CN103457464A - Current limiting circuit on basis of switching power supplies - Google Patents
Current limiting circuit on basis of switching power supplies Download PDFInfo
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- CN103457464A CN103457464A CN 201210173610 CN201210173610A CN103457464A CN 103457464 A CN103457464 A CN 103457464A CN 201210173610 CN201210173610 CN 201210173610 CN 201210173610 A CN201210173610 A CN 201210173610A CN 103457464 A CN103457464 A CN 103457464A
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Abstract
The invention discloses a current limiting circuit on the basis of switching power supplies. The current limiting circuit comprises a switching power supply module and a feedback control module. The switching power supply module outputs direct-current power supplies, the feedback control module is connected with the switching power supply module, transmits feedback control signals according to output currents of the switching power supplies and comprises an optical coupler control module and a current control module, the current control module is used for controlling magnitudes of the output currents, a light receiving portion of the optical coupler control module is connected into the switching power supply module, a light emitting portion of the optical coupler control module is connected into the current control module, and currents of the light emitting portion are controlled by the current control module. The current limiting circuit on the basis of the switching power supplies has the advantages that the current limiting circuit only comprises transistors, resistors, the optical coupler control module and the switching power supply module, so that the circuit is simple in structure and easy to implement while a current limiting effect is realized.
Description
Technical field
The present invention relates to current-limiting circuit, particularly relate to a kind of current-limiting circuit based on Switching Power Supply.
Background technology
Light fixture in the market is mostly the LED driving, because the light fixture that LED drives is energy-efficient, long being widely used of life-span.Because LED drive circuit requires the electric current constant current in circuit, the electric current of output rated current ± 10% interior fluctuation can work.Therefore, in LED drive circuit, current-limiting circuit is necessary, but at present most current-limiting circuit employing constant current control chip etc. are realized constant current output, need too many electric elements, circuit structure complexity.
Summary of the invention
Based on this, be necessary to adopt for current-limiting circuit the problem of too much electric elements, circuit structure complexity, the simply current-limiting circuit based on Switching Power Supply of a kind of circuit structure is provided.
A kind of current-limiting circuit based on Switching Power Supply, comprise the switch power module of exporting DC power supply, also comprises the feedback control module that is connected with switch power module and sends feedback control signal according to the output current of Switching Power Supply;
Described feedback control module comprises the optocoupler control module and for controlling the current control module of described output current size, the light accepting part of described optocoupler control module is tapped into described switch power module, and the electric current that the luminous component of described optocoupler control module accesses described current control module and luminous component is subject to the control of described current control module;
Described current control module comprises voltage stabilizing didoe, output transistor, current sense resistor and current detecting transistor; The output of the luminous component of described optocoupler control module is connected with the collector electrode of described output transistor, and the base stage of described output transistor is connected with the collector electrode of described current detecting transistor;
The collector electrode of described current detecting transistor is connected with described DC power anode, and the base stage of described current detecting transistor is connected with collector electrode;
The two ends of described current sense resistor connect respectively the emitter of described output transistor and the emitter of described current detecting transistor;
The negative pole of described voltage stabilizing didoe is connected with the collector electrode of described output transistor, anodally with the emitter of described current detecting transistor, is connected.
Therein in embodiment, the square wave output module that described switch power module comprises power transformation module, transformer T1 and controlled by described feedback control module,
Described power transformation module input ac power, output head anode are connected with described transformer T1 primary coil one end, and the square wave output of described square wave output module is connected with the other end of described transformer T1 primary coil;
Described square wave output module comprises pwm switch U1 and electrochemical capacitor C4, the drain electrode output of described pwm switch U1 is connected with the primary coil of transformer T1 as the square wave output, the source electrode input end grounding of described pwm switch U1, the control end input of described pwm switch U1 divides the voltage of control by described light accepting part, and by described electrochemical capacitor C4 ground connection;
Described square wave output module also comprises second subprime coil, diode D2 and the filter capacitor C3 with described transformer T1 primary coil coupling;
Be connected in parallel on the two ends of described second subprime coil after described diode D2 and filter capacitor C3 series connection, and what be connected with an end of second subprime coil is the anode of diode D2, the other end ground connection of second subprime coil;
Described optocoupler control module is optical coupler, and described optical coupler comprises light-emitting diode and triode, and the light accepting part of described optocoupler control module is divided into described triode, and the luminous component of described optocoupler control module is described light-emitting diode;
The positive pole of described light-emitting diode is connected with DC power anode, and negative pole is connected with the collector electrode of output transistor, and the collector electrode of described triode is connected with the negative electrode of described diode D2, and emitter is connected with the control end of described pwm switch U1.
In embodiment, the described current-limiting circuit based on Switching Power Supply also comprises divider resistance R2 therein, and described divider resistance R2 mono-end is connected with the negative pole of described light-emitting diode, and the other end is connected with the collector electrode of described output transistor.
In embodiment, described power transformation module comprises rectification module, electrochemical capacitor C1, voltage stabilizing didoe ZD1 and diode D1 therein,
Described electrochemical capacitor C1 is anodal to be connected with the output of described rectification module, minus earth;
The positive pole of described voltage stabilizing didoe ZD1 with the output of described rectification module, be connected, negative pole is connected with the negative pole of described diode D1, the positive pole of described diode D1 is connected with the drain electrode of described pwm switch U1.
In embodiment, the described current-limiting circuit based on Switching Power Supply also comprises inductance L 1 therein, and an end of described inductance L 1 is connected with the input of the luminous component of described optocoupler control module, and the other end is connected with the collector electrode of described current detecting transistor.
Therein in embodiment, contact resistance R4 between the collector electrode of described current detecting transistor and base stage, described resistance R 4 changes for the saturation voltage drop that makes described current detecting transistor.
In embodiment, the described current-limiting circuit based on Switching Power Supply also comprises divider resistance R3 therein, and described divider resistance R3 mono-end is connected with DC power anode, and the other end is connected with the base stage of described current detecting transistor.
In embodiment, the described current-limiting circuit based on Switching Power Supply also comprises electrochemical capacitor C5 and C6 therein, and described electrochemical capacitor C5 and C6 all are parallel to the DC power supply two ends.
The above-mentioned current-limiting circuit based on Switching Power Supply is controlled output current by current control module, and the luminous component by the optocoupler control module converts the output current of detection to light signal and sends to the light accepting part of the optocoupler control module in the access switch power module to divide, the light accepting part of optocoupler control module divides and converts light signal to the signal of telecommunication, send to switch power module, thereby switch power module is controlled the pressure drop of DC power supply according to the signal of telecommunication of light signal conversion, and then reach the size of current of controlling in current control module.Therefore, after setting rated current, by the optocoupler control module, switch power module can be controlled the pressure drop of DC power supply, thereby the electric current of controlling in current control module remains near the fluctuation of rated current.In the above-mentioned current-limiting circuit based on Switching Power Supply, only transistor, resistance, optocoupler control module and switch power module, consist of, therefore, when realizing current limliting, circuit simple in structure, be easy to realize.
The accompanying drawing explanation
The structural representation that Fig. 1 is the current-limiting circuit based on Switching Power Supply;
The circuit theory diagrams that Fig. 2 is the current-limiting circuit based on Switching Power Supply.
Embodiment
As shown in Figure 1, be the structural representation of Switching Power Supply current-limiting circuit.A kind of current-limiting circuit based on Switching Power Supply, comprise the switch power module 10 of exporting DC power supply, also comprises the feedback control module 20 that is connected with switch power module 10 and sends feedback control signal according to the output current of switch power module 10.
The collector electrode of current detecting transistor Q2 is connected with DC power anode, and the base stage of current detecting transistor Q2 is connected with collector electrode.
The two ends of current sense resistor R5 connect respectively the emitter of output transistor Q1 and the emitter of current detecting transistor Q2.
The negative pole of voltage stabilizing didoe ZD2 is connected with the collector electrode of output transistor Q1, and positive pole is connected with the emitter of current detecting transistor Q2.
In the present embodiment, the luminous component of optocoupler control module 22 converts the output current in current control module 24 to light signal, and the light accepting part of optocoupler control module 22 divides and converts light signal to the signal of telecommunication, and the signal of telecommunication is sent to switch power module 10.After the signal of telecommunication that switch power module 10 receives, switch power module 10 detects the electric current in current control module.Therefore, switch power module 10 is controlled the pressure drop of DC power supply according to the electric current detected and predetermined rated current.
Because the size of current in current control module 24 is directly proportional to the pressure drop size of DC power supply.Therefore, the electric current in current control module 24 is during higher than rated current, and the pressure drop that switch power module 10 is controlled the DC power supply of output reduces.Electric current in current control module 24 is during lower than rated current, and the pressure drop that switch power module 10 is controlled the DC power supply of output raises.
Particularly, the process that current sense resistor R5 detects electric current is: the electric current in current control module 24 is during higher than rated current, current detecting transistor Q2 conducting, and output transistor Q1 due to emitter junction pressure drop deficiency so that output transistor Q1 conducting.Thereby output transistor Q1 cut-off.And voltage stabilizing didoe ZD2 now is reversed and punctures in the voltage stabilizing state.Therefore, the current constant by current sense resistor R5 is not higher than rated current, and the pressure drop that the control signal of optocoupler control module 22 can not make switch power module 10 control DC power supply changes.
Electric current in current control module 24 is during higher than rated current, current detecting transistor Q2 conducting, voltage stabilizing didoe ZD2 is due to the increase of electric current in circuit, make voltage stabilizing didoe ZD2 be cut off, and increase by the electric current of current sense resistor R5, therefore, the pressure drop of output transistor Q1 emitter junction increases to the pressure drop that makes output transistor Q1 conducting, thus output transistor Q1 conducting.Thereby the electric current by optocoupler control module 22, output transistor Q1 and current sense resistor R5 is higher than rated current, the luminous component of optocoupler control module 22 becomes light signal by the current conversion in current control module 24, the light accepting part of optocoupler control module 22 divides and converts light signal to the signal of telecommunication, and the signal of telecommunication is sent to switch power module 10,10 pressure drops of controlling the DC power supply of output of switch power module reduce, thereby reduce the electric current in current control module 24, make it approach the rated current size.
Please in conjunction with Fig. 2.The square wave output module 14 that switch power module 10 comprises power transformation module 12, transformer T1 and controlled by feedback control module 20.
Power transformation module 12 input ac powers, output head anode are connected with transformer T1 primary coil one end, and the square wave output of square wave output module 14 is connected with the other end of transformer T1 primary coil.
Square wave output module 14 comprises pwm switch U1 and electrochemical capacitor C4, the drain electrode output of pwm switch U1 is connected with the primary coil of transformer T1 as the square wave output, the source electrode input end grounding of pwm switch U1, the control end input of pwm switch U1 divides the voltage of control by light accepting part, and by electrochemical capacitor C4 ground connection.
Square wave output module 14 also comprises second subprime coil, diode D2 and the filter capacitor C3 with the coupling of transformer T1 primary coil.Be connected in parallel on the two ends of second subprime coil after diode D2 and filter capacitor C3 series connection, and what be connected with an end of second subprime coil is the anode of diode D2, the other end ground connection of second subprime coil.
In the present embodiment, pwm switch U1 is specially TOP203Y.TOP203Y is the same with other products of TOP Switch series, and internal structure is basic identical.TOP203Y is packaged with 3 pins, is respectively source electrode input, drain electrode output and control end.
The input that control end is error amplifying circuit and feedback current.When normal operation, by the internal parallel adjuster, provide internal bias voltage.Control end mainly contains four functions: 1) utilize the size of controlling the IC electric current to regulate duty ratio; 2) provide the bias current of normal operation for chip; 3) determine the moving frequency of autoboot; 4) control loop is compensated.In the present embodiment, control the utmost point and be mainly used to the duty ratio of regulating of pwm switch U1 electric current, thereby reach the pressure drop size of control switch power module 10 out-put supplies.
Optocoupler feedback module 20 is optical coupler OP1, and optical coupler OP1 comprises light-emitting diode OP1A and triode OP1B.The light accepting part of optocoupler control module 22 is divided into triode OP1B, and the luminous component of optocoupler control module 22 is light-emitting diode OP1A.The positive pole of light-emitting diode OP1A is connected with DC power anode, and negative pole is connected with the collector electrode of output transistor Q1, and the collector electrode of triode OP1B is connected with the negative electrode of diode D2, and emitter is connected with the control end of pwm switch U1.
Optical coupler (optical coupler, english abbreviation is OC) also claim photoisolator or photoelectrical coupler, is called for short optocoupler.It is to take light as medium carrys out the device of transmission of electric signals, usually photophore (infrared light-emitting diode LED) and light-receiving device (photosensitive semiconductor pipe) is encapsulated in same shell.After input adds the signal of telecommunication, photophore emits beam, and light-receiving device is accepted just to produce photoelectric current after light, flows out from output, thereby has realized " electricity-light-electricity " conversion.The light of take is coupled to input end signal as medium the photoelectrical coupler of output, and insulation between output and input, the one-way transmission signal.In the present embodiment, optical coupler OP1 is mainly used to the size of current of monitoring current control module 24, and by " electrical-optical-electricity " conversion regime, the size of current in current control module 24 being fed back to switch power module 10, switch power module 10 is controlled the power voltage-drop size of output according to the size of current of feedback.
Current-limiting circuit based on Switching Power Supply also comprises divider resistance R2, and divider resistance R2 mono-end is connected with the negative pole of described light-emitting diode OP1A, and the other end is connected with the collector electrode of output transistor Q1.
Power transformation module 12 also comprises rectification module BR1, electrochemical capacitor C1, voltage stabilizing didoe ZD1 and diode D1.
Electrochemical capacitor C1 is anodal to be connected with the output of rectification module BR1, minus earth.
The positive pole of voltage stabilizing didoe ZD1 is connected with the output with rectification module BR1, and negative pole is connected with the negative pole of diode D1, and the positive pole of diode D1 is connected with the drain electrode of pwm switch U1.
The positive pole of diode D3 is connected with an end of transformer secondary output coil, and the negative pole of diode D3 is connected with the positive pole of DC power supply.
Current-limiting circuit based on Switching Power Supply also comprises inductance L 1, and an end of inductance L 1 is connected with the input of the luminous component of optocoupler control module 22, and the other end is connected with the collector electrode of current detecting transistor Q2.
Contact resistance R4 between the collector electrode of current detecting transistor Q2 and base stage, resistance R 4 changes for the saturation voltage drop that makes current detecting transistor Q2.The resistance value of resistance R 4 is very little, can be similar to think collector electrode and the base stage short circuit of current detecting transistor Q2.
Current-limiting circuit based on Switching Power Supply also comprises divider resistance R3, and divider resistance R3 mono-end is connected with DC power anode, and the other end is connected with the base stage of current detecting transistor Q2.
Particularly, output transistor Q1 is triode.Current detecting transistor Q2 is triode.
Current-limiting circuit based on Switching Power Supply also comprises electrochemical capacitor C5 and C6, and electrochemical capacitor C5 and C6 all are parallel to the DC power supply two ends.
Based on above-mentioned all embodiment, the operation principle of the current-limiting circuit based on Switching Power Supply as shown in Figure 2 is as follows:
Making the output limit electric current is I
lM, output current is I
o,, work as I
o<I
lMthe time, the DC power supply Vcc of switch power module 10 outputs is in areas of permanent pressure, and Vcc is substantially constant.Now current detecting transistor Q2 is operated in saturation region, and output transistor Q1 is the state of placing restrictions on, and the current-limiting function of the current-limiting circuit based on Switching Power Supply is inoperative.Particularly, be connected transformation between the collector electrode of current detecting transistor Q2 and base stage and fall resistance R 4, the resistance value of falling resistance R 4 due to transformation is very little, can be considered collector electrode and the base stage short circuit of current detecting transistor Q2, therefore, current detecting transistor Q2 always works in saturation region, and just saturation depth and saturation voltage drop VQ2s can change within the specific limits because the dividing potential drop of resistance R 4 falls in transformation.Output current I now
oless, pressure drop VR5 on current sense resistor R5 is lower, make emitter junction pressure drop Vbe1=VR5+VQ2s<0.65V of output transistor Q1, therefore, output transistor Q1 is the state of placing restrictions on, and is equivalent to open collector, to optocoupler control module 22 without shunting action, therefore, pwm switch U1 control output voltage is constant.
Work as I
o>I
lMthe time, because the pressure drop of the DC power supply VCC of output current IO and switch power module 10 outputs is proportional, therefore, the signal of telecommunication that the DC power supply Vcc of switch power module 10 outputs can receive according to pwm switch U1 reduce.Particularly, the now pressure drop on current sense resistor R5 is 0.3V, the saturation voltage drop VQ2s ≈ 0.57V of current detecting transistor Q2, and due to the emitter voltage drop Vbe1=VR5+VQ2s of output transistor Q1>0.7V, therefore, output transistor Q1 conducting.And exiting the voltage stabilizing district because of the reduction of Vcc, voltage stabilizing didoe ZD2 becomes cut-off state.Thereby arrive current sensing resistor R5 by the electric current of the LED output transistor Q1 that just flows through in optocoupler control module 22, because the conducting resistance of output transistor Q1 is very little, the pressure drop of getting is also little, thereby make the pressure drop on LED in optocoupler control module 22 increase, electric current by LED increases, the LED luminosity is strengthened, therefore, with the light accepting part in optocoupler control module 22, divide the pwm switch U1 control switch power module 10 be connected to enter restricted zone, the pressure drop that is the DC power supply Vcc of control switch power module 10 outputs reduces, thereby control IO, reduces.
The model of pwm switch U1 in switch power module 10 is TOP203Y, the control pin of TOP203Y is connected with the emitter of the triode of optocoupler control module 22, therefore, when the electric current of the LED that flows through increases, the voltage of the control pin of TOP203Y increases, thereby make the duty ratio of TOP203Y reduce, and the DC power supply Vcc exported by the drain electrode output control switch power module 10 of TOP203Y reduce.
Further analyze known, electric current on divider resistance R3 also is directly proportional to VCC, the continuation of Vcc reduces thereupon, and the electric current by divider resistance R3 reduces, and the saturation voltage drop VQ2s of current detecting transistor Q2 raises, the emitter junction pressure drop Vbe1 of output transistor Q1 increases, the electric current of LED of flowing through increases, and the voltage of the control pin of TOP203Y increases, thereby makes the duty ratio of TOP203Y reduce, the pressure drop that is the DC power supply Vcc of control switch power module 10 outputs reduces, and then control IO reduces.
As output current I
obe reduced to and be less than the output limit electric current I
lMthe time, the pressure drop on current sense resistor R5 reduces, and makes the emitter junction pressure drop Vbe1 of output transistor Q1 be less than 0.65V, therefore, output transistor Q1 cut-off, be equivalent to open collector, optocoupler control module 22 is not played to shunting action, and therefore, it is constant that TOP203Y controls output voltage.
The above embodiment has only expressed several execution mode of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection range of patent of the present invention should be as the criterion with claims.
Claims (8)
1. the current-limiting circuit based on Switching Power Supply, comprise the switch power module of exporting DC power supply, it is characterized in that, also comprises the feedback control module that is connected with switch power module and sends feedback control signal according to the output current of Switching Power Supply;
Described feedback control module comprises the optocoupler control module and for controlling the current control module of described output current size, the light accepting part of described optocoupler control module is tapped into described switch power module, and the electric current that the luminous component of described optocoupler control module accesses described current control module and luminous component is subject to the control of described current control module;
Described current control module comprises voltage stabilizing didoe, output transistor, current sense resistor and current detecting transistor; The output of the luminous component of described optocoupler control module is connected with the collector electrode of described output transistor, and the base stage of described output transistor is connected with the collector electrode of described current detecting transistor;
The collector electrode of described current detecting transistor is connected with described DC power anode, and the base stage of described current detecting transistor is connected with collector electrode;
The two ends of described current sense resistor connect respectively the emitter of described output transistor and the emitter of described current detecting transistor;
The negative pole of described voltage stabilizing didoe is connected with the collector electrode of described output transistor, anodally with the emitter of described current detecting transistor, is connected.
2. the current-limiting circuit based on Switching Power Supply according to claim 1, is characterized in that, the square wave output module that described switch power module comprises power transformation module, transformer T1 and controlled by described feedback control module,
Described power transformation module input ac power, output head anode are connected with described transformer T1 primary coil one end, and the square wave output of described square wave output module is connected with the other end of described transformer T1 primary coil;
Described square wave output module comprises pwm switch U1 and electrochemical capacitor C4, the drain electrode output of described pwm switch U1 is connected with the primary coil of transformer T1 as the square wave output, the source electrode input end grounding of described pwm switch U1, the control end input of described pwm switch U1 divides the voltage of control by described light accepting part, and by described electrochemical capacitor C4 ground connection;
Described square wave output module also comprises second subprime coil, diode D2 and the filter capacitor C3 with described transformer T1 primary coil coupling;
Be connected in parallel on the two ends of described second subprime coil after described diode D2 and filter capacitor C3 series connection, and what be connected with an end of second subprime coil is the anode of diode D2, the other end ground connection of second subprime coil;
Described optocoupler control module is optical coupler, and described optical coupler comprises light-emitting diode and triode, and the light accepting part of described optocoupler control module is divided into described triode, and the luminous component of described optocoupler control module is described light-emitting diode;
The positive pole of described light-emitting diode is connected with DC power anode, and negative pole is connected with the collector electrode of output transistor, and the collector electrode of described triode is connected with the negative electrode of described diode D2, and emitter is connected with the control end of described pwm switch U1.
3. the current-limiting circuit based on Switching Power Supply according to claim 2, it is characterized in that, the described current-limiting circuit based on Switching Power Supply also comprises divider resistance R2, and described divider resistance R2 mono-end is connected with the negative pole of described light-emitting diode, and the other end is connected with the collector electrode of described output transistor.
4. the current-limiting circuit based on Switching Power Supply according to claim 2, is characterized in that, described power transformation module comprises rectification module, electrochemical capacitor C1, voltage stabilizing didoe ZD1 and diode D1,
Described electrochemical capacitor C1 is anodal to be connected with the output of described rectification module, minus earth;
The positive pole of described voltage stabilizing didoe ZD1 with the output of described rectification module, be connected, negative pole is connected with the negative pole of described diode D1, the positive pole of described diode D1 is connected with the drain electrode of described pwm switch U1.
5. the current-limiting circuit based on Switching Power Supply according to claim 1, it is characterized in that, the described current-limiting circuit based on Switching Power Supply also comprises inductance L 1, one end of described inductance L 1 is connected with the input of the luminous component of described optocoupler control module, and the other end is connected with the collector electrode of described current detecting transistor.
6. the current-limiting circuit based on Switching Power Supply according to claim 1, is characterized in that, contact resistance R4 between the collector electrode of described current detecting transistor and base stage, and described resistance R 4 changes for the saturation voltage drop that makes described current detecting transistor.
7. the current-limiting circuit based on Switching Power Supply according to claim 1, it is characterized in that, the described current-limiting circuit based on Switching Power Supply also comprises divider resistance R3, and described divider resistance R3 mono-end is connected with DC power anode, and the other end is connected with the base stage of described current detecting transistor.
8. the current-limiting circuit based on Switching Power Supply according to claim 1, is characterized in that, the described current-limiting circuit based on Switching Power Supply also comprises electrochemical capacitor C5 and C6, and described electrochemical capacitor C5 and C6 all are parallel to the DC power supply two ends.
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| CN 201210173610 CN103457464A (en) | 2012-05-30 | 2012-05-30 | Current limiting circuit on basis of switching power supplies |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104661414A (en) * | 2015-03-05 | 2015-05-27 | 深圳快星半导体照明股份有限公司 | Constant-current driving device and starting method thereof |
| CN107135593A (en) * | 2017-06-07 | 2017-09-05 | 深圳市奥金瑞科技有限公司 | Intelligent switch is detected and identification circuit |
| CN111379893A (en) * | 2020-03-20 | 2020-07-07 | 青岛中加特电气股份有限公司 | Device for controlling electromagnetic valve |
| CN113533898A (en) * | 2021-07-23 | 2021-10-22 | 中国振华集团永光电子有限公司（国营第八七三厂） | Batch photoelectric coupler aging circuit |
-
2012
- 2012-05-30 CN CN 201210173610 patent/CN103457464A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104661414A (en) * | 2015-03-05 | 2015-05-27 | 深圳快星半导体照明股份有限公司 | Constant-current driving device and starting method thereof |
| CN107135593A (en) * | 2017-06-07 | 2017-09-05 | 深圳市奥金瑞科技有限公司 | Intelligent switch is detected and identification circuit |
| CN107135593B (en) * | 2017-06-07 | 2023-12-05 | 深圳市奥金瑞科技有限公司 | Intelligent switch detection and identification circuit |
| CN111379893A (en) * | 2020-03-20 | 2020-07-07 | 青岛中加特电气股份有限公司 | Device for controlling electromagnetic valve |
| CN113533898A (en) * | 2021-07-23 | 2021-10-22 | 中国振华集团永光电子有限公司（国营第八七三厂） | Batch photoelectric coupler aging circuit |
| CN113533898B (en) * | 2021-07-23 | 2023-07-14 | 中国振华集团永光电子有限公司（国营第八七三厂） | Aging circuit of batch photoelectric coupler |
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Application publication date: 20131218 |