the negative pole of first diode connects the master chip and powers connection end.
Further, the switching power circuit also includes the 6th resistance and the second diode；
The master chip that the energization pins connect the power-fail detection circuit is powered connection end, specially：The power supply is drawn
Pin is powered connection end by the master chip that second diode and the 6th resistance connect the power-fail detection circuit；Its
In, the negative pole of second diode connects the energization pins, and the positive pole of second diode connects the 6th resistance
First end, the second end of the 6th resistance connects the master chip and powers connection end.
In further scheme, chip power supply pin and power-fail detection circuit are realized by the second diode and the 6th resistance
In second switch pipe isolation, to avoid second switch pipe from vising voltage not reaching chip to start the problem of voltage.
Further, the switching power circuit also includes the 7th resistance；The first end connection of the 7th resistance is described
Power network incoming end, the second end of the 7th resistance connects the energization pins.
Brief description of the drawings
Fig. 1 is the schematic diagram of the one embodiment for the power-fail detection circuit that the utility model is provided；
Fig. 2 is the schematic diagram of the one embodiment for the switching power circuit that the utility model is provided.
Specific embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is carried out
Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the utility model, rather than whole
Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made
The every other embodiment for being obtained, belongs to the scope of the utility model protection.
It is the schematic diagram of the one embodiment for the power-fail detection circuit that the utility model is provided referring to Fig. 1；The present embodiment is carried
For a kind of power-fail detection circuit, including：Power network input connection end, master chip are powered connection end VCC1, first switch pipe Q1, second
Switching tube Q2, the 3rd switching tube Q3 and master chip under-voltage protection pin connection end COMP1；
Power network input connection end connects the control end of first switch pipe Q1；Specifically, power-fail detection circuit also includes rectification
Circuit (including diode D3 and D4) and the second bleeder circuit, the second bleeder circuit include 3rd resistor R3 and the 4th resistance R4,
The first end of 3rd resistor R3 is the input of the second bleeder circuit, and second end of 3rd resistor R3 connects the of the 4th resistance R4
One end, the second end ground connection of the 4th resistance R4, the first end of the 4th resistance R4 is the output end of the second bleeder circuit；Power network is input into
Connection end connects the control end of first switch pipe Q1 by rectification circuit (diode D3 and D4) and the second bleeder circuit；Wherein,
The positive pole connection power network input connection end of rectification circuit, the negative pole of rectification circuit connects the input of the second bleeder circuit, second
The control end of the output end connection first switch pipe Q1 of bleeder circuit；
Control end (preferably, the of first switch pipe Q1 of the first end connection second switch pipe Q2 of first switch pipe Q1
One end connects the control end of second switch pipe Q2 by resistor), the second end ground connection of first switch pipe Q1；
Master chip is powered the control end of connection end VCC1 connections second switch pipe Q2；Specifically, power-fail detection circuit is also wrapped
The first bleeder circuit is included, the first bleeder circuit includes first resistor R1 and second resistance R2；The first end of first resistor R1 is the
The input of one bleeder circuit, second end of first resistor R1 connects the first end of second resistance R2, the second of second resistance R2
End ground connection, the first end of second resistance R2 is the output end of the first bleeder circuit；Master chip powers connection end VCC1 by first
Bleeder circuit connects the control end of second switch pipe；Wherein, the input connection master chip of the first bleeder circuit is powered connection end
VCC1, the control end of the output end connection second switch pipe Q2 of the first bleeder circuit；
The first end connection master chip under-voltage protection pin connection end COMP1 of second switch pipe Q2, second switch pipe Q2's
Second end is grounded；
The first end of second switch pipe Q2 is also connected with the control end of the 3rd switching tube Q3, and the first end of the 3rd switching tube Q3 connects
The second end for meeting master chip under-voltage protection pin connection end COMP1, the 3rd switching tube Q3 connects the control end of second switch pipe Q2.
The power-fail detection circuit that the utility model embodiment is provided, operation principle is as follows：In normal work, line voltage
Height, first switch pipe Q1 conductings, so as to drag down the control end of second switch pipe Q2, prevents it from turning on, and does not influence main circuit
Normal work；In electric network power-fail, line voltage be not enough to turn on first switch pipe Q1, therefore second switch pipe Q2 control end
Height is put in the influence of acceptor's chip power supply pin, turns on second switch pipe Q2, makes the first end of second switch pipe Q2 with low-voltage signal
The 3rd switching tube Q3 is turned on, the bias voltage of chip under-voltage protection pin is caused the 3rd switching tube Q3 the control of second switch pipe Q2
End processed, makes second switch pipe Q2 further turn on, and forms positive feedback, i.e. self-locking, and second switch pipe Q2 constant conductions then drag down master
Chip under-voltage protection pin, makes master chip turn off output.
Preferably, first switch pipe Q1 is NPN type triode, and the base stage of NPN type triode is the control of first switch pipe Q1
End processed, the current collection extremely first end of first switch pipe Q1 of NPN type triode, the transmitting extremely first switch pipe of NPN triode
Second end of Q1.
Preferably, second switch pipe is NPN type triode, and the base stage of NPN type triode is the control of second switch pipe Q2
End, the current collection extremely first end of second switch pipe Q2 of NPN type triode, the transmitting extremely second switch pipe Q2 of NPN triode
The second end.
Preferably, the 3rd switching tube is PNP type triode, and the base stage of PNP triode is the control end of the 3rd switching tube Q3,
The transmitting extremely first end of the 3rd switching tube Q3, the current collection extremely the second of the 3rd switching tube Q3 of PNP triode of PNP triode
End.
Further, power-fail detection circuit also includes the first electric capacity C1, the second electric capacity C2 and the 3rd electric capacity for filtering
C3, wherein, the first end of the first electric capacity C1 connects the output end of second bleeder circuit, the second end ground connection；Second electric capacity C2
First end connection master chip under-voltage protection pin connection end COMP1, the second end connects the first end of the second switch pipe Q2；
The control end of the first end connection second switch pipe Q2 of the 3rd electric capacity C3, the second end ground connection.
It should be noted that in the switching power circuit of above-described embodiment offer, first switch pipe Q1 is the pole of NPN type three
Pipe, second switch pipe Q2 is NPN type triode, and the 3rd switching tube is PNP type triode, a kind of embodiment party only therein
Formula, in other embodiments, first switch pipe Q1 and second switch pipe Q2 may be replaced by N-type FET or other are put
The three ports for control switching device of control end conducting high or its derivation device, the 3rd switching tube Q3 can also replace with p-type field-effect
Manage or other set low three ports for control switching device or its derivation device that control end is turned on, in different application scenarios, depending on reality
The power consumption of border circuit, cost, driving power and with the drive control component parameter matching of switching tube etc. require reasonable selection and
Set, from and set switching tube be prior art conventional design process, do not repeated herein.
Correspondingly, the utility model embodiment also provides a kind of switching power circuit, is that the utility model is carried referring to Fig. 2
The schematic diagram of one embodiment of the switching power circuit of confession.Switching power circuit includes：Master chip U1, transformer T1, power network
Incoming end N, main switch (not shown), power output end (not shown) and power-fail detection circuit as above；
Master chip U1 includes energization pins VCC, under-voltage protection pin COMP and drives output pin GATE；Transformer T1 bags
Include armature winding T1A, secondary windings T1B and assists winding T1C；
Power network incoming end N connects the first end of armature winding, and the second end of armature winding connects the first end of main switch,
The second end ground connection of main switch；Output pin GATE is driven to connect the control end of main switch；Secondary windings T1B connects power supply
Output end；
The master chip of the first end connection power-fail detection circuit of assists winding T1C is powered connection end VCC1, assists winding T1C
The second end ground connection；The master chip of energization pins VCC connection power-fail detection circuits is powered connection end VCC1；
Under-voltage protection pin COMP connects the master chip under-voltage protection pin connection end COMP1 of power-fail detection circuit；Power network
The power network input connection end of incoming end N connection power-fail detection circuits.
Further, switching power circuit also includes the 5th resistance R5 and the first diode D1；
The master chip of the first end connection power-fail detection circuit of assists winding T1C is powered connection end VCC1, specially：Auxiliary
The first end of winding T1C is powered connection end by the master chip that the 5th resistance R2 and the first diode D1 connect power-fail detection circuit
VCC1；Wherein, the first end of the first end connection assists winding T1C of the 5th resistance R5, the second end connection of the 5th resistance R5 the
The positive pole of one diode D1, the negative pole connection master chip of the first diode D1 is powered connection end.
Further, switching power circuit also includes the 6th resistance R6 and the second diode D2；
The master chip of energization pins VCC connection power-fail detection circuits is powered connection end VCC1, specially：Energization pins VCC
The master chip for connecting power-fail detection circuit by the second diode D2 and the 6th resistance R6 is powered connection end VCC1；Wherein, second
The positive pole of negative pole connection the energization pins VCC, the second diode D2 of diode D2 connects the first end of the 6th resistance R6, the 6th electricity
The the second end connection master chip for hindering R6 is powered connection end VCC1.
In further scheme, chip power supply pin VCC and power down are realized by the second diode D2 and the 6th resistance R6
The isolation of the second switch pipe Q2 in detection circuit, chip startup voltage is not reached to avoid second switch pipe Q2 from vising voltage
Problem, in other embodiments, can using other schemes realize isolation.
Further, switching power circuit also includes the 7th resistance；The first end connection power network incoming end of the 7th resistance, the
The second end connection energization pins of seven resistance.7th resistance connects power network incoming end, is the start-up circuit of chip.When access power network
When, first by the high voltage startup chip of power network incoming end, and then driving has output, has electric current to pass through in winding, and assists winding gives
The work of chip stabilization is powered.7th resistance can be made up of the connection in series-parallel assembly of single resistor or multiple resistors, at this
It is the series combination of resistance R7 and resistance R8 in embodiment.
Further, switching power circuit also includes the first electrochemical capacitor EB1 and the second electrochemical capacitor for filtering
EB2, wherein, the first end connection chip power supply pin VCC of the first electrochemical capacitor EB1, the second end ground connection；Second electrochemical capacitor
The first end connection master chip of EB2 is powered connection end VCC1, the second end ground connection.
Power-fail detection circuit and switching power circuit that the utility model embodiment is provided, in electric network power-fail, power network electricity
Pressure is not enough to turn on first switch pipe, therefore height is put in control end acceptor's chip power supply pin influence of second switch pipe, makes second
Switching tube is turned on, and the first end of second switch pipe is turned on the 3rd switching tube with low-voltage signal, and the 3rd switching tube is under-voltage by chip
The bias voltage of protection pin causes the control end of second switch pipe, second switch pipe is further turned on, and forms positive feedback, i.e.,
Self-locking, second switch pipe constant conduction then drags down master chip under-voltage protection pin, master chip is turned off output.
Above is preferred embodiment of the present utility model, it is noted that for those skilled in the art
For, on the premise of the utility model principle is not departed from, some improvement and deformation can also be made, these improve and deform
It is considered as protection domain of the present utility model.
Claims (10)
1. a kind of power-fail detection circuit, it is characterised in that including：Power network input connection end, master chip power connection end, first open
Guan Guan, second switch pipe, the 3rd switching tube and master chip under-voltage protection pin connection end；
The power network input connection end connects the control end of the first switch pipe；The first end connection institute of the first switch pipe
State the control end of second switch pipe, the second end ground connection of the first switch pipe；
The master chip connection end that powers connects the control end of the second switch pipe, the first end connection of the second switch pipe
The master chip under-voltage protection pin connection end, the second end ground connection of the second switch pipe；
The first end of the second switch pipe is also connected with the control end of the 3rd switching tube, the first end connection of the 3rd switching tube
The master chip under-voltage protection pin connection end, the second end of the 3rd switching tube connects the control of the second switch pipe
End.
2. power-fail detection circuit as claimed in claim 1, it is characterised in that the power-fail detection circuit also includes the first partial pressure
Circuit, first bleeder circuit includes first resistor and second resistance；The first end of the first resistor is described first point
The input of volt circuit, the second end of the first resistor connects the first end of the second resistance, and the of the second resistance
Two ends are grounded, and the first end of the second resistance is the output end of first bleeder circuit；
The master chip connection end that powers connects the control end of the second switch pipe, specially：The master chip is powered connection
End connects the control end of the second switch pipe by the first bleeder circuit；Wherein, the input of first bleeder circuit connects
Connect the master chip to power connection end, the output end of first bleeder circuit connects the control end of the second switch pipe.
3. power-fail detection circuit as claimed in claim 1, it is characterised in that the power-fail detection circuit also includes rectification circuit
With the second bleeder circuit, second bleeder circuit includes 3rd resistor and the 4th resistance, and the first end of the 3rd resistor is
The input of second bleeder circuit, the second end of the 3rd resistor connects the first end of the 4th resistance, and described the
The second end ground connection of four resistance, the first end of the 4th resistance is the output end of second bleeder circuit；
The power network input connection end connects the control end of the first switch pipe, specially：The power network input connection end leads to
Cross the rectification circuit and second bleeder circuit connects the control end of the first switch pipe；Wherein, the rectification circuit
Positive pole connect power network input connection end, the negative pole of the rectification circuit connects the input of second bleeder circuit,
The output end of second bleeder circuit connects the control end of the first switch pipe.
4. power-fail detection circuit as claimed in claim 1, it is characterised in that the first switch pipe is NPN type triode, institute
The base stage for stating NPN type triode is the control end of the first switch pipe, the current collection extremely described first of the NPN type triode
The first end of switching tube, the second end of the extremely described first switch pipe of transmitting of the NPN triode.
5. power-fail detection circuit as claimed in claim 1, it is characterised in that the second switch pipe is NPN type triode, institute
The base stage for stating NPN type triode is the control end of the second switch pipe, the current collection extremely described second of the NPN type triode
The first end of switching tube, the second end of the extremely described second switch pipe of transmitting of the NPN triode.
6. power-fail detection circuit as claimed in claim 1, it is characterised in that the 3rd switching tube is PNP type triode, institute
The base stage for stating PNP triode is the control end of the 3rd switching tube, extremely described 3rd switch of transmitting of the PNP triode
The first end of pipe, the second end of extremely described 3rd switching tube of current collection of the PNP triode.
7. a kind of switching power circuit, it is characterised in that including：Master chip, transformer, power network incoming end, main switch, power supply
Output end and the power-fail detection circuit as described in any one of claim 1 to 6；
The master chip includes energization pins, under-voltage protection pin and drives output pin；The transformer include armature winding,
Secondary windings and assists winding；
The power network incoming end connects the first end of the armature winding, and the second end of the armature winding connects the main switch
The first end of pipe, the second end ground connection of the main switch；The control end for driving output pin to connect the main switch；
The secondary windings connects the power output end；
The master chip that the first end of the assists winding connects the power-fail detection circuit is powered connection end, the assists winding
Second end is grounded；The master chip that the energization pins connect the power-fail detection circuit is powered connection end；
The under-voltage protection pin connects the master chip under-voltage protection pin connection end of the power-fail detection circuit；The power network connects
Enter the power network input connection end of the end connection power-fail detection circuit.
8. switching power circuit as claimed in claim 7, it is characterised in that the switching power circuit also includes the 5th resistance
With the first diode；
The master chip that the first end of the assists winding connects the power-fail detection circuit is powered connection end, specially：It is described auxiliary
The first end of winding is helped to be supplied by the master chip that the 5th resistance and first diode connect the power-fail detection circuit
Electric connecting terminal；Wherein, the first end of the 5th resistance connects the first end of the assists winding, the second of the 5th resistance
The positive pole of end connection first diode, the negative pole of first diode connects the master chip and powers connection end.
9. switching power circuit as claimed in claim 7, it is characterised in that the switching power circuit also includes the 6th resistance
With the second diode；
The master chip that the energization pins connect the power-fail detection circuit is powered connection end, specially：The energization pins are led to
Cross second diode and the 6th resistance and connect the master chip of the power-fail detection circuit and power connection end；Wherein, institute
The negative pole for stating the second diode connects the energization pins, and the positive pole of second diode connects the first of the 6th resistance
End, the second end of the 6th resistance connects the master chip and powers connection end.
10. switching power circuit as claimed in claim 7, it is characterised in that the switching power circuit also includes the 7th electricity
Resistance；The first end of the 7th resistance connects the power network incoming end, and the second end connection power supply of the 7th resistance is drawn
Pin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621243111.6U CN206209032U (en) | 2016-11-15 | 2016-11-15 | Power failure detection circuit and switching power supply circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621243111.6U CN206209032U (en) | 2016-11-15 | 2016-11-15 | Power failure detection circuit and switching power supply circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206209032U true CN206209032U (en) | 2017-05-31 |
Family
ID=58749639
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621243111.6U Active CN206209032U (en) | 2016-11-15 | 2016-11-15 | Power failure detection circuit and switching power supply circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206209032U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109104091A (en) * | 2018-08-13 | 2018-12-28 | 深圳市普威技术有限公司 | A kind of power circuit and power supply adaptor |
| CN109738831A (en) * | 2018-12-04 | 2019-05-10 | 广州市扬新技术研究有限责任公司 | A kind of electrical two self-locking station pressure-adjusting type Switching Power Supply wiring board detection circuits of band |
| CN113922655A (en) * | 2021-10-18 | 2022-01-11 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starts and loses electric warning circuit and switching power supply |
-
2016
- 2016-11-15 CN CN201621243111.6U patent/CN206209032U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109104091A (en) * | 2018-08-13 | 2018-12-28 | 深圳市普威技术有限公司 | A kind of power circuit and power supply adaptor |
| CN109738831A (en) * | 2018-12-04 | 2019-05-10 | 广州市扬新技术研究有限责任公司 | A kind of electrical two self-locking station pressure-adjusting type Switching Power Supply wiring board detection circuits of band |
| CN113922655A (en) * | 2021-10-18 | 2022-01-11 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starts and loses electric warning circuit and switching power supply |
| CN113922655B (en) * | 2021-10-18 | 2024-02-20 | 无锡市欧瑞杰电子科技有限公司 | PWM chip starting and power-off alarm circuit and switching power supply |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN206321756U (en) | Power failure detection circuit and switching power supply circuit | |
| CN206209032U (en) | Power failure detection circuit and switching power supply circuit | |
| CN205070791U (en) | Switching power supply from supply circuit | |
| CN103560675B (en) | A kind of power supply output control circuit and multilamellar electric supply system | |
| CN106992668A (en) | A kind of alternating current-direct current Mixed design dc source | |
| CN206932172U (en) | A kind of power supply and its self discharge control circuit | |
| CN203632222U (en) | Output short circuit protection circuit of flyback converter | |
| CN206619904U (en) | A kind of battery reversal connection leakproof current circuit | |
| CN215934520U (en) | Power supply switching system and dual-power supply equipment | |
| CN104953541B (en) | A kind of overvoltage protection | |
| CN112265473B (en) | Driving device | |
| CN208862634U (en) | A kind of power supply switching power supply circuit | |
| CN207265858U (en) | A kind of phase whole-bridging circuit of gamut Sofe Switch | |
| CN203180779U (en) | Switch power supply provided with output short circuit protection function | |
| CN207304498U (en) | A kind of inverse E class power amplification circuits | |
| CN206481243U (en) | A kind of switch reluctance machine drive silicon controlled control circuit | |
| CN102044379B (en) | Relay control device | |
| CN205753352U (en) | Servo-driver dual power supply low pressure sync detection circuit | |
| CN205069083U (en) | Overshoot prevention circuit | |
| CN204089154U (en) | The overvoltage crowbar of a kind of ultra-high-tension power transmission line ground wire power taking | |
| CN206992680U (en) | Undervoltage protection circuit | |
| CN208835796U (en) | Switching circuit of power supply | |
| CN103490388B (en) | A kind of overvoltage and under-voltage protecting circuit | |
| CN206481221U (en) | Inverse-excitation type switch power-supply | |
| CN201219234Y (en) | Resonance driving module with dynamic power supply |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |