CN102593946A - Dual-power-supply automatic switching circuit based on power MOSFET application - Google Patents
Dual-power-supply automatic switching circuit based on power MOSFET application Download PDFInfo
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Abstract
The invention relates to a dual-power automatic switching circuit based on power MOSFET application, which consists of a voltage detector, three triodes, two P-channel power MOSFETs, two diodes, two light-emitting diodes and a plurality of resistance elements. VIN1 and VIN2 are input ends of two groups of working power supplies, wherein VIN1 is connected with a main power supply, and VIN2 is connected with a standby power supply; VOUT is the output end of the power supply switching circuit and is connected with load equipment; GND is ground. In the working state, the main power supply and the standby power supply are powered on simultaneously, and VIN1= VIN 2. A voltage dividing resistor is added at the detection end of the voltage detector, so that the detected voltage is close to the detection threshold value as much as possible. When the voltage of the main power supply drops, the voltage detector can be driven at the first time to finish the automatic switching work of the power supply. The invention combines the working characteristics of the power MOSFET, cooperates with the voltage detector, adopts the power MOSFET as a change-over switch, and can automatically switch the standby power supply when the voltage of the main power supply is reduced below the threshold voltage set by the power detector or the power is cut off.
Description
Technical field
The present invention relates to a kind of power supply automatic switchover circuit, a kind of specifically double supply automatic switch-over circuit of using based on power MOSFET.
Background technology
Usually the application of some key equipments need be provided with stand-by power supply, and during undesired or outage, stand-by power supply will automatically switch incessantly, to guarantee the operate as normal of equipment when main power source.The most frequently used way is that relay switches and diode parallel connection switching mode, but all there is drawback in these two kinds of switching modes.It at first is problem switching time; Usually the reaction time of relay all is the ms level; This just need be equipped with enough jumbo storage capacitor at power end restarts in the power supply handoff procedure to prevent equipment, and obviously this is unpractical in the bigger occasion of equipment applied current; Next is a problem of pressure drop; The diode parallel way all brings problem can for two passages of primary and secondary; The tube voltage drop of diode can cause that supply power voltage is low excessively to cause unit exception, particularly at some low voltage operating occasions (like 5V, 3.3V), so typical diode pressure drop (0.7V) can make the power supply supply power voltage low excessively; Memory IC tolerance limit problem to the low-tension supply power supply is more serious; Even (0.2V～0.5V) and so on lower diode of pressure drop also just makes situation make moderate progress to a certain extent, can't resolve root problem to use Schottky diode.
Summary of the invention
Technical problem to be solved by this invention is; Overcome above prior art and mention two technical problems, a kind of double supply automatic switch-over circuit of using based on power MOSFET is provided, in conjunction with the operating characteristic of power MOSFET; Cooperate voltage detector; Adopt power MOSFET to do diverter switch, below main power voltage drops to the threshold voltage that Power supply detector sets or during outage, stand-by power supply can automatically switch.
The technical scheme that the present invention solves above technical problem is:
Double supply automatic switch-over circuit based on the power MOSFET application; The input VIN1 and the VIN2 that comprise two working powers, a voltage detector U1, three triode T1, T2 and T3; Two P channel power MOS FETQ2 and Q4, two diode Q1 and Q3 and resistance; Working power goes into to hold VIN1 to connect the output of main electricity, and working power goes into to hold VIN2 to connect the output of stand-by power supply power supply; Working power goes into to hold VIN1 to pass through resistance R 1 earth connection GND; Resistance R 1 plays the effect of repid discharge; Guarantee when power supply switches, accomplish the power supply switch operating thereby the input terminal voltage of voltage detector U1 can drop to the level translation of drive output below the threshold values in the shortest time; Working power goes into to hold VIN2 to pass through resistance R 2 earth connection GND, and working power goes into to hold VIN2 to pass through resistance R 5 and R6 earth connection GND, simultaneously the base stage of the connection termination triode T3 of resistance R 5 and resistance R 6; Working power goes into to hold VIN1 to pass through resistance R 9 and R10 earth connection GND; The 2 pin inputs of the connection termination voltage detector U1 of while resistance R 9 and resistance R 10; The effect of resistance R 9 and resistance R 10 is dividing potential drops; Adjust to the 2 pin input terminal voltages of voltage detector U1 as far as possible near threshold values, guarantee in the shortest time, to accomplish level translation; The 3 pin earth connection GND of voltage detector U1; The base stage of 1 pin output termination triode T1 also connects working power through pull-up resistor R3 simultaneously and goes into to hold VIN1, and through pull down resistor R4 earth connection GND; Wherein the effect of resistance R 3 is to guarantee that voltage detector U1 is under idle situation; Output keeps high level (exporting because voltage detector is out to leak, so this pull-up resistor is necessary), and resistance R 4 plays the effect of dividing potential drop and discharge; Working power goes into to hold VIN1 finally to receive the drain electrode of positive pole and the power MOSFET Q2 of diode Q1; The collector electrode of triode T1 connects the grid of power MOSFET Q2; The negative pole that meets source electrode and the diode Q1 of power MOSFET Q2 through resistance R 7 simultaneously also is the output VOUT of entire circuit simultaneously; Wherein diode Q1 and power MOSFET Q2 parallel connection shield, and resistance R 7 is to guarantee that the grid of power MOSFET Q2 when triode T1 ends and source electrode keep the equipotential cut-off state; The emitter of triode T1 connects the base stage of triode T2; The grounded collector line GND of triode T2, the emitter of triode T2 connects the base stage of triode T3, and the grid that the collector electrode of triode T3 meets power MOSFET Q4 simultaneously also connects the source electrode of power MOSFET Q4 through resistance R 8 and the negative pole while of diode Q3 also is the output VOUT of entire circuit; These three triode T1, T2 and T3 coupled in series are used for the Guarantee Status interlock; In the time of triode T1 conducting, also conducting of triode T2, triode T3 ends; Drag down the grid level of power MOSFET Q2 simultaneously; The grid level of raising power MOSFET Q4 ends power MOSFET Q2 conducting power MOSFET Q4, and equipment goes into to hold the VIN1 power supply by working power, and working power goes into to hold VIN2 to stop power supply; Opposite triode T1 ends when voltage detector U1 detects low level, and triode T2 also ends; Triode T3 conducting; At this moment the grid of power MOSFET Q2 and source electrode equipotential are ended, and the grid level of power MOSFET Q4 is drawn as low level, and the power supply switching is accomplished in power MOSFET Q4 conducting; Equipment goes into to hold the VIN2 power supply by working power, and working power goes into to hold VIN1 to stop power supply.
Two main effects with the power MOSFET diode connected in parallel have two, at first are to play subsequent use effect, and under the situation of power MOSFET damage or cisco unity malfunction, power supply can be through diode directly to power devices, and assurance equipment does not cut off the power supply; Next is to play a protective role, and when power supply passes through diode when power consumption equipment is directly supplied power, utilizes the diode reverse cut-off characteristics to prevent that effectively the electric current between the duplicate supply from pouring in down a chimney the damage power supply.
Like this, when the detected voltage in voltage detector U1 test side detected threshold voltage greater than it, then its output ended; Through pull-up resistor R3 output high level, this high level makes triode T1 saturation conduction, thereby makes also saturation conduction of triode T2; Finally making the grid of power MOSFET Q2 and the base stage of triode T3 all is low level, and triode T3 ends, and the grid of power MOSFET Q4 and source electrode equipotential are ended; Source current flows to the source electrode of power MOSFET Q4 through heavy-duty diode; The source voltage that the source voltage of power MOSFET Q2 equals power MOSFET Q4 approximates the pressure drop that main electricity voltage deducts diode, because the grid of power MOSFET Q2 is a low level, and power MOSFET Q2 saturation conduction; Because power MOSFET Q4 ends; The conducting resistance of power MOSFET Q2 is very little, and its tube voltage drop is much little more than the pressure drop of diode connected in parallel, so main power source is supplied power to load equipment through power MOSFET Q2;
When main power voltage decline causes the detected voltage in voltage detector U1 test side to detect threshold voltage less than it, the conducting of voltage detector U1 output, output low level; This low level is ended triode T1; Thereby triode T2 is also ended, and finally making the grid of power MOSFET Q2 and the base stage of triode T3 all is high level, and the grid of power MOSFET Q2 and source electrode equipotential are ended; Triode T3 saturation conduction; The grid that makes power MOSFET Q4 is a low level, and the stand-by power supply electric current flows to the source electrode of power MOSFET Q4 through diode, approximates the pressure drop that backup power source voltage deducts diode so the source voltage of power MOSFET Q4 equals the source voltage of power MOSFET Q2; And because the grid of power MOSFET Q4 is a low level; Power MOSFET Q4 saturation conduction, because power MOSFET Q2 ends, the conducting resistance of power MOSFET Q4 is very little; Its tube voltage drop is much little more than the pressure drop of diode connected in parallel, so stand-by power supply is supplied power to load equipment through power MOSFET Q2;
When primary power source de-energizes, the voltage detector test side does not have input voltage, and output is forced to low level through pull down resistor, and triode T1 ends equally, the situation basically identical that its working condition and top voltage descend.
The technical scheme that the present invention further limits is:
The aforesaid double supply automatic switch-over circuit of using based on power MOSFET, the threshold values of voltage detector U1 selects to be lower than power supply nominal output voltage values 0.5V.Consider that power supply inserts the possibility that possibly exist output voltage slightly to descend after the load; Also to consider simultaneously the reasonable domain of walker of voltage detector detection threshold, select to be lower than about power supply nominal output voltage values 0.5V to be advisable so the threshold values of voltage detector U1 is general.Because generally; Magnitude of voltage all can have the decline of certain amplitude after power supply inserts load; So when selecting voltage detection device, must consider this point; Thereby output that magnitude of voltage just drops to driving voltage detector below the detection threshold is in low level state always if selected for use the too high detection means of detection threshold might cause main power source just to begin to switch on; So main electricity just is in off state, and equipment can only be supplied power by stand-by power supply, and commutation circuit is ineffective.
The aforesaid double supply automatic switch-over circuit of using based on power MOSFET, voltage detector U1 selects HT7044, and the detection threshold voltage is 4.4V.
The aforesaid double supply automatic switch-over circuit of using based on power MOSFET; Working power goes into to hold the positive pole of VIN1 through current-limiting resistance R11 sending and receiving optical diode L1; The minus earth line GND of light-emitting diode L1; Resistance R 11 is used to limit the size of current that flows through light-emitting diode L1, guarantees that light-emitting diode L1 is operated in the safe current scope; Working power goes into to hold the positive pole of VIN2 through current-limiting resistance R12 sending and receiving optical diode L2; The minus earth line GND of light-emitting diode L2; Resistance R 12 is used to limit the size of current that flows through light-emitting diode L2, guarantees that light-emitting diode L2 is operated in the safe current scope; Two light-emitting diodes have been used for indicative function, and following two light-emitting diodes of normal operation are all lighted, and are when any one road power supply wherein takes place when unusual, corresponding that light-emitting diode extinguish prompting on-call maintenance or replacement.
The invention has the beneficial effects as follows: the present invention combines the operating characteristic of power MOSFET; Adopt power MOSFET to do diverter switch; Cooperate voltage detector; Below main power voltage drops to the threshold voltage that Power supply detector sets or during outage, stand-by power supply can automatically switch, and mentions two problems above can solving simultaneously.At first, the switching frequency of MOSFET is fast (ns level) very, can accomplish that fully equipment work uninterruptedly automaticallyes switch; Secondly, the tube voltage drop of MOSFET is extremely low, can be controlled at basically in the 0.1V, and part of devices even can accomplish in the 50mV, can accomplish basically that supply voltage is harmless switches., power consumption equipment supplies power when powering on for the first time by main power source; When in case main electricity takes place to fall unusually or cuts off the power supply in the equipment work process; Can keep automatically switching to the stand-by power supply power supply under the impregnable situation of equipment operate as normal; After main electricity recovers normally, can uninterruptedly automatically switch to the main power source power supply by stand-by power supply more equally, can guarantee not power down of power supply unit in the handoff procedure, not restart.
Description of drawings
Fig. 1 is a circuit diagram of the present invention.
Embodiment
Present embodiment provides a kind of double supply automatic switch-over circuit of using based on power MOSFET; Circuit is as shown in Figure 1; The input VIN1 and the VIN2 that comprise two working powers, a voltage detector U1, three triode T1, T2 and T3; Two P channel power MOS FETQ2 and Q4, two diode Q1 and Q3 and resistance; Working power goes into to hold VIN1 to connect the output of main electricity, and working power goes into to hold VIN2 to connect the output of stand-by power supply power supply; Working power goes into to hold the positive pole of VIN1 through current-limiting resistance R11 sending and receiving optical diode L1; The minus earth line GND of light-emitting diode L1; Resistance R 11 is used to limit the size of current that flows through light-emitting diode L1, guarantees that light-emitting diode L1 is operated in the safe current scope; Working power goes into to hold the positive pole of VIN2 through current-limiting resistance R12 sending and receiving optical diode L2; The minus earth line GND of light-emitting diode L2; Resistance R 12 is used to limit the size of current that flows through light-emitting diode L2, guarantees that light-emitting diode L2 is operated in the safe current scope; Two light-emitting diodes have been used for indicative function, and following two light-emitting diodes of normal operation are all lighted, and are when any one road power supply wherein takes place when unusual, corresponding that light-emitting diode extinguish prompting on-call maintenance or replacement; Working power goes into to hold VIN1 to pass through resistance R 1 earth connection GND; Resistance R 1 plays the effect of repid discharge; Guarantee when power supply switches, accomplish the power supply switch operating thereby the input terminal voltage of voltage detector U1 can drop to the level translation of drive output below the threshold values in the shortest time; Working power goes into to hold VIN2 to pass through resistance R 2 earth connection GND, and working power goes into to hold VIN2 to pass through resistance R 5 and R6 earth connection GND, simultaneously the base stage of the connection termination triode T3 of resistance R 5 and resistance R 6; Working power goes into to hold VIN1 to pass through resistance R 9 and R10 earth connection GND; The 2 pin inputs of the connection termination voltage detector U1 of while resistance R 9 and resistance R 10; The effect of resistance R 9 and resistance R 10 is dividing potential drops; Adjust to the 2 pin input terminal voltages of voltage detector U1 as far as possible near threshold values, guarantee in the shortest time, to accomplish level translation; The 3 pin earth connection GND of voltage detector U1; The base stage of 1 pin output termination triode T1 also connects working power through pull-up resistor R3 simultaneously and goes into to hold VIN1, and through pull down resistor R4 earth connection GND; Wherein the effect of resistance R 3 is to guarantee that voltage detector U1 is under idle situation; Output keeps high level (exporting because voltage detector is out to leak, so this pull-up resistor is necessary), and resistance R 4 plays the effect of dividing potential drop and discharge; Working power goes into to hold VIN1 finally to receive the drain electrode of positive pole and the power MOSFET Q2 of diode Q1; The collector electrode of triode T1 connects the grid of power MOSFET Q2; The negative pole that meets source electrode and the diode Q1 of power MOSFET Q2 through resistance R 7 simultaneously also is the output VOUT of entire circuit simultaneously; Wherein diode Q1 and power MOSFET Q2 parallel connection shield, and resistance R 7 is to guarantee that the grid of power MOSFET Q2 when triode T1 ends and source electrode keep the equipotential cut-off state; The emitter of triode T1 connects the base stage of triode T2; The grounded collector line GND of triode T2, the emitter of triode T2 connects the base stage of triode T3, and the grid that the collector electrode of triode T3 meets power MOSFET Q4 simultaneously also connects the source electrode of power MOSFET Q4 through resistance R 8 and the negative pole while of diode Q3 also is the output VOUT of entire circuit; These three triode T1, T2 and T3 coupled in series are used for the Guarantee Status interlock; In the time of triode T1 conducting, also conducting of triode T2, triode T3 ends; Drag down the grid level of power MOSFET Q2 simultaneously; The grid level of raising power MOSFET Q4 ends power MOSFET Q2 conducting power MOSFET Q4, and equipment goes into to hold the VIN1 power supply by working power, and working power goes into to hold VIN2 to stop power supply; Opposite triode T1 ends when voltage detector U1 detects low level, and triode T2 also ends; Triode T3 conducting; At this moment the grid of power MOSFET Q2 and source electrode equipotential are ended, and the grid level of power MOSFET Q4 is drawn as low level, and the power supply switching is accomplished in power MOSFET Q4 conducting; Equipment goes into to hold the VIN2 power supply by working power, and working power goes into to hold VIN1 to stop power supply.Two main effects with the power MOSFET diode connected in parallel have two, at first are to play subsequent use effect, and under the situation of power MOSFET damage or cisco unity malfunction, power supply can be through diode directly to power devices, and assurance equipment does not cut off the power supply; Next is to play a protective role, and when power supply passes through diode when power consumption equipment is directly supplied power, utilizes the diode reverse cut-off characteristics to prevent that effectively the electric current between the duplicate supply from pouring in down a chimney the damage power supply.
Consider that power supply inserts the possibility that possibly exist output voltage slightly to descend after the load; Also to consider simultaneously the reasonable domain of walker of voltage detector detection threshold, select to be lower than about power supply nominal output voltage values 0.5V to be advisable so the threshold values of voltage detector U1 is general.Press detector U1 to select HT7044, the detection threshold voltage is 4.4V.Because generally; Magnitude of voltage all can have the decline of certain amplitude after power supply inserts load; So when selecting voltage detection device, must consider this point; Thereby output that magnitude of voltage just drops to driving voltage detector below the detection threshold is in low level state always if selected for use the too high detection means of detection threshold might cause main power source just to begin to switch on; So main electricity just is in off state, and equipment can only be supplied power by stand-by power supply, and commutation circuit is ineffective.
Main power voltage normal (VIN1=5V):
Working power goes into to hold the voltage of VIN1 to make light-emitting diode L1 light (indicate this road power supply normal), and working power goes into to hold the voltage of VIN2 to make light-emitting diode L2 light (indicate this road power supply normal).Voltage detector U1 leaves Lou output device (effectively low) for the CMOS type; Resistance R 3 is a pull-up resistor, and the detection threshold voltage of voltage detector U1 is 4.4V, when the detected voltage in its test side (2 pin) during greater than 4.4V; Then the inner metal-oxide-semiconductor of its output (1 pin) ends; Through pull-up resistor R3 output high level, this high level makes triode T1 saturation conduction, and the emitter of triode T1 links to each other with the base stage of triode T2; Thereby make also saturation conduction of triode T2, finally making the grid of power MOSFET Q2 and the base stage of triode T3 all is low level.Triode T3 ends, and the grid of power MOSFET Q4 and source electrode equipotential are ended; Source current flows to the source electrode of power MOSFET Q4 through heavy-duty diode, approximates the pressure drop (5V-0.7V=4.3V) that main power voltage (or backup power source voltage) deducts heavy-duty diode so the source voltage of power MOSFET Q2 equals the source voltage of power MOSFET Q4.And because the grid of power MOSFET Q2 is a low level; So-VGS--≈ 4.3V; Power MOSFET Q2 saturation conduction, because power MOSFET Q4 ends, the conducting resistance of power MOSFET Q2 is very little; Its tube voltage drop is much little more than the pressure drop of the heavy-duty diode of parallel connection, so main power source is supplied power to load equipment through power MOSFET Q2.
Main power voltage descends or outage:
The inner metal-oxide-semiconductor conducting of voltage detector U1 output (1 pin) when main power voltage decline causes the detected voltage in voltage detector U1 test side (2 pin) less than 4.4V, output low level.This low level is ended triode T1, and the emitter of triode T1 links to each other with the base stage of triode T2, thereby triode T2 is also ended, and finally making the grid of power MOSFET Q2 and the base stage of triode T3 all is high level.The grid of power MOSFET Q2 and source electrode equipotential are ended; Triode T3 saturation conduction; The grid that makes power MOSFET Q4 is a low level; The stand-by power supply electric current flows to the source electrode of power MOSFET Q4 through diode, approximates the pressure drop (5V-0.7V=4.3V) that backup power source voltage deducts diode so the source voltage of power MOSFET Q4 equals the source voltage of power MOSFET Q2.And because the grid of power MOSFET Q4 is a low level; So-VGS--≈ 4.3V; Power MOSFET Q4 saturation conduction, because power MOSFET Q2 ends, the conducting resistance of power MOSFET Q4 is very little; Its tube voltage drop is much little more than the pressure drop of diode connected in parallel, so stand-by power supply is supplied power to load equipment through power MOSFET Q2.
When primary power source de-energizes, light-emitting diode L1 extinguishes, and the voltage detector test side does not have input voltage, and output is forced to low level through pull down resistor, and triode T1 ends equally, the situation basically identical that its working condition and top voltage descend.
Except that the foregoing description, the present invention can also have other execution modes.All employings are equal to the technical scheme of replacement or equivalent transformation formation, all drop on the protection range of requirement of the present invention.
Claims (4)
1. the double supply automatic switch-over circuit of using based on power MOSFET; It is characterized in that: comprise the input VIN1 and the VIN2 of two working powers, a voltage detector U1, three triode T1, T2 and T3; Two P channel power MOS FETQ2 and Q4, two diode Q1 and Q3 and resistance; Said working power goes into to hold VIN1 to connect the output of main electricity, and working power goes into to hold VIN2 to connect the output of stand-by power supply power supply; Said working power goes into to hold VIN1 to pass through resistance R 1 earth connection GND; Resistance R 1 plays the effect of repid discharge; Guarantee when power supply switches, accomplish the power supply switch operating thereby the input terminal voltage of voltage detector U1 can drop to the level translation of drive output below the threshold values in the shortest time; Said working power goes into to hold VIN2 to pass through resistance R 2 earth connection GND, and said working power goes into to hold VIN2 to pass through resistance R 5 and R6 earth connection GND, simultaneously the base stage of the connection termination triode T3 of resistance R 5 and resistance R 6; Said working power goes into to hold VIN1 to pass through resistance R 9 and R10 earth connection GND; The 2 pin inputs of the connection termination voltage detector U1 of while resistance R 9 and resistance R 10; The effect of resistance R 9 and resistance R 10 is dividing potential drops; Adjust to the 2 pin input terminal voltages of voltage detector U1 as far as possible near threshold values, guarantee in the shortest time, to accomplish level translation; The 3 pin earth connection GND of voltage detector U1; The base stage of 1 pin output termination triode T1; Simultaneously also connect working power and go into to hold VIN1, and through pull down resistor R4 earth connection GND, wherein the effect of resistance R 3 is to guarantee that voltage detector U1 is under idle situation through pull-up resistor R3; Output keeps high level, and resistance R 4 plays the effect of dividing potential drop and discharge; Working power goes into to hold VIN1 finally to receive the drain electrode of positive pole and the power MOSFET Q2 of diode Q1; The collector electrode of triode T1 connects the grid of power MOSFET Q2; The negative pole that meets source electrode and the diode Q1 of power MOSFET Q2 through resistance R 7 simultaneously also is the output VOUT of entire circuit simultaneously; Wherein diode Q1 and power MOSFET Q2 parallel connection shield, and resistance R 7 is to guarantee that the grid of power MOSFET Q2 when triode T1 ends and source electrode keep the equipotential cut-off state; The emitter of triode T1 connects the base stage of triode T2; The grounded collector line GND of triode T2, the emitter of triode T2 connects the base stage of triode T3, and the grid that the collector electrode of triode T3 meets power MOSFET Q4 simultaneously also connects the source electrode of power MOSFET Q4 through resistance R 8 and the negative pole while of diode Q3 also is the output VOUT of entire circuit; These three triode T1, T2 and T3 coupled in series are used for the Guarantee Status interlock; In the time of triode T1 conducting, also conducting of triode T2, triode T3 ends; Drag down the grid level of power MOSFET Q2 simultaneously; The grid level of raising power MOSFET Q4 ends power MOSFET Q2 conducting power MOSFET Q4, and equipment goes into to hold the VIN1 power supply by working power, and working power goes into to hold VIN2 to stop power supply; Opposite triode T1 ends when voltage detector U1 detects low level, and triode T2 also ends; Triode T3 conducting; At this moment the grid of power MOSFET Q2 and source electrode equipotential are ended, and the grid level of power MOSFET Q4 is drawn as low level, and the power supply switching is accomplished in power MOSFET Q4 conducting; Equipment goes into to hold the VIN2 power supply by working power, and working power goes into to hold VIN1 to stop power supply.
2. the double supply automatic switch-over circuit of using based on power MOSFET as claimed in claim 1 is characterized in that: the threshold values of said voltage detector U1 selects to be lower than power supply nominal output voltage values 0.5V.
3. the double supply automatic switch-over circuit of using based on power MOSFET as claimed in claim 2 is characterized in that: said voltage detector U1 selects HT7044, and the detection threshold voltage is 4.4V.
4. the double supply automatic switch-over circuit of using based on power MOSFET as claimed in claim 1; It is characterized in that: said working power goes into to hold the positive pole of VIN1 through current-limiting resistance R11 sending and receiving optical diode L1; The minus earth line GND of light-emitting diode L1; Resistance R 11 is used to limit the size of current that flows through light-emitting diode L1, guarantees that light-emitting diode L1 is operated in the safe current scope; Said working power goes into to hold the positive pole of VIN2 through current-limiting resistance R12 sending and receiving optical diode L2; The minus earth line GND of light-emitting diode L2; Resistance R 12 is used to limit the size of current that flows through light-emitting diode L2, guarantees that light-emitting diode L2 is operated in the safe current scope; Two light-emitting diodes have been used for indicative function, and following two light-emitting diodes of normal operation are all lighted, and are when any one road power supply wherein takes place when unusual, corresponding that light-emitting diode extinguish prompting on-call maintenance or replacement.
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| CN108957108A (en) * | 2018-08-17 | 2018-12-07 | 无锡麟力科技有限公司 | A kind of mains failure detection circuit |
| CN109428385A (en) * | 2017-08-29 | 2019-03-05 | 中兴通讯股份有限公司 | Power transfer system and method |
| CN112003363A (en) * | 2020-08-03 | 2020-11-27 | 哈尔滨新中新电子股份有限公司 | Embedded power system management circuit |
| CN113467335A (en) * | 2021-07-30 | 2021-10-01 | 苏州浪潮智能科技有限公司 | Power supply control circuit, power supply control device and server |
| CN115085336A (en) * | 2022-07-22 | 2022-09-20 | 深圳市创芯微微电子有限公司 | Dynamic load circuit for charging equipment, dynamic load adjusting method and charging equipment |
| CN108879892B (en) * | 2018-09-20 | 2024-04-19 | 山东思科赛德矿业安全工程有限公司 | Automatic switching power supply system for double battery packs |
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| CN104218665A (en) * | 2013-05-31 | 2014-12-17 | 英业达科技有限公司 | A power supply apparatus and a method for switching the same |
| CN106712139A (en) * | 2015-08-24 | 2017-05-24 | 重庆宁来科贸有限公司 | Timing type N constant current charger |
| CN106569431A (en) * | 2015-10-13 | 2017-04-19 | 奉化市威克电子厂 | Single chip microcomputer I/O interface multiplexing circuit |
| CN107069937A (en) * | 2017-04-25 | 2017-08-18 | 航天科技控股集团股份有限公司 | Automatic change-over device of emergency |
| CN109428385A (en) * | 2017-08-29 | 2019-03-05 | 中兴通讯股份有限公司 | Power transfer system and method |
| CN107591777A (en) * | 2017-10-02 | 2018-01-16 | 佛山中锦微电科技有限公司 | Overcurrent protective power driving circuit and motor-drive circuit |
| CN107591777B (en) * | 2017-10-02 | 2020-09-15 | 佛山中锦微电科技有限公司 | Overcurrent protection type power drive circuit and motor drive circuit |
| CN108258904A (en) * | 2017-12-01 | 2018-07-06 | 珠海格力电器股份有限公司 | DC power supply and its method of supplying power to |
| CN108808845A (en) * | 2018-08-14 | 2018-11-13 | 广州奥格智能科技有限公司 | A kind of ultra-low loss double loop power supply switching anti-back flow circuit |
| CN108957108A (en) * | 2018-08-17 | 2018-12-07 | 无锡麟力科技有限公司 | A kind of mains failure detection circuit |
| CN108957108B (en) * | 2018-08-17 | 2024-03-12 | 无锡麟力科技有限公司 | Commercial power outage detection circuit |
| CN108879892A (en) * | 2018-09-20 | 2018-11-23 | 山东思科赛德矿业安全工程有限公司 | A kind of double cell group automatic switchover power supply system |
| CN108879892B (en) * | 2018-09-20 | 2024-04-19 | 山东思科赛德矿业安全工程有限公司 | Automatic switching power supply system for double battery packs |
| CN112003363A (en) * | 2020-08-03 | 2020-11-27 | 哈尔滨新中新电子股份有限公司 | Embedded power system management circuit |
| CN113467335A (en) * | 2021-07-30 | 2021-10-01 | 苏州浪潮智能科技有限公司 | Power supply control circuit, power supply control device and server |
| CN115085336A (en) * | 2022-07-22 | 2022-09-20 | 深圳市创芯微微电子有限公司 | Dynamic load circuit for charging equipment, dynamic load adjusting method and charging equipment |
| CN115085336B (en) * | 2022-07-22 | 2022-12-06 | 深圳市创芯微微电子有限公司 | Dynamic load circuit for charging equipment, dynamic load adjusting method and charging equipment |
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