CN107770913A - A kind of protection circuit for preventing metal-oxide-semiconductor from overloading - Google Patents
A kind of protection circuit for preventing metal-oxide-semiconductor from overloading Download PDFInfo
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- CN107770913A CN107770913A CN201711067439.6A CN201711067439A CN107770913A CN 107770913 A CN107770913 A CN 107770913A CN 201711067439 A CN201711067439 A CN 201711067439A CN 107770913 A CN107770913 A CN 107770913A
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection
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Abstract
Present disclose provides a kind of protection circuit for preventing metal-oxide-semiconductor from overloading, its first input end is used to input first voltage, and the second input is used for input reference voltage；It is the very first time that first voltage is changed into the time required to reference voltage value from zero, and protection circuit has default ON time, presets the first multiple that ON time is the very first time；First voltage was the second time the time required to being changed into crest voltage from zero, second time was the second multiple of the very first time, and when the second multiple is less than the first multiple, output end is overturn after the second time, when the second multiple is more than the first multiple, output end is overturn after default ON time.
Description
Technical field
A kind of this disclosure relates to integrated circuit fields, and in particular to protection circuit for preventing metal-oxide-semiconductor from overloading.
Background technology
In the last few years, Switching Power Supply had obtained more and more extensive application, and the application of LED drive power therein is even more
Great popularization is arrived.Power MOS has a wide range of applications in field of power supplies, so that LED drives as an example, in LED drivings, and peak value
Current control mode realizes that the method for constant current output is widely adopted, and its circuit theory diagrams is as shown in figure 1, be prior art
The typical application circuit of BUCK circuits.The circuit includes the rectifier bridge, input capacitance Cin, load being made up of diode D1~D4
Control in LED lamp bead, fictitious load R1, output capacitance Cout, inductance L, sustained diode 5, sampling resistor Rcs and dotted line frame
Device processed, power MOS Q1 are integrated in controller；The hv termination inductance of controller, voltage sample termination sampling resistor Rcs, vcc
Terminate Cvcc.
Above-mentioned circuit theory：After power switch pipe Q1 is opened, ignore the conduction voltage drop of power switch pipe and Rcs pressure
Drop, the voltage at inductance L both ends is input voltage vin and output voltage Vout difference Vin-Vout, and this will make it that inductance is electric
Stream linearly becomes big with slope (Vin-Vout)/L, and the electric current flows through sampling resistor Rcs so that Vcs voltages become larger, and work as Vcs
When voltage reaches internal reference voltage Vref, comparator CMP1 output control rest-set flip-flop switch-off power pipes；Power tube turns off it
Afterwards, because inductive current can not be mutated so that sustained diode 5 turns on, and inductance both end voltage is about Vout, inductive current with
Slope Vout/L is gradually reduced, and when inductive current is reduced to 0, inductance demagnetization terminates, at this moment the demagnetization detection inside controller
Module control rest-set flip-flop reopens power tube, a complete complete switch periods.
In circuit shown in Fig. 1, in order to which the electric current for preventing from flowing through metal-oxide-semiconductor and inductance is excessive, setting has overcurrent protection ratio
Compared with device, the effect of the comparator is exactly the cut-off signals of the output mos when sampled voltage Vcs is more than internal Vref, is turned off
MOS, so as to avoid MOS electric currents excessive.The peak value for flowing through power MOS is Ipk=Vref/Rcs, if sampling resistor Rcs electricity
Resistance very little, may result in that peak point current Ipk is very big, if metal-oxide-semiconductor Q1 saturation tube voltage drop is Vdsat, the conducting resistance of linear zone
Resist for Rdson, if Ipk*Rdson ＞ Vdsat, then power MOS pipe Q1 can enter saturation region.
After metal-oxide-semiconductor enters saturation region, the drain-source voltage meeting rapid increase of metal-oxide-semiconductor, this may result in electric during Ton
Feeling the pressure drop at L both ends reduces, and causes ON time to become the big maximum ON time Tonmax for even reaching inner setting；Conducting
The big when anaplasia that power MOS can be caused to be in saturation region again of change of time is big, causes MOS power consumption to steeply rise, ultimately results in
MOS burns, system aircraft bombing.
Disclosure
(1) technical problems to be solved
Present disclose provides a kind of protection circuit for preventing metal-oxide-semiconductor from overloading, power MOS pipe can be controlled timely in saturation region
Shut-off, avoid metal-oxide-semiconductor from burning and system aircraft bombing, increase the reliability of system.
(2) technical scheme
Present disclose provides a kind of protection circuit for preventing metal-oxide-semiconductor from overloading, including：First input end, the second input and
Output end, the first input end are used to input first voltage, and second input is used for input reference voltage；Described first
It is the very first time that voltage is changed into the time required to reference voltage value from zero, and the protection circuit has default ON time, described pre-
If ON time is the first multiple of the very first time；It is second that the first voltage is changed into the time required to crest voltage from zero
Time, second time is the second multiple of the very first time, when the second multiple is less than the first multiple, during by second
Between after output end upset, when the second multiple is more than the first multiple, the output end is overturn after default ON time.
In some embodiments of the present disclosure, in addition to：Comparator, first switch, second switch, third switch, the 4th
Switch, the 5th switch, the 6th switch, the first electric capacity, the second electric capacity, the 3rd electric capacity, operational amplifier and current source；The comparison
The in-phase input end of device is first input end and connects the source electrode of metal-oxide-semiconductor, and as the second input, it is exported its reverse input end
Hold the break-make of controlling switch；The homophase input termination current source of the operational amplifier, the first end of second electric capacity, second
The first end of switch, its reverse input end connect the first end of the 3rd electric capacity, the first end of the 3rd switch, the first of the 4th switch
End, it exports the second end of the switch of termination the 4th, the first end of the 5th switch；First switch first terminates the second of second switch
End and the first end of the first electric capacity；The end of first switch second, first the second end of electric capacity, second the second end of electric capacity, the 3rd electric capacity
Two ends, the 3rd the second end of switch, the 6th the second end of switch ground connection；The first end of second termination of the 5th switch, and as protection
The output end of circuit, output overloading protection signal.
In some embodiments of the present disclosure, first electric capacity, the second electric capacity, the ratio between the capacitance of the 3rd electric capacity are
(K-2): 1: 1, first multiple is K.
In some embodiments of the present disclosure, M times of voltage on the basis of the crest voltage, the second multiple is M.
In some embodiments of the present disclosure, when not reaching after metal-oxide-semiconductor conducting and the very first time, the output end of comparator is defeated
Go out 0, first switch, the 4th switch, the 6th switch conduction, second switch, the 3rd switch, the 5th cut-off out, and current source is to second
Electric capacity is charged, and the 3rd electric capacity is also electrically charged, and overload protection signal is 0.
In some embodiments of the present disclosure, when reaching the very first time, the output end output signal 1 of comparator, second
Switch, the 5th switch conduction, first switch, the 3rd switch, the 4th switch, the 6th switch off.
In some embodiments of the present disclosure, after the second time or default ON time, first switch, second open
Close, the 3rd switch, the 4th switch, the 6th switch conduction, the 5th switches off, and overload protection signal is 1.
The disclosure additionally provides a kind of controller, including：Above-mentioned protection circuit, metal-oxide-semiconductor, rest-set flip-flop, drive circuit and
Move back magnetic sensor circuit；The source electrode of metal-oxide-semiconductor connects the in-phase input end of comparator；The output end of the S termination protection circuits of rest-set flip-flop,
Its Q end connects the grid of metal-oxide-semiconductor through drive circuit, and its R end connects the grid of metal-oxide-semiconductor through moving back magnetic sensor circuit.
The disclosure additionally provides a kind of LED protection circuit, including：Controller noted above, rectifier bridge, input capacitance, fictitious load,
Output capacitance, inductance, fly-wheel diode, sampling resistor.
In some embodiments of the present disclosure, rectifier bridge generation input voltage；Input capacitance first terminates input voltage, the
Two ends are grounded；The negative pole of fly-wheel diode connects input voltage, and positive pole connects the first end of inductance；Output capacitance, fictitious load are parallel to
Second end of input voltage and inductance, the second end ground connection of sampling resistor.
(3) beneficial effect
It can be seen from the above technical proposal that the disclosure can with the working condition of dynamic detection metal-oxide-semiconductor, when metal-oxide-semiconductor due to
Electric current is excessive to enter saturation region, the big peakvalue's checking that have impact on inside of change of the drain-source voltage of metal-oxide-semiconductor so that needed for peakvalue's checking
When long the time required to when time is than normal work, MOS is turned off by metal-oxide-semiconductor overload protection, avoids MOS from working long hours in saturation
Area and cause aircraft bombing.
Brief description of the drawings
Fig. 1 is the LED drive circuit figure of prior art；
Fig. 2 is the protection circuit figure for preventing metal-oxide-semiconductor overload of the embodiment of the present disclosure；
The timing waveform of protection circuit when Fig. 3 is system worked well；
Timing waveform when Fig. 4 is system trigger metal-oxide-semiconductor overload protection.
Fig. 5 applies the circuit diagram in LED drive circuit for the protection circuit of the embodiment of the present disclosure.
Embodiment
Below in conjunction with the accompanying drawing in embodiment and embodiment, the technical scheme in the embodiment of the present disclosure is carried out it is clear,
Complete description.Obviously, described embodiment is only disclosure part of the embodiment, rather than whole embodiments.Base
Embodiment in the disclosure, those of ordinary skill in the art obtained under the premise of creative work is not made it is all its
His embodiment, belong to the scope of disclosure protection.
The embodiment of the disclosure one provides a kind of protection circuit for preventing metal-oxide-semiconductor from overloading, and shown in Figure 2, it includes：Than
Compared with device CMP2, logic circuit, switch K1, K2, K3, K4, K5, K6, electric capacity C1, C2, C3, operational amplifier A 1 and current source Ic.
Wherein, comparator CMP2 output termination logic circuit, logic circuit also receive swon signals, and swon signals is most
The control signal of control metal-oxide-semiconductor switch eventually, the output end of logic circuit is K1~K6control logic buses, and it includes 6
Control signal, K1~K6 is controlled respectively.The CSH and swon of comparator CMP2 output ends output produce by the processing of logic circuit
The clock signal that controlling switch K1~K6 is switched on or off, switch available transmission door are realized.
The homophase input termination current source Ic of operational amplifier A 1, electric capacity C2 first end, K2 first end is switched, reversely
Input termination capacitor C3 first end, K3 first end, K4 first end, output termination K4 the second end, K5 first end.
Switch K1 first and terminate K2 the second end and electric capacity C1 first end；Switch K1 the second end ground connection；Electric capacity C1's
Second end is grounded；Electric capacity C2 the second end ground connection；Electric capacity C3 the second end ground connection；Switch K3 the second end ground connection；Switch K5's
Second termination K6 first end；Switch K6 the second end ground connection.
The protection circuit of the present embodiment is the part of controller.Controller also includes：Metal-oxide-semiconductor Q1, rest-set flip-flop, drive
Dynamic circuit DRV, comparator CMP1, move back magnetic sensor circuit Tdem_det.Protection circuit is used to prevent metal-oxide-semiconductor Q1 from overloading.Protection electricity
Road comparator CMP2 in-phase input end connection metal-oxide-semiconductor Q1 source electrode, the voltage sampling port cs as controller；Comparator CMP2
Reverse input end meet reference voltage V ref1；Letter is protected as the output end output overloading of protection circuit in the second end for switching K5
Number OLP, protection circuit output end and comparator CMP1 output end access OR gate (OR) circuit, OR circuit output end connection RS
The S ends of trigger；The Q ends of rest-set flip-flop connect metal-oxide-semiconductor Q1 grid through drive circuit DRV, and its R end is through moving back magnetic sensor circuit
Tdem_det connects metal-oxide-semiconductor Q1 grid, and the voltage sampling port cs of metal-oxide-semiconductor Q1 source electrode as controller, it drains as control
The high voltage supply end (hv ends) of device.
Part of the controller as LED protection circuit, referring to Fig. 5, LED protection circuit also includes：Rectifier bridge, input
Electric capacity Cin, load LED lamp pearl, fictitious load R1, output capacitance Cout, inductance L, sustained diode 5, sampling resistor Rcs.
The hv termination inductance L of controller first end, its voltage sample termination sampling resistor Rcs first ends, power end
(vcc ends) connects electric capacity Cvcc first ends.Rectifier bridge includes four diodes D1, D2, D3, D4, and it is converted to alternating voltage Ac
DC input voitage Vin.Input capacitance Cin first terminates input voltage vin, the second end ground connection.The negative pole of sustained diode 5
Input voltage vin is connect, positive pole connects inductance L first end.Output capacitance Cout, fictitious load R1, load LED lamp pearl are parallel to input
Voltage Vin and inductance L the second end, load LED lamp pearl both ends output voltage Vout.Sampling resistor Rcs the second end and electric capacity
Cvcc the second end ground connection.
The present embodiment prevents the protection circuit that metal-oxide-semiconductor overloads, after metal-oxide-semiconductor Q1 conductings, voltage sampling port cs voltage Vcs
Become since 0 big.Before voltage Vcs reaches reference voltage V ref1, comparator CMP2 output signal CSH is 0, now K1
Conducting, K2 disconnect, and K3 disconnects, and K4 conductings, K5 disconnects, K6 conductings.Current source Ic charges to electric capacity C2, while operational amplifier A 1
Follower is served as, electric capacity C3 is also electrically charged, its voltage follow electric capacity C2 voltage, and output overloading protection signal OLP is 0.
As arrival time t1, voltage Vcs reaches reference voltage V ref1, and comparator CMP2 output signal CSH upsets are 1,
Now, K2 is first turned on, is then turned off K1, K3 disconnects, and K4 disconnects, and K5 conductings, K6 disconnects.
At the t1 moment, the in-phase input end A of operational amplifier A 1, inverting input B voltage are all ic*t1/c2, icFor
Current source Ic current value, c2For electric capacity C2 capacitance.Operational amplifier A 1 serves as comparator, and the voltage on electric capacity C3 is kept
Constant, electric capacity C1 is in parallel with C2, and the voltage of the two zero setting again, current source Ic charges to shunt capacitance C1 and C2.
After ON time t2, metal-oxide-semiconductor is turned off, and now K1 is turned on, K2 conductings, K3 conductings, K4 conductings, K5 disconnections, K6
Conducting, all capacitance states are all reset.
In the present embodiment, the ratio between electric capacity C1, C2, C3 capacitance c1∶c2∶c3=(K-2): 1: 1, this allows for comparator
The front and rear electric capacity C2 of output signal CMP upsets voltage rate of rise ratio is (K-1): 1, the ON time of such words metal-oxide-semiconductor
(i.e. the time that the output signal OLP of operational amplifier A 1 is 1 from 0 upset) t2=t1+ (K-1) * t1=K*t1.
The reference voltage V ref1 of the present embodiment protection circuit value can set it is smaller, thus can be approx
Think before voltage Vcs reaches Vref1, metal-oxide-semiconductor is operated in linear zone.Meanwhile the voltage sample of initialization system normal work
Cs crest voltage Vref=M*Vref1 is held, and there are M ＜ K.When controller and LED protection circuit normal work, metal-oxide-semiconductor begins
Linear zone is operated in eventually, now voltage Vcs reaches the ON time t3=M*t1 required for crest voltage Vref, due to M ＜ K,
So t3 ＜ t2, therefore limited under normal operation by the crest voltage inside controller to turn off metal-oxide-semiconductor, i.e. metal-oxide-semiconductor
Turned off after ON time t3, MOS overload protections can't be triggered.If corresponding state is 1 during switch conduction, during shut-off
Corresponding state is 0, then during normal work, the timing diagram of protection circuit is as shown in Figure 3.
If sampling resistor Rcs resistance value very little, and peak point current Ipk, metal-oxide-semiconductor Q1 saturation pipe pressure Vdsat and
The conduction impedance Rdson of linear zone meets Ipk*Rdson ＞ Vdsat, then during metal-oxide-semiconductor turns on, metal-oxide-semiconductor can enter saturation
Area, its drain-source both end voltage Vds can become big rapidly, due to falling the voltage difference V at inductance L both endsL=Vin-Vout-Vds, VLMeeting
Rapid to decline, this results in inductance L electric current rate of rise K1=VL/ L diminishes, so that sampling resistor Rcs voltage Vcs's is upper
Rise slope to taper into, this this may result in voltage Vcs and reaches ON time required for the crest voltage Vref of normal work
T3 becomes big, so that t3 ＞ t2.Now metal-oxide-semiconductor turns off after ON time t2 rather than t3, is protected so as to trigger overload
Shield, metal-oxide-semiconductor turned off before the generation of normal turn-off signal, avoid due to metal-oxide-semiconductor work long hours it is fast in saturation region, power consumption
Speed rises the danger so as to aircraft bombing.As shown in figure 4, when voltage Vcs is also not reaching to Vref, operational amplifier A 1 it is same mutually defeated
Enter to hold A voltage reach again operational amplifier A 1 inverting input B sampling keep voltage, comparator CMP2 output signals
OLP upsets are 1, and controller controls shut-off metal-oxide-semiconductor according to OLP upset, plays a part of MOS overload protections.
Another embodiment of the disclosure also provides a kind of controller, and controller includes：The protection circuit of above-described embodiment, MOS
Pipe Q1, rest-set flip-flop, drive circuit DRV and magnetic sensor circuit Tdem_det is moved back, protection circuit is used to prevent metal-oxide-semiconductor Q1 from overloading.
Another embodiment of the disclosure also provides a kind of LED protection circuit, and LED protection circuit includes：The control of above-described embodiment
Device processed, rectifier bridge, input capacitance Cin, load LED lamp pearl, fictitious load R1, output capacitance Cout, inductance L, sustained diode 5,
Sampling resistor Rcs.
So far, the present embodiment is described in detail combined accompanying drawing.According to above description, those skilled in the art
There should be clear understanding to the disclosure.
It should be noted that in accompanying drawing or specification text, the implementation that does not illustrate or describe is affiliated technology
Form known to a person of ordinary skill in the art, is not described in detail in field.In addition, above-mentioned definition to each element and not only limiting
Various concrete structures, shape or the mode mentioned in embodiment, those of ordinary skill in the art can be carried out simply more to it
Change or replace, such as：
(1) direction term mentioned in embodiment, such as " on ", " under ", "front", "rear", "left", "right" etc., only it is ginseng
The direction of accompanying drawing is examined, is not used for limiting the protection domain of the disclosure；
(2) consideration that above-described embodiment can be based on design and reliability, the collocation that is mixed with each other uses or and other embodiment
Mix and match uses, i.e., the technical characteristic in different embodiments can freely form more embodiments.
Particular embodiments described above, the purpose, technical scheme and beneficial effect of the disclosure are carried out further in detail
Describe in detail bright, should be understood that the specific embodiment that the foregoing is only the disclosure, be not limited to the disclosure, it is all
Within the spirit and principle of the disclosure, any modification, equivalent substitution and improvements done etc., the guarantor of the disclosure should be included in
Within the scope of shield.
Claims (10)
1. a kind of protection circuit for preventing metal-oxide-semiconductor from overloading, including：First input end, the second input and output end,
The first input end is used to input first voltage, and second input is used for input reference voltage；
It is the very first time that the first voltage is changed into the time required to reference voltage value from zero, and the protection circuit has default conducting
Time, the default ON time are the first multiple of the very first time；The first voltage is changed into crest voltage institute from zero
It is the second multiple of the very first time to take time as the second time, second time,
When the second multiple is less than the first multiple, the output end upset after the second time, when the second multiple is more than first
During multiple, the output end upset after default ON time.
2. protection circuit as claimed in claim 1, in addition to：Comparator, first switch, second switch, third switch, the 4th
Switch, the 5th switch, the 6th switch, the first electric capacity, the second electric capacity, the 3rd electric capacity, operational amplifier and current source；
The in-phase input end of the comparator is first input end and connects the source electrode of metal-oxide-semiconductor, and its reverse input end is as second
Input, the break-make of its output end controlling switch；
The homophase input termination current source of the operational amplifier, the first end of second electric capacity, the first end of second switch,
Its reverse input end connects the first end of the 3rd electric capacity, the first end of the 3rd switch, the first end of the 4th switch, and it exports termination the
Second end of four switches, the first end of the 5th switch；
First switch first terminates the second end of second switch and the first end of the first electric capacity；The end of first switch second, the first electricity
Hold the second end, second the second end of electric capacity, the 3rd the second end of electric capacity, the 3rd the second end of switch, the 6th the second end of switch ground connection；5th
The first end of second termination of switch, and as the output end of protection circuit, output overloading protection signal.
3. protection circuit as claimed in claim 2, first electric capacity, the second electric capacity, the ratio between the capacitance of the 3rd electric capacity are
(K-2): 1: 1, first multiple is K.
4. protection circuit as claimed in claim 2, M times of voltage on the basis of the crest voltage, the second multiple is M.
5. protection circuit as claimed in claim 2, when not reaching after metal-oxide-semiconductor conducting and the very first time, the output end of comparator
Output 0, first switch, the 4th switch, the 6th switch conduction, second switch, the 3rd switch, the 5th cut-off out, current source is to the
Two electric capacity are charged, and the 3rd electric capacity is also electrically charged, and overload protection signal is 0.
6. protection circuit as claimed in claim 5, when reaching the very first time, the output end output signal 1 of comparator, second
Switch, the 5th switch conduction, first switch, the 3rd switch, the 4th switch, the 6th switch off.
7. protection circuit as claimed in claim 6, after the second time or default ON time, first switch, second open
Close, the 3rd switch, the 4th switch, the 6th switch conduction, the 5th switches off, and overload protection signal is 1.
8. a kind of controller, including：Protection circuit, metal-oxide-semiconductor as any one of claim 1 to 7, rest-set flip-flop, drive
Move circuit and move back magnetic sensor circuit；
The source electrode of metal-oxide-semiconductor connects the in-phase input end of comparator；
The output end of the S termination protection circuits of rest-set flip-flop, its Q end connect the grid of metal-oxide-semiconductor through drive circuit, and its R end is through demagnetization
Detection circuit connects the grid of metal-oxide-semiconductor.
9. a kind of LED protection circuit, including：Controller, rectifier bridge described in claim 8, input capacitance, fictitious load, output
Electric capacity, inductance, fly-wheel diode, sampling resistor.
10. LED protection circuit as claimed in claim 1, rectifier bridge generation input voltage；The termination input electricity of input capacitance first
Pressure, the second end ground connection；The negative pole of fly-wheel diode connects input voltage, and positive pole connects the first end of inductance；Output capacitance, fictitious load are simultaneously
It is coupled to the second end of input voltage and inductance, the second end ground connection of sampling resistor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711067439.6A CN107770913B (en) | 2017-11-02 | 2017-11-02 | Protection circuit for preventing MOS tube from overloading |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711067439.6A CN107770913B (en) | 2017-11-02 | 2017-11-02 | Protection circuit for preventing MOS tube from overloading |
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| CN107770913A true CN107770913A (en) | 2018-03-06 |
| CN107770913B CN107770913B (en) | 2020-03-17 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110611983A (en) * | 2019-09-03 | 2019-12-24 | 英特曼电工（常州）有限公司 | Single-live-wire multifunctional dimmer |
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| CN106300275A (en) * | 2016-09-26 | 2017-01-04 | 辉芒微电子（深圳）有限公司 | A kind of BUCK drive circuit, power supply chip and application thereof |
| CN206195635U (en) * | 2016-10-10 | 2017-05-24 | 上海晶丰明源半导体股份有限公司 | Controller and adopt switching power supply of this controller |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110611983A (en) * | 2019-09-03 | 2019-12-24 | 英特曼电工（常州）有限公司 | Single-live-wire multifunctional dimmer |
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