CN209488160U - A kind of input over under-voltage protection circuit and appliances power source - Google Patents
A kind of input over under-voltage protection circuit and appliances power source Download PDFInfo
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- CN209488160U CN209488160U CN201822089843.XU CN201822089843U CN209488160U CN 209488160 U CN209488160 U CN 209488160U CN 201822089843 U CN201822089843 U CN 201822089843U CN 209488160 U CN209488160 U CN 209488160U
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Abstract
The utility model provides a kind of input over under-voltage protection circuit and appliances power source; the input over under-voltage protection circuit includes rectification circuit, under-voltage protecting circuit, overvoltage crowbar and power supply chip; the input terminal of rectification circuit accesses alternating current; its output end is connected with the input terminal of under-voltage protecting circuit, overvoltage crowbar, and rectification circuit is used to AC conversion be low-voltage DC；Under-voltage protecting circuit exports a low level signal when the low-voltage DC is lower than under-voltage protection value, so that appliances power source is out of service for receiving the low-voltage DC；Overvoltage crowbar exports a low level signal when the low-voltage DC is higher than overvoltage protection value, so that appliances power source is out of service for receiving the low-voltage DC.The input over under-voltage protection circuit can protect the element in appliance circuit in the input overvoltage/undervoltage of appliance circuit, improve the stability and service life of appliance circuit；And circuit structure is simple, has saved cost.
Description
Technical field
The utility model relates to protect field of circuit technology, in particular to a kind of input over under-voltage protection circuit and electric appliance electricity
Source.
Background technique
Various electric appliances in life often have different degrees of damage because of the exception of use environment in practical applications, input
Overvoltage/undervoltage is one of more typical destructive factor.Input overvoltage/undervoltage will lead to inside electric appliance occur control loop it is unstable,
The abnormal conditions such as power device overheat, magnetic device saturation, easily cause electric appliance damage.
Utility model content
In view of this, the utility model is directed to a kind of input over under-voltage protection circuit, to solve the input of electric appliance
The problem of under-voltage electric appliance easy to damage.
In order to achieve the above objectives, the technical solution of the utility model is achieved in that
A kind of input over under-voltage protection circuit, including rectification circuit, under-voltage protecting circuit and overvoltage crowbar,
In:
The input terminal of the rectification circuit accesses alternating current, and output end and the under-voltage protecting circuit, the over-voltage are protected
The input terminal of protection circuit is connected, and the rectification circuit is used to AC conversion be low-voltage DC；
The under-voltage protecting circuit is for receiving the low-voltage DC and controlling institute when the low-voltage DC is under-voltage
It states power supply chip and closes driving output, the overvoltage crowbar is for detecting the low-voltage DC and in the low-voltage direct
The power supply chip is controlled when electric over-voltage closes driving output.
Further, the rectification circuit includes rectifier bridge, first resistor and second resistance, the direct current of the rectifier bridge
Side anode is successively grounded through the first resistor, the second resistance, the common end work of the first resistor, the second resistance
For the output end of the rectification circuit.
Further, the rectification circuit further includes electrolytic capacitor, and the DC side anode of the rectifier bridge is through the electrolysis
Capacity earth.
Further, the under-voltage protecting circuit includes first diode, the first triode, the second triode and third
The output end of resistance, the rectification circuit is connected through the first diode with the ground level of first triode, and described first
The collector of triode is connected with the ground level of second triode, the collector of first triode, the two or three pole
The common end of the ground level of pipe is connected through the 3rd resistor with the DC side anode of the rectifier bridge, first triode, institute
The emitter for stating the second triode is grounded, and the collector of second triode is connected with the power supply chip.
Further, the under-voltage protecting circuit further includes the second diode, the cathode of second diode with it is described
The collector of first triode is connected, and anode is connected with the emitter of first triode.
Further, the under-voltage protecting circuit further includes third diode, the first diode, the one or three pole
The common end of pipe ground level is connected through the third diode with the collector of second triode.
Further, the under-voltage protecting circuit further includes the 4th diode, the collection of cathode and second triode
Electrode is connected, the output end of the just extremely described under-voltage protecting circuit (20).
Further, the under-voltage protecting circuit further includes the 4th resistance, the 3rd resistor, the first triode collection
The common end of electrode is connected through the 4th resistance with the ground level of second triode.
Further, the overvoltage crowbar include the 5th diode and third transistor, the rectification circuit it is defeated
Outlet is connected through the 5th diode with the ground level of the third transistor, the emitter ground connection of the third transistor,
Collector is connected with the collector of second triode.
Compared with the existing technology, input over under-voltage protection circuit described in the utility model has the advantage that
In input over under-voltage protection circuit described in the utility model, when the input undervoltage of electric appliance, under-voltage protecting circuit
The low-voltage DC for being lower than under-voltage protection value is received, a low level is exported, so that appliances power source is out of service；When the input of electric appliance
When over-voltage, overvoltage crowbar receives the low-voltage DC for being higher than overvoltage protection value, a low level is exported, so that appliances power source stops
Only run.In this way, the input over under-voltage protection circuit protects the element in appliance circuit in the input overvoltage/undervoltage of electric appliance,
Improve the stability and service life of appliance circuit；And circuit structure is simple, without using comparator as core element, section
About cost.
The another object of the utility model is to provide a kind of appliances power source, easy to damage with the input overvoltage/undervoltage for solving electric appliance
The problem of electric appliance.
In order to achieve the above objectives, the technical solution of the utility model is achieved in that
A kind of appliances power source, including any of the above-described input over under-voltage protection circuit.
Possessed advantage is similar compared with the existing technology with above-mentioned input over under-voltage protection circuit for the appliances power source,
This is repeated no more.
Detailed description of the invention
The attached drawing for constituting a part of the utility model is used to provide a further understanding of the present invention, this is practical new
The illustrative embodiments and their description of type are not constituteed improper limits to the present invention for explaining the utility model.?
In attached drawing:
Fig. 1 is the schematic diagram that over under-voltage protection circuit is inputted described in the utility model embodiment；
Fig. 2 is the circuit diagram that over under-voltage protection circuit is inputted described in the utility model embodiment.
Description of symbols:
10- rectification circuit, 20- under-voltage protecting circuit, 30- overvoltage crowbar, IC- power supply chip, the one or three pole Q1-
Pipe, the second triode of Q2-, Q3- third transistor, ZD1- first diode, the second diode of ZD2-, D3- third diode,
The 4th diode of D4-, the 5th diode of ZD5-, R1- first resistor, R2- second resistance, R3- 3rd resistor, the 4th resistance of R4-,
The 5th resistance of R5-, the 6th resistance of R6-, the 7th resistance of R7-, the 8th resistance of R8-, the 9th resistance of R9-, E1- electrolytic capacitor, C1-
One capacitor, the second capacitor of C2-, C3- third capacitor, DB1- rectifier bridge.
Specific embodiment
It should be noted that in the absence of conflict, the feature in the embodiments of the present invention and embodiment can
To be combined with each other.
The utility model will be described in detail below with reference to the accompanying drawings and embodiments.
Embodiment 1
As shown in Figure 1, its schematic diagram for input over under-voltage protection circuit in the present embodiment；Wherein, described inputted is owed
Voltage protection circuit includes rectification circuit 10, under-voltage protecting circuit 20 and overvoltage crowbar 30, the rectification circuit 10 it is defeated
Enter to terminate into alternating current, output end is connected with the input terminal of the under-voltage protecting circuit 20, the overvoltage crowbar 30, institute
Rectification circuit 10 is stated for being low-voltage DC by AC conversion；The under-voltage protecting circuit 20 is for receiving the low-pressure direct
Galvanic electricity exports a low level signal when the low-voltage DC is lower than under-voltage protection value, so that appliances power source is out of service；Institute
Overvoltage crowbar 30 is stated for receiving the low-voltage DC, exports one when the low-voltage DC is higher than overvoltage protection value
Low level signal, so that appliances power source is out of service.
In the present embodiment, electric appliance pre-sets brownout threshold, under-voltage protection value, overvoltage threshold and overvoltage protection value.
When the exchange input undervoltage of electric appliance, AC-input voltage is lower than brownout threshold, and the output voltage of rectification circuit 10 is lower than under-voltage
Protection value, the output voltage input undervoltage protection circuit 20 of rectification circuit 10, under-voltage protecting circuit 20 export a low level signal,
So that the power supply of electric appliance is out of service.When the exchange of electric appliance inputs over-voltage, AC-input voltage is higher than overvoltage threshold, rectified current
The output voltage on road 10 is higher than overvoltage protection value, the output voltage protection circuit against input over-voltage 30 of rectification circuit 10, overvoltage protection
Circuit 30 exports a low level signal, so that the power supply of electric appliance is out of service.
In this way, the input over under-voltage protection circuit in the present embodiment can control electricity in time when the input overvoltage/undervoltage of electric appliance
The power supply of device is out of service, avoids electric appliance input overvoltage/undervoltage from causing the damage of electric appliance internal circuit, protects in appliance circuit
Element improves the stability and service life of electric appliance internal circuit.
Further, the power supply of the electric appliance includes power supply chip IC, the under-voltage protecting circuit 20, the overvoltage protection
The output end of circuit 30 is connected with the power supply chip IC.Power supply chip IC is used to control the operating status of appliances power source, when
When the exchange input undervoltage of electric appliance or over-voltage, under-voltage protecting circuit 20 or overvoltage crowbar 30 export a low level to power supply core
Piece IC, control power supply chip IC close driving output, and appliances power source is out of service, and then electric appliance is out of service.
Embodiment 2
Input over under-voltage protection circuit as described above, the present embodiment are different from place and are, as shown in connection with fig. 2,
The rectification circuit 10 includes rectifier bridge DB1, first resistor R1 and second resistance R2, and the DC side of the rectifier bridge DB1 is just
Pole successively through the first resistor R1, the second resistance R2 be grounded, the first resistor R1, the second resistance R2 it is public
Hold the output end as the rectification circuit 10.
When electric appliance is powered, since High Level AC Voltage is difficult to directly detect, it usually needs convert low pressure for High Level AC Voltage
Direct current.In the present embodiment, High Level AC Voltage is converted high voltage direct current by rectifier bridge DB1, and high voltage direct current is through first resistor
Low-voltage DC is converted into after R1 and second resistance R2 partial pressure and is delivered to under-voltage protecting circuit 20 and overvoltage crowbar 30.
In this way, the rectification circuit 10 of the present embodiment can convert low-voltage DC for the High Level AC Voltage for inputting electric appliance, just
The input voltage of electric appliance is detected in under-voltage protecting circuit 20 and overvoltage crowbar 30, and circuit structure is simple, cost is relatively low.
Further, the rectification circuit 10 further includes electrolytic capacitor E1, and the DC side anode of the rectifier bridge DB1 is through institute
State electrolytic capacitor E1 ground connection.Electrolytic capacitor E1 is to reduce AC ripple ripple coefficient, smooth direct current output.
Further, the rectification circuit 10 further includes the second capacitor C2, the second capacitor C2 in parallel with second resistance R2.The
Two capacitor C2 are filtered the output voltage of rectification circuit 10, obtain more stable output voltage, make circuit work more
Stablize.
Embodiment 3
Input over under-voltage protection circuit as described above, the present embodiment are different from place and are, as shown in connection with fig. 2,
The under-voltage protecting circuit 20 includes first diode ZD1, the first triode Q1, the second triode Q2 and 3rd resistor R3,
The output end of the rectification circuit 10 is connected through the first diode ZD1 with the ground level of the first triode Q1, and described
The collector of one triode Q1 is connected with the ground level of the second triode Q2, the collector of the first triode Q1, described
The common end of the ground level of second triode Q2 is connected through the 3rd resistor R3 with the DC side anode of the rectifier bridge DB1, institute
State the first triode Q1, the emitter of the second triode Q2 is grounded.
Wherein, the anode of first diode ZD1 is directly connected by conducting wire with the ground level of the first triode Q1, cathode and
The output end of rectification circuit 10 is connected；The output end of the current collection of second triode Q2 extremely under-voltage protecting circuit 20；One or two pole
Pipe ZD1 is zener diode, the parameter of first diode ZD1 are as follows: when the output voltage of rectification circuit 10 is lower than under-voltage protection value
When, first diode ZD1 is not turned on.In the present embodiment, when the input undervoltage of electric appliance, the output voltage of rectification circuit 10 is lower than
Under-voltage protection value, first diode ZD1 are in off state, and the ground level current potential of the first triode Q1 is low level, the one or three pole
Pipe Q1 is in an off state.The direct current output of rectifier bridge DB1 is loaded into the ground level of the second triode Q2 through 3rd resistor R3, and second
Triode Q2 conducting, the grounded collector of the second triode Q2, and then under-voltage protecting circuit 20 exports a low level signal, electric appliance
Power supply it is out of service.Wherein, 3rd resistor R3 is current-limiting resistance, avoids the excessive triode burnt in circuit of electric current.
In this way, the under-voltage protecting circuit 20 in the present embodiment can control power supply chip IC closing in the input undervoltage of electric appliance
Driving output, and then keep the power supply of electric appliance out of service, it avoids electric appliance input undervoltage from causing the damage of electric appliance internal circuit, protects
Element in appliance circuit, improves the stability and service life of electric appliance internal circuit.And existing input undervoltage protection
Circuit 20 is mostly built with comparator, and since comparator power supply needs additional accessory power supply, such circuit is generally relatively more multiple
It is miscellaneous, higher cost, core element of the input undervoltage protection circuit 20 without using comparator as circuit in this implementation, also without
External power supply is needed to power, circuit structure is simple, has saved cost.
Further, the collector of the second triode Q2 is connected with the protection pin of power supply chip IC, as power supply chip IC
When the level of protection pin is pulled low, power supply chip IC closes driving output.Thus when the input undervoltage of electric appliance, power supply chip
The protection pin of IC is grounded through the second triode Q2, and the level of power supply chip IC protection pin is pulled low, and power supply chip IC is closed
Driving output.And then the under-voltage protecting circuit 20 in the present embodiment directly drags down power supply chip IC protection in electric appliance input undervoltage
The level of pin, without additional control switch between under-voltage protecting circuit 20 and power supply chip IC, the speed of under-voltage protection faster,
Protecting effect is more preferable, and cost is relatively low.Further, the under-voltage protecting circuit 20 further includes the second diode ZD2, and described
The cathode of two diode ZD2 is connected with the collector of the first triode Q1, the hair of anode and the first triode Q1
Emitter-base bandgap grading is connected.Second diode ZD2 is zener diode, carries out pressure stabilizing to the voltage for being loaded into the second triode Q2 ground level, keeps away
Exempt from overtension and damages the second triode Q2.
Further, the under-voltage protecting circuit 20 further includes third diode D3, the first diode ZD1, described
The common end of first triode Q1 ground level is connected through the third diode D3 with the collector of the second triode Q2.
Specifically, the common end of first diode ZD1, the first triode Q1 ground level by conducting wire directly with third diode
The anode of D3 is connected, and the cathode of third diode D3 is connected with the collector of the second triode Q2.Third diode D3 is unidirectional
Freewheeling diode can prevent electric current from flowing backward, and branch where third diode D3 also avoids the outstanding of the second triode Q2 collector
Sky reduces interference.
Further, the under-voltage protecting circuit 20 further includes the 4th diode D4, cathode and second triode
The collector of Q2 is connected, the output end of the just extremely described under-voltage protecting circuit (20).
Specifically, the anode of the 4th diode D4 is connected with power supply chip IC, the current collection of cathode and the second triode Q2
Extremely it is connected.4th diode D4 is unidirectional freewheeling diode, can prevent electric current from flowing backward, play isolated power supply chip IC and preposition electricity
The effect on road.
Further, the under-voltage protecting circuit 20 further includes the 4th resistance R4, the 3rd resistor R3, the described 1st
The common end of pole pipe Q1 collector is connected through the 4th resistance R4 with the ground level of the second triode Q2.4th resistance R4 is
Current-limiting resistance avoids the electric current of the second triode Q2 ground level is excessive from damaging to the second triode Q2.
Further, the under-voltage protecting circuit 20 further includes first capacitor C1, and one end of the 4th resistance R4 is through institute
First capacitor C1 is stated to be connected with the other end of the 4th resistance R4.
First capacitor C1 is in parallel with the 4th resistance R4, when the base voltage of the second triode Q2 is jumped from low level to high level
When change, first capacitor C1 instantaneous short circuit quickly provides base current for the second triode Q2, accelerates leading for the second triode Q2
It is logical.When the base voltage of the second triode Q2 is jumped from high level to low level, first capacitor C1 also instantaneous short circuit, to discharge
The charge of second triode Q2 base stage provides a low impedance path, accelerates the shutdown of the second triode Q2.
In this way, the turn-on and turn-off speed of the second triode Q2 can be improved in first capacitor C1, and then improve under-voltage protection electricity
The protection speed on road 20.
Further, the under-voltage protecting circuit 20 further includes the 5th resistance R5 and the 6th resistance R6, first diode ZD1
It is connected through the 5th resistance R5 with the ground level of the first triode Q1, instead of first diode ZD1 in above-described embodiment and the one or three pole
Conducting wire connection between pipe Q1；First diode ZD1, the 5th resistance R5 common end through third diode D3 and the second triode
The collector of Q2 is connected, instead of " the common end the of first diode ZD1, the first triode Q1 ground level in above-described embodiment
Three diode D3 are connected with the collector of the second triode Q2 ".The 6th electricity of common end of 5th resistance R5, the first triode Q1
Hinder R6 ground connection.5th resistance R5 and the 6th resistance R6 avoids the bias voltage of the first triode Q1 emitter junction as divider resistance
It is excessively high, play the role of protecting the first triode Q1.
Further, the under-voltage protecting circuit 20 further includes the 7th resistance R7, first diode ZD1, the 5th resistance R5
Common end be successively connected through the 7th resistance R7, third diode D3 with the collector of the second triode Q2, instead of above-mentioned implementation
Conducting wire connection in example between first diode ZD1, the common end of the 5th resistance R5 and third diode D3.7th resistance R7 makees
For current-limiting resistance, play the role of protecting third diode D3.
Embodiment 4
Input over under-voltage protection circuit as described above, the present embodiment are different from place and are, as shown in connection with fig. 2,
The overvoltage crowbar 30 includes the 5th diode ZD5 and third transistor Q3, and the output end of the rectification circuit 10 is through institute
It states the 5th diode ZD5 to be connected with the ground level of the third transistor Q3, the emitter ground connection of the third transistor Q3, collection
Electrode is connected with the collector of second triode (Q2).
Wherein, the anode of the 5th diode ZD5 is directly connected by conducting wire with the ground level of third transistor Q3, cathode and
The output end of rectification circuit 10 is connected；5th diode ZD5 is zener diode, the parameter of the 5th diode ZD5 are as follows: work as rectification
When the output voltage of circuit 10 is higher than overvoltage protection value, the 5th diode ZD5 conducting.In the present embodiment, when the input of electric appliance
When pressure, the output voltage of rectification circuit 10 is higher than overvoltage protection value, and the 5th diode ZD5 is in the conductive state, third transistor
The ground level current potential of Q3 be high level, third transistor Q3 conducting, the protection pin of power supply chip IC successively through the 4th diode D4,
Third transistor Q3 ground connection, the level of power supply chip IC protection pin are pulled low, and power supply chip IC closes driving output.
In this way, the overvoltage crowbar 30 in the present embodiment can control power supply chip IC closing in the input over-voltage of electric appliance
Driving output, and then keep the power supply of electric appliance out of service, avoid electric appliance input over-voltage from causing the damage of electric appliance internal circuit, protection
Element in appliance circuit, improves the stability and service life of electric appliance internal circuit.And existing input overvoltage protection
Circuit 30 is mostly built with comparator, and since comparator power supply needs additional accessory power supply, such circuit is generally relatively more multiple
It is miscellaneous, higher cost, core element of the protection circuit against input over-voltage 30 without using comparator as circuit in this implementation, also without
External power supply is needed to power, circuit structure is simple, has saved cost.And the overvoltage crowbar 30 in the present embodiment is inputted in electric appliance
The level that power supply chip IC protection pin is directly dragged down when over-voltage, without additional between overvoltage crowbar 30 and power supply chip IC
Control switch, faster, protecting effect is more preferable for the speed of under-voltage protection, and cost is relatively low.
Further, the overvoltage crowbar 30 further includes the 8th resistance R8 and the 9th resistance R9, the 5th diode ZD5
It is connected through the 8th resistance R8 with the ground level of third transistor Q3, instead of the 5th diode ZD5 and the three or three pole in above-described embodiment
Conducting wire connection between pipe Q3 ground level；The 9th resistance R9 of the common end ground connection of 8th resistance R8, third transistor Q3 ground level.The
Eight resistance R8 and the 9th resistance R9 avoid the bias voltage of third transistor Q3 emitter junction excessively high, play guarantor as divider resistance
Protect the effect of third transistor Q3.
Further, the overvoltage crowbar 30 further include third capacitor C3, third capacitor C3 and the 9th resistance R9 simultaneously
Connection.Noise jamming of the third capacitor C3 as filter capacitor, in filtering circuit.
It should be noted that preferably the first triode Q1, the second triode Q2 and third transistor in above-described embodiment
Q3 is NPN type triode, and the input over under-voltage protection circuit is after simply connecting transformation, the first triode Q1,
Two triode Q2 and third transistor Q3 can also be PNP type triode, can also be NPN type triode, the group of PNP type triode
It closes, circuit has no substantial difference in the change of circuit structure caused by triode type selecting difference and the present embodiment.
Further, in the appliance circuit of part, it is also possible to which field-effect tube replaces the triode in circuit, can reach identical
Protecting effect, thus caused by circuit structure change and the present embodiment in circuit have no substantial difference, repeat no more.
Embodiment 5
The present embodiment provides a kind of appliances power sources, including input over under-voltage protection circuit described in any of the above-described embodiment.
The appliances power source can protect the element in appliance circuit in the input overvoltage/undervoltage of appliance circuit, improve the steady of appliance circuit
Qualitative and service life；And circuit structure is simple, has saved cost.
The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this
Within the spirit and principle of utility model, any modification, equivalent replacement, improvement and so on should be included in the utility model
Protection scope within.
Claims (10)
1. a kind of input over under-voltage protection circuit, which is characterized in that including rectification circuit (10), under-voltage protecting circuit (20) and
Overvoltage crowbar (30), in which:
The input terminal of the rectification circuit (10) is for accessing alternating current, output end and the under-voltage protecting circuit (20), institute
The input terminal for stating overvoltage crowbar (30) is connected, and the rectification circuit (10) is used to AC conversion be low-voltage DC；
The under-voltage protecting circuit (20) is lower than under-voltage protection value for receiving the low-voltage DC, in the low-voltage DC
When export a low level signal so that appliances power source is out of service；The overvoltage crowbar (30) is for receiving the low pressure
Direct current exports a low level signal when the low-voltage DC is higher than overvoltage protection value, so that appliances power source is out of service.
2. input over under-voltage protection circuit according to claim 1, which is characterized in that the rectification circuit (10) includes whole
Bridge (DB1), first resistor (R1) and second resistance (R2) are flowed, the DC side anode of the rectifier bridge (DB1) successively passes through described
First resistor (R1), the second resistance (R2) ground connection, the first resistor (R1), the second resistance (R2) common end make
For the output end of the rectification circuit (10).
3. input over under-voltage protection circuit according to claim 2, which is characterized in that the rectification circuit (10) further includes
The DC side anode of electrolytic capacitor (E1), the rectifier bridge (DB1) is grounded through the electrolytic capacitor (E1).
4. input over under-voltage protection circuit according to claim 2, which is characterized in that under-voltage protecting circuit (20) packet
Include first diode (ZD1), the first triode (Q1), the second triode (Q2) and 3rd resistor (R3), the rectification circuit
(10) output end is connected through the first diode (ZD1) with the ground level of first triode (Q1), the one or three pole
The collector of pipe (Q1) is connected with the ground level of second triode (Q2), the collector of first triode (Q1), described
DC side anode phase of the common end of the ground level of second triode (Q2) through the 3rd resistor (R3) with the rectifier bridge (DB1)
Even, first triode (Q1), second triode (Q2) emitter be grounded.
5. input over under-voltage protection circuit according to claim 4, which is characterized in that the under-voltage protecting circuit (20) is also
Including the second diode (ZD2), the collector phase of the cathode of second diode (ZD2) and first triode (Q1)
Even, anode is connected with the emitter of first triode (Q1).
6. input over under-voltage protection circuit according to claim 4, which is characterized in that the under-voltage protecting circuit (20) is also
Including third diode (D3), the first diode (ZD1), first triode (Q1) ground level common end through described
Three diodes (D3) are connected with the collector of second triode (Q2).
7. input over under-voltage protection circuit according to claim 4, which is characterized in that the under-voltage protecting circuit (20) is also
Including the 4th diode (D4), cathode is connected with the collector of second triode (Q2), the just extremely described under-voltage guarantor
The output end of protection circuit (20).
8. input over under-voltage protection circuit according to claim 4, which is characterized in that the under-voltage protecting circuit (20) is also
Including the 4th resistance (R4), the 3rd resistor (R3), first triode (Q1) collector common end through the described 4th
Resistance (R4) is connected with the ground level of second triode (Q2).
9. according to any input over under-voltage protection circuit of claim 4-8, which is characterized in that the overvoltage crowbar
It (30) include the 5th diode (ZD5) and third transistor (Q3), the output end of the rectification circuit (10) is through the described 5th 2
Pole pipe (ZD5) is connected with the ground level of the third transistor (Q3), the emitter ground connection of the third transistor (Q3), current collection
Pole is connected with the collector of second triode (Q2).
10. a kind of appliances power source, which is characterized in that including the input over under-voltage protection circuit as described in claim 1-9 is any.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822089843.XU CN209488160U (en) | 2018-12-12 | 2018-12-12 | A kind of input over under-voltage protection circuit and appliances power source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201822089843.XU CN209488160U (en) | 2018-12-12 | 2018-12-12 | A kind of input over under-voltage protection circuit and appliances power source |
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| Publication Number | Publication Date |
|---|---|
| CN209488160U true CN209488160U (en) | 2019-10-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201822089843.XU Active CN209488160U (en) | 2018-12-12 | 2018-12-12 | A kind of input over under-voltage protection circuit and appliances power source |
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| CN (1) | CN209488160U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112736858A (en) * | 2020-12-31 | 2021-04-30 | 杭州拓深科技有限公司 | Alternating-current overvoltage self-turn-off protection system and protection method |
-
2018
- 2018-12-12 CN CN201822089843.XU patent/CN209488160U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112736858A (en) * | 2020-12-31 | 2021-04-30 | 杭州拓深科技有限公司 | Alternating-current overvoltage self-turn-off protection system and protection method |
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