CN107508255B - A kind of power signal source Drive Protecting Circuit - Google Patents
A kind of power signal source Drive Protecting Circuit Download PDFInfo
- Publication number
- CN107508255B CN107508255B CN201710776153.9A CN201710776153A CN107508255B CN 107508255 B CN107508255 B CN 107508255B CN 201710776153 A CN201710776153 A CN 201710776153A CN 107508255 B CN107508255 B CN 107508255B
- Authority
- CN
- China
- Prior art keywords
- unit
- signal
- voltage
- driving
- triode
- 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
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/20—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/08—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current
- H02H3/10—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess current additionally responsive to some other abnormal electrical conditions
Landscapes
- Amplifiers (AREA)
- Testing Of Individual Semiconductor Devices (AREA)
Abstract
A kind of power signal source Drive Protecting Circuit, including power supply unit, signal synthesis unit, overrun testing unit, driving unit, feedback unit and isolation boosting output unit；Said supply unit is used to extraneous high-voltage DC power supply being converted into low-voltage dc power supply, and the low-voltage dc power supply controls on-off by optical coupling unit；The signal synthesis unit by extraneous input signal and feedback signal for being synthesized and controlling the bipolar power supply of transport and placing device, signal of the transport and placing device bipolar power supply for the positive-negative half-cycle of driving power signal source, the output information of the transport and placing device is sent to overrun testing unit simultaneously, and whether the overrun testing unit is transfinited the optical coupling unit controlled in power supply unit by detecting signal；The isolation boosting output unit is used to boost to the power signal source that driving unit is sent the power signal of the higher voltage of secondary side.
Description
Technical field
The present invention relates to a kind of power signal source Drive Protecting Circuits.
Background technique
It in general hardware driving circuit, requires that there is protection circuit, and protects and be divided into hardware protection and software guarantor
Shield.So-called software protection generally refer to by output end measurement, calculating and analysis, according to the problem of analyzing to original
The advantages of beginning signal carries out respective handling (such as shutdown signal) etc. to realize, software protection be can analyze it is thinner, very
What more hardware can not react can particularly point out (such as THD) in software protection, but the disadvantage of software protection is exactly to ring
It answers speed slow, belongs to post-processing, protect evening after hardware has damaged sometimes again, therefore protecting effect is limited.
And hardware protection it is general there are many kinds of, have output end protected, have and front end protected.Since driving exports
End has the features such as voltage is high, and power is big, therefore is the most weak place of entire circuit link, and most faults are equal
Occur herein.Though power amplifier output end is most easily broken down, " treating the head when the head aches, foot pain doctor foot " can not reach pre- sometimes
The effect of phase.
Summary of the invention
In order to overcome the deficiencies of the prior art, the present invention provides a kind of power signal source Drive Protecting Circuit.
Technical solution provided by the invention are as follows:
It is defeated including power supply unit, signal synthesis unit, overrun testing unit, driving unit, feedback unit and isolation boosting
Unit out；
Said supply unit is used to extraneous high AC voltage being rectified into high direct voltage voltage source and be depressured as low pressure
DC voltage source, the low-voltage DC potential source control on-off by optical coupling unit；The low-voltage DC potential source is for controlling
The control triode of the driving unit；
The signal synthesis unit is used to synthesize extraneous input signal and feedback signal and control the double of transport and placing device
Polarity power, the bipolar power supply of the transport and placing device by driving unit with the signal of the positive-negative half-cycle of driving power signal source,
The output information of the transport and placing device is sent to overrun testing unit simultaneously, and whether the overrun testing unit is transfinited by detection number
Control the optical coupling unit in power supply unit；
The driving unit is used to the composite signal of transport and placing device being driven to high-power signal source, and the driving unit includes
Control triode (Q1 and Q2), overload protection triode (Q3 and Q4) and driving metal-oxide-semiconductor (Q5 and Q6)；The control triode
Base stage controls on-off by the optical coupling unit in said supply unit, and controls driving MOS according to the sampling voltage of divider resistance
The grid of pipe, the control transistor emitter are used to control the power supply and output signal of signal synthesis unit transport and placing device, current collection
Pole is supplied to the signal source of driving unit；The overload protection triode and corresponding resistor constitute the overload of driving metal-oxide-semiconductor together
Circuit is protected, driving metal-oxide-semiconductor is used for weak signal power amplification and exports to isolation boosting output unit.
The feedback unit is used to detect the sampled signal of the secondary side of the isolation boosting output unit, and sampling is believed
Number it is sent to the signal synthesis unit；
The isolation boosting output unit is used to the power signal source that driving unit is sent boosting to the higher of secondary side
The power signal of voltage.
Preferably, said supply unit, signal synthesis unit, driving unit and feedback unit are using the double electricity of Symmetrical
Source design.
Preferably, high direct voltage voltage source is passed through sata power resistance, zener diode and filter by said supply unit
Wave capacitor is converted to low-voltage DC potential source, and the low-voltage DC potential source controls on-off, the optocoupler by optical coupling unit
Unit is closed to be controlled by the optical coupling unit in overrun testing unit.
Preferably, the control information of the optical coupling control unit include output transfinite protection, temperature over-range protection and
The control point of software protection.
Preferably, the positive ends of the driving unit control triode by NPN type, positive-negative-positive overload protection triode,
P-channel drives metal-oxide-semiconductor, and sample resistance and current-limiting resistance are constituted；It is then overloaded by positive-negative-positive control triode, NPN type at negative polarity end
Triode, N-channel is protected to drive metal-oxide-semiconductor, sample resistance and current-limiting resistance are constituted；
The base stage of the control triode is controlled by optical coupling unit, emitting stage and the signal synthesis unit transport and placing device
Power supply is connected；Positive and negative terminal (± 170V) and sample resistance, the emitter of overload protection triode, the current-limiting resistance phase of high voltage power supply
Even；High voltage power supply is connected by sample resistance with the collector for controlling triode simultaneously, and passes through current-limiting resistance and overload protection
The base resistance of triode is connected, high voltage power supply divided by sample resistance after also with the pole G and overload protection three that drive metal-oxide-semiconductor
The collector of pole pipe is connected；
The pole S of the driving metal-oxide-semiconductor is connected by current-limiting resistance with high voltage power supply, and the sampled signal of current-limiting resistance is connected
It is connected to the base resistance of overload protection triode.
Preferably, the transport and placing device of the feedback unit receives the resistance point of the secondary side of the isolation boosting output unit
Signal is pressed, the output signal of feedback unit transport and placing device is used to synthesize drive by the amplifier of signal synthesis unit with extraneous input signal
Signal needed for moving cell；
Preferably, the low-pressure direct that the high direct voltage voltage source current limliting decompression of said supply unit general ± 170V is ± 15V
Galvanic electricity potential source, and pass through the control triode that this bipolarity low-voltage DC potential source controls positive and negative terminal in driving unit respectively.
It preferably, further include overrun testing unit, the overrun testing unit is used to control the light of said supply unit
Coupling diode, when detecting overload signal, the overrun testing unit control said supply unit power-off.
Beneficial effects of the present invention:
Power signal source Drive Protecting Circuit of the invention is using the transport and placing device in signal synthesis unit as core, by transport and placing device
After the external signal of signal and input that feedback unit is detected from secondary side is synthesized, pass through signal synthesis unit
Curent change in bipolar power supply controls the I of triode to control in driving unitCE, then pass through the control of divider resistance sampled signal
System driving metal-oxide-semiconductor.Entire circuit system has multiple protective.When the output overvoltage of isolation boosting output unit, pass through feedback
Unit feeds back to signal synthesis unit, and causing the amplifier in synthesis unit to export transfinites, and overrun testing unit detects the letter that transfinites
By the power supply of amplifier in optical coupling unit cut-off signals synthesis unit after number, the driving metal-oxide-semiconductor of driving unit is simultaneously turned off；When
When the output overcurrent of isolation boosting output unit, by transformer feedback to primary side and primary side current is caused to transfinite, passed through
It send after current-limiting resistance sampling to the base stage of overload triode, thus the V of the metal-oxide-semiconductor of cutting driving at onceGSSignal, i.e. shutdown driving
Metal-oxide-semiconductor.By this double hardware protection being exceedingly fast, the high reliability and high stability of whole system can be fully ensured that.
Detailed description of the invention
Fig. 1 is the schematic block circuit diagram of power signal source Drive Protecting Circuit of the invention；
Fig. 2 be the signal synthesis unit of power signal source Drive Protecting Circuit of the invention, driving unit, feedback unit and
The circuit diagram of isolation boosting output unit；
Fig. 3 is the power supply unit of power signal source Drive Protecting Circuit of the invention and the circuit diagram of overrun testing unit.
Specific embodiment
The present invention will be further explained below with reference to the attached drawings；
A kind of power signal source Drive Protecting Circuit, as shown in Figure 1, Figure 2 and Figure 3, including the synthesis of power supply unit 1, signal
Unit 2, driving unit 3, feedback unit 4, isolation boosting output unit 5 and overrun testing unit 6；Said supply unit 1, signal
Synthesis unit 2, driving unit 3 and feedback unit 4 are designed using Symmetrical dual power supply.
As shown in figure 3, high direct voltage voltage source is passed through sata power resistance, zener diode and filter by said supply unit
Wave capacitor is converted to low-voltage DC potential source；The low-voltage DC potential source controls on-off by optical coupling unit；The low-pressure direct
Galvanic electricity potential source is used to control the control triode (i.e. Q1 and Q2) of the driving unit；The optical coupling unit is by overrun testing list
The output signal control of member；The signal of the overrun testing unit is from the output of amplifier in the signal synthesis unit.Institute
Power supply unit is stated by high voltage supply voltage ± 170V by generating after sata power resistance, zener diode and filter capacitor
The supply voltage of ± 15V, i.e. G+ and G-, G+ and G- herein are controlled by optical coupling unit U4 and U5 respectively, when U4 and U5 is connected
When, G+ and G- can become 0V.G+ and G- is respectively used to control the base stage of triode Q1 and Q2 in control driving unit, as G+ and
When G- can become 0V, the cut-off of Q1 and Q2 triode, flowing through the electric current on divider resistance R14 and R15 is 0, therefore R14 and R15
On voltage be also 0, cause Q5 and Q6 to be also switched off, output close.When U4 and U5 are closed, G+ and G- be respectively+15V and-
The power supply and output of 15V, amplifier U1 will be in normal condition, be become by the electric current of amplifier bipolar power supply in signal synthesis unit
Change, to control the I of Q1 and Q2CEElectric current, the output electricity of control driving metal-oxide-semiconductor (Q5 and Q6) after being sampled by divider resistance
Pressure.Optical coupling unit U6, U7, U8 of second optical coupling control unit respectively correspond output transfinite protection, temperature over-range protection and
Software protection, temperature over-range protection and software protection mode and the output protected mode that transfinites are identical, are all by control G+ and G-
Power supply realize.Optical coupling unit U4 and U5 are series connection, to ensure that ± 15V is simultaneously turned off or opened.Second optical coupling control
Connect after optical coupling unit U6, U7, U8 of unit processed is in parallel with U4 and U5, if such U6, U7, U8 have all the way control instruction arrive
Come, G+ and G- will be 0.The overrun testing unit 6 is used to control the optical coupling diode of said supply unit, when detecting
When overload signal, overrun testing unit control said supply unit power-off, wherein the amplifier U3A of overrun testing unit and
U3B derives from the signal of signal synthesis unit transport and placing device for controlling U6, the input signal of U3A.
The main component of the signal synthesis unit is transport and placing device U1, is detected feedback unit from secondary side by transport and placing device
Signal FB+ and input external signal IN_SIG synthesized after, by the bipolar power supply of signal synthesis unit
Curent change controls the I of triode to control in driving unitCE, then pass through divider resistance sampled signal control driving metal-oxide-semiconductor.It is defeated
When normal out, protection circuit does not work, and the nominal voltage of at this moment T1 grade of transformer output is that 380V (is lifted here with 380V
Example).
When isolating transformer output earth short circuit, since immediate current is very big, primary side is fed back to by transformer T1
Electric current is also very big, so that protecting circuit to permit more than the overload current centered on Q3 and Q4 by the electric current moment in Q5 and Q6
Perhaps threshold value, therefore moment Q5 and Q6 is at off state；Simultaneously after secondary terminal shortcircuit, secondary end passes through electric resistance partial pressure
(or mutual inductor sampling current) resulting negative-feedback signal FB+ moment becomes 0, and the negative terminal of U1 is fed back to by amplifier U2, so that
The output signal SIG_WARN moment of U1 is more than the signal of 6V or so, and SIG_WARN signal is led by amplifier U3A and U3B output
Light passing coupling U6, so that G+ and G- are closed, while Q1 and Q2 cut-off, amplifier U2 short of electricity, and because Q1 and Q2 ends, metal-oxide-semiconductor Q5 and Q6
VGSSignal is 0, Q5 and Q6 is also at off state, to realize the hardware protection process of entire driving circuit.
Likewise, isolating transformer secondary side output at this time existed when isolating transformer output occurs across mutually short circuit
Situation is pressed, signal synthesis unit is fed back to by feedback unit, causing the amplifier in synthesis unit to export transfinites, overrun testing list
Member detects to transfinite after signal through the power supply of amplifier in optical coupling unit cut-off signals synthesis unit, simultaneously turns off driving unit
Driving metal-oxide-semiconductor；In addition it when across mutually short-circuit over-voltage, generally synchronizes and overcurrent occurs, by transformer feedback to primary side and lead
It causes primary side current to transfinite, is sent after being sampled by current-limiting resistance to the base stage of overload triode, thus the metal-oxide-semiconductor of cutting driving at once
VGSSignal, i.e. shutdown driving metal-oxide-semiconductor.
It is transfinited by overload protection and over-voltage and protects this double hardware protection being exceedingly fast, can fully ensure that the height of whole system
Reliability and high stability.
Claims (8)
1. a kind of power signal source Drive Protecting Circuit, it is characterised in that:
It is exported including power supply unit, signal synthesis unit, overrun testing unit, driving unit, feedback unit and isolation boosting single
Member；
Said supply unit is used to extraneous high AC voltage being rectified into high direct voltage voltage source and be depressured as low-voltage direct
Voltage source, the low-voltage DC potential source control on-off by optical coupling unit；The low-voltage DC potential source is described for controlling
The control triode of driving unit；
Extraneous input signal and feedback signal for being synthesized and being controlled signal conjunction by the transport and placing device of the signal synthesis unit
At the bipolar power supply of unit transport and placing device, the bipolar power supply of the transport and placing device is by driving unit with driving power signal source
The signal of positive-negative half-cycle, while the output information signal of the transport and placing device is sent to overrun testing unit, the overrun testing list
Member is by detecting whether output information signal transfinites the optical coupling unit controlled in power supply unit；
The driving unit is used to for the composite signal of transport and placing device being driven to high-power signal source, and the driving unit includes control
Triode, overload protection triode and driving metal-oxide-semiconductor；The base stage of the control triode is by the optical coupling in said supply unit
Unit controls on-off, and the grid of driving metal-oxide-semiconductor, the control transistor emitter are controlled according to the sampling voltage of divider resistance
For controlling the power supply and output signal of signal synthesis unit transport and placing device, collector is supplied to the signal source of driving unit；It is described
Overload protection triode, current-limiting resistance constitute the overload protecting circuit of driving metal-oxide-semiconductor together, and driving metal-oxide-semiconductor is used for weak signal
Power amplification is simultaneously exported to isolation boosting output unit；
The feedback unit is used to detect the sampled signal of the secondary side of the isolation boosting output unit, and sampled signal is sent out
Give the signal synthesis unit；
The isolation boosting output unit is used to boost to power signal source the power signal of secondary side voltage.
2. power signal source Drive Protecting Circuit according to claim 1, it is characterised in that:
Said supply unit, signal synthesis unit, driving unit and feedback unit are designed using Symmetrical bipolar power supply.
3. power signal source Drive Protecting Circuit according to claim 1, it is characterised in that:
The high direct voltage voltage source of said supply unit general ± 170V passes through sata power resistance, zener diode and capacitor filtering
The low-voltage DC potential source of ± 15V is converted to, it is ± 15V that low-voltage DC potential source, which controls its normal output by optical coupling unit,
Or output is 0, the optical coupling unit is controlled by the second optical coupling unit.
4. power signal source Drive Protecting Circuit according to claim 3, it is characterised in that:
The control information of second optical coupling unit includes exporting the control of protection of transfiniting, temperature over-range protection and software protection
Point.
5. power signal source Drive Protecting Circuit according to claim 1, it is characterised in that:
The positive ends of the driving unit control triode, positive-negative-positive overload protection triode by NPN type, and P-channel drives MOS
Pipe, sample resistance and current-limiting resistance are constituted；Negative polarity end then controls triode, NPN type overload protection triode, N by positive-negative-positive
Channel drives metal-oxide-semiconductor, and sample resistance and current-limiting resistance are constituted；
Since positive-negative polarity end is full symmetric, principle is identical；
The base stage of the control triode is controlled by optical coupling unit, the power supply of emitter and the signal synthesis unit transport and placing device
It is connected；Positive and negative terminal ± the 170V of high direct voltage voltage source and sample resistance, the emitter of overload protection triode, current-limiting resistance phase
Even；High direct voltage voltage source is connected by sample resistance with the collector for controlling triode simultaneously, and passes through current-limiting resistance and mistake
Carry protection triode base stage be connected, high direct voltage voltage source by sample resistance divide after also with drive metal-oxide-semiconductor the pole G and mistake
The collector for carrying protection triode is connected；
The pole S of the driving metal-oxide-semiconductor is connected by current-limiting resistance with high direct voltage voltage source, and by the sampled signal of current-limiting resistance
It is connected to the base stage of overload protection triode.
6. power signal source Drive Protecting Circuit according to claim 1, it is characterised in that:
The transport and placing device of the feedback unit receives the electric resistance partial pressure signal of the secondary side of the isolation boosting output unit, feedback
The output signal of the transport and placing device of member with extraneous input signal by signal synthesis unit transport and placing device for being synthesized needed for driving unit
Signal.
7. power signal source Drive Protecting Circuit according to claim 5, it is characterised in that:
The high direct voltage voltage source current limliting decompression of said supply unit general ± 170V is the low-voltage DC potential source of ± 15V, and leads to
Cross the control triode that this bipolarity low-voltage DC potential source controls positive-negative polarity end in driving unit respectively.
8. power signal source Drive Protecting Circuit according to claim 1, it is characterised in that:
The overrun testing unit is used to control the optical coupling diode of said supply unit, when detecting overload signal, institute
State the control said supply unit power-off of overrun testing unit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710776153.9A CN107508255B (en) | 2017-08-31 | 2017-08-31 | A kind of power signal source Drive Protecting Circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710776153.9A CN107508255B (en) | 2017-08-31 | 2017-08-31 | A kind of power signal source Drive Protecting Circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107508255A CN107508255A (en) | 2017-12-22 |
| CN107508255B true CN107508255B (en) | 2019-05-07 |
Family
ID=60693502
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710776153.9A Active CN107508255B (en) | 2017-08-31 | 2017-08-31 | A kind of power signal source Drive Protecting Circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107508255B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111176357B (en) * | 2020-01-19 | 2021-07-09 | 中国科学技术大学 | Bipolar high-voltage rapid steady-state output control system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201063533Y (en) * | 2007-05-30 | 2008-05-21 | 深圳市麦格米特电气技术有限公司 | Overcurrent self-locking bridge type driving circuit |
| CN203608076U (en) * | 2013-10-28 | 2014-05-21 | 北京京铁信达铁路设备有限公司 | A high voltage IGVT driving and protection circuit |
| JP2016032319A (en) * | 2014-07-28 | 2016-03-07 | ローム株式会社 | Switching power supply device |
| CN106686798A (en) * | 2011-11-04 | 2017-05-17 | 熥昱国际电子私人有限公司 | System and device for driving a plurality of high powered led units |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10199818B2 (en) * | 2015-04-03 | 2019-02-05 | Integrated Device Technology, Inc. | System and method for wireless power transfer using over-voltage protection |
-
2017
- 2017-08-31 CN CN201710776153.9A patent/CN107508255B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201063533Y (en) * | 2007-05-30 | 2008-05-21 | 深圳市麦格米特电气技术有限公司 | Overcurrent self-locking bridge type driving circuit |
| CN106686798A (en) * | 2011-11-04 | 2017-05-17 | 熥昱国际电子私人有限公司 | System and device for driving a plurality of high powered led units |
| CN203608076U (en) * | 2013-10-28 | 2014-05-21 | 北京京铁信达铁路设备有限公司 | A high voltage IGVT driving and protection circuit |
| JP2016032319A (en) * | 2014-07-28 | 2016-03-07 | ローム株式会社 | Switching power supply device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107508255A (en) | 2017-12-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201846067U (en) | Circuit for real time monitoring and carefully protecting power supply | |
| CN206321697U (en) | A kind of over-voltage detection circuit and switching power circuit | |
| CN108206517A (en) | A kind of low cost inputs anti-overvoltage crowbar | |
| CN103208782A (en) | Comprehensive detection and electric protection device for power frequency and variable frequency power supplies | |
| CN103855678B (en) | Overvoltage and undervoltage protection circuit of drive power source | |
| CN109873408A (en) | A kind of substation quickly isolates device and partition method with D. C. power source breakdown | |
| CN208239569U (en) | A kind of dipulse test platform | |
| CN107508255B (en) | A kind of power signal source Drive Protecting Circuit | |
| CN104391536B (en) | Train power supply device load test stand electric current stepless regulator | |
| CN208273303U (en) | A kind of 0-10V adjusting control circuit of anti-overcurrent and short circuit | |
| CN205565702U (en) | Converter IGBT short -circuit protection return circuit | |
| CN202975132U (en) | Alarming device for abnormal voltage of transformer | |
| CN202424283U (en) | Charger based on single-chip three-end TOP22X integrated chip | |
| CN106707148A (en) | Switch characteristic tester | |
| CN202522638U (en) | Grid failure intelligent identification device | |
| CN202948050U (en) | Alarm device of abnormal transformer current | |
| CN207269145U (en) | A kind of protection circuit against input over-voltage for Switching Power Supply | |
| CN205960779U (en) | P type monitoring formula switching power | |
| CN206041460U (en) | GDF 5 computer high pressure excitation control ware | |
| CN213783662U (en) | Constant voltage output dimming circuit of lamp source | |
| CN212845895U (en) | Voltage comparator module circuit in short-circuit fault warning device of ammeter | |
| CN105734854A (en) | Overvoltage and overcurrent protection system of sewing equipment | |
| CN106972766A (en) | A kind of power circuit | |
| CN208227401U (en) | Mercury lamp AC power supply system | |
| CN206258553U (en) | Relay protection outlet detecting system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |