CN116827084A - Parallel circuit - Google Patents
Parallel circuit Download PDFInfo
- Publication number
- CN116827084A CN116827084A CN202310796423.8A CN202310796423A CN116827084A CN 116827084 A CN116827084 A CN 116827084A CN 202310796423 A CN202310796423 A CN 202310796423A CN 116827084 A CN116827084 A CN 116827084A
- Authority
- CN
- China
- Prior art keywords
- control module
- switching tube
- output end
- output
- tube
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 abstract description 2
- 230000000694 effects Effects 0.000 description 3
- 230000005669 field effect Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Landscapes
- Electronic Switches (AREA)
Abstract
The application discloses a parallel circuit, which is applied to a switching power supply, and comprises: the short circuit control module pulls down the voltage of the control signal end when the load is short-circuited, so that the first output control module and the second output control module are turned off. The application can not only be used for parallel connection of the switching power supplies of the two units, but also realize self-locking; short-circuit protection can be performed according to application conditions; realizing the energy disconnection of a short-circuit current loop; meanwhile, the circuit has the characteristics of simple circuit structure, accurate control method and lower cost.
Description
Technical Field
The application relates to the technical field of electronic circuits, in particular to a parallel circuit.
Background
The parallel circuit of the switching power supply is formed by connecting output ends of power supplies of two units in parallel through a parallel circuit, and aims to share load power together, and the basic principle is as follows: under normal conditions, the switching power supplies of the two units are output in parallel, the load and the current are equally divided, and when one power supply fails, the rest power supply bears all loads, and the load is 1+1 parallel redundancy; the nature of parallel redundancy is that the uninterrupted power supply equally divides the load; this patent only describes the parallel circuit section;
the current common parallel circuit is characterized in that NMOS control is arranged at the forward input ends of two units, but because of NMOS characteristics, the grid voltage needs additional bootstrap voltage, so that the grid voltage is larger than the source voltage, the source voltage is the direct current input end of the switching power supply, and the VGS voltage is ensured to be larger than the threshold voltage so as to be conducted, and the mode needs additional bootstrap circuit and has no advantage; the common situation of the parallel circuit is that NMOS control is placed at the negative input ends of the two units, so that the VGS voltage is conducted more than the threshold voltage; however, in the case of a short circuit, the energy I2*R generated by the short circuit current flowing from the positive terminal to the negative terminal can cause the switching tube to have too much transient energy to fail, and the parallel circuit cannot work properly.
The short-circuit protection function of the switching power supply is one of main indexes of the switching power supply, and is used for protecting short-circuit faults generated by electrical short-circuit in the switching power supply, and most of the switching power supplies have the short-circuit protection function. Meanwhile, different short-circuit protection modes are set according to different conditions, generally, under the condition that an output end is short-circuited, the PWM control circuit can limit the output current within a safe range, the current limiting circuit can be realized by a plurality of methods, and when the power current limiting is not effective in the short-circuit, only a part of circuits are additionally arranged for short-circuit protection. However, the existing control mode, device composition, cost, structure and performance of the short circuit have no advantages. The prior art has the following characteristics:
the current common short-circuit protection widely adopts a circuit scheme that a controller limits current to perform protection, the short-circuit protection scheme is a principle of actual overcurrent, and the control mode can also cooperate with a current-limiting resistor of a primary MOSFET to control maximum output power to realize short-circuit protection.
Disclosure of Invention
Therefore, the application aims to provide a parallel circuit, which can realize normal parallel use of two-unit switching power supplies, and can realize self-locking of the parallel circuit when a short circuit condition is realized, and realize circuit turn-off, so that the effect of generating huge energy by a current circuit after the short circuit is disconnected is achieved.
In order to achieve the above purpose, the present application adopts the following technical scheme:
a parallel circuit for use in a switching power supply, the parallel circuit comprising:
the first input end of the first output control module is connected to the positive electrode output end of the first switching power supply, the second input end of the first output control module is connected to the negative electrode output end of the first switching power supply, the third input end of the first output control module is connected to the control signal end, and the positive electrode output end of the first output control module is connected to the positive electrode output end of the parallel circuit;
the first input end of the second output control module is connected to the positive electrode output end of the second switching power supply, the second input end of the second output control module is connected to the negative electrode output end of the second switching power supply, the third input end of the second output control module is connected to the control signal end, and the positive electrode output end of the second output control module is connected to the positive electrode output end of the parallel circuit;
the input end of the short circuit control module is connected to the positive electrode output end of the parallel circuit, the output end of the short circuit control module is connected to the negative electrode output end of the parallel circuit, and the short circuit control module is also respectively connected to a control signal end, the negative electrode output end of the first output control module and the negative electrode output end of the second output control module;
when the load is short-circuited, the short-circuit control module pulls down the voltage of the control signal end, so that the first output control module and the second output control module are turned off.
In an exemplary embodiment of the present application, the first output control module includes a first resistor, a second resistor, a first switching tube, and a second switching tube, where a source electrode of the first switching tube is connected to an anode output terminal of the first switching power supply, a gate electrode of the first switching tube is connected to a drain electrode of the second switching tube through the first resistor, a source electrode of the second switching tube is connected to a cathode output terminal of the first switching power supply, a gate electrode of the second switching tube is connected to a control signal terminal through the second resistor, a drain electrode of the first switching tube is connected to an anode output terminal of the parallel circuit, and a drain electrode of the second switching tube is connected to the short circuit control module.
In an exemplary embodiment of the present application, the second output control module includes a third resistor, a fourth resistor, a third switching tube and a fourth switching tube, where a source electrode of the third switching tube is connected to an anode output end of the second switching power supply, a gate electrode of the third switching tube is connected to a drain electrode of the fourth switching tube through the third resistor, a source electrode of the fourth switching tube is connected to a cathode output end of the second switching power supply, a gate electrode of the fourth switching tube is connected to a control signal end through the fourth resistor, a drain electrode of the third switching tube is connected to an anode output end of the parallel circuit, and a drain electrode of the fourth switching tube is connected to the short circuit control module.
In an exemplary embodiment of the present application, the short circuit control module includes a fifth resistor, a sixth resistor, and a fifth switching tube, where a gate of the fifth switching tube is connected to the control signal terminal through the sixth resistor, a gate of the fifth switching tube is connected to the positive output terminal of the parallel circuit through the fifth resistor, a source of the fifth switching tube is connected to the negative output terminal of the first output control module and the negative output terminal of the second output control module, respectively, and a drain of the fifth switching tube is connected to the negative output terminal of the parallel circuit.
In an exemplary embodiment of the present application, the first switching tube is a PMOS tube, and the second switching tube is an NMOS tube.
In an exemplary embodiment of the present application, the third switching tube is a PMOS tube, and the fourth switching tube is an NMOS tube.
In an exemplary embodiment of the present application, the fifth switching tube is an NMOS tube.
The working principle of the application is analyzed by combining specific embodiments, and compared with the prior art, the application has the following beneficial effects:
1. the parallel circuit can be used for parallel operation of the switching power supply, and parallel redundancy is realized; the switching tubes in the first output control module and the second output control module can be protected from being failed due to huge energy through the short circuit control module, and the switching tube can be particularly used for high-power switching power supplies without constant current function in parallel connection and can be used for most constant voltage products;
2. the parallel circuit can not only carry out 1+1 parallel use on a power supply and avoid damage of short circuit, but also can use fewer driving signals to conduct and turn off a loop through a switching tube self-through self-locking logic;
3. the parallel circuit does not use a digital control chip, so that the complexity of the circuit is reduced, the development cost of a switching power supply is reduced, and the parallel circuit has more advantages in terms of space and cost;
4. the parallel circuit short-circuit protection device can protect a client application load end, a switching power supply end and components and parts from being damaged by stress and heat.
Drawings
Fig. 1 is a schematic circuit diagram of a parallel circuit in a switching power supply of the present application.
Detailed Description
In order to make the technical scheme of the application clearer, the following description of the embodiment of the application is made clearly and completely by combining the drawings. It should be apparent that the embodiments described are some of the embodiments of the present application and that various other modifications, substitutions, or alterations can be made by those skilled in the art without inventive effort, and still fall within the scope of the present application.
Referring to fig. 1, an embodiment of the present application provides a parallel circuit applied to a switching power supply, the parallel circuit including:
the first output control module 100, the first input end of the first output control module 100 is connected to the positive electrode output end of the first switching power supply, the second input end of the first output control module 100 is connected to the negative electrode output end of the first switching power supply, the third input end of the first output control module 100 is connected to the control signal end, and the positive electrode output end of the first output control module 100 is connected to the positive electrode output end of the parallel circuit;
the first input end of the second output control module 200 is connected to the positive electrode output end of the second switching power supply, the second input end of the second output control module 200 is connected to the negative electrode output end of the second switching power supply, the third input end of the second output control module 200 is connected to the control signal end, and the positive electrode output end of the second output control module 200 is connected to the positive electrode output end of the parallel circuit;
the short-circuit control module 300, the input end of the short-circuit control module 300 is connected to the positive electrode output end of the parallel circuit, the output end of the short-circuit control module 300 is connected to the negative electrode output end of the parallel circuit, and the short-circuit control module 300 is also respectively connected to the control signal end, the negative electrode output end of the first output control module 100 and the negative electrode output end of the second output control module 200;
when the load is shorted, the short circuit control module 300 pulls down the voltage of the control signal terminal, so that the first output control module 100 and the second output control module 200 are turned off.
In this embodiment, the control signal GATE at the control signal end needs to provide an initial high level to drive the first output control module 100 and the second output control module 200, and the loop of the parallel circuit is turned on through the "self-on" logic;
when the load is short-circuited, the control signal of the control signal end is used for turning off the first output control module 100 and the second output control module 200, and the loop of the parallel circuit is turned off through the self-locking logic, so that the effect that the current loop generates huge energy after the short circuit is disconnected is achieved.
In an embodiment, the first output control module 100 includes a first resistor R1, a second resistor R2, a first switching tube Q1 and a second switching tube Q2, where a source of the first switching tube Q1 is connected to an anode output end of the first switching power supply, a gate of the first switching tube Q1 is connected to a drain of the second switching tube Q2 through the first resistor R1, a source of the second switching tube Q2 is connected to a cathode output end of the first switching power supply, a gate of the second switching tube Q2 is connected to a control signal end through the second resistor R2, a drain of the first switching tube Q1 is connected to an anode output end of the parallel circuit, and a drain of the second switching tube Q2 is connected to the short circuit control module 300.
The first switching tube Q1 and the second switching tube Q2 may be implemented by using switching devices such as MOS transistors, triodes, and field effect transistors, and in this embodiment, the first switching tube Q1 is a PMOS transistor, and the second switching tube Q2 is an NMOS transistor.
The output current Io flows from VO+ to VO-; the short circuit energy has the following formula: p=i 2*R;
i is short-circuit current, R is impedance of parallel circuit, and is embodied as R of first, second, third, fourth and fifth switching tubes Q1, Q2, Q3, Q4 and Q5 DSON 。
When the first switching power supply and the second switching power supply are in a normal parallel working state, an input voltage V1+ of a positive output end of the first switching power supply is connected with a first switching tube Q1, a first resistor R1 is a driving resistor, an input voltage V1-of a negative output end of the first switching power supply is connected with a second switching tube Q2, the second resistor R2 is a driving resistor, the second switching tube Q2 provides an initial high-level signal by a control signal GATE, and the initial control signal GATE can be sent by a common direct current signal or can be sent by a control IC; the control signal end provides a high level to the grid electrode of the second switching tube Q2, the source electrode of the second switching tube Q2 is connected with V1-to be zero level, and VGS2 of the second switching tube Q2 reaches the conduction threshold voltage conduction; VS2 = vd2 = 0 after turn-on; at this time, the gate of the first switching tube Q1 is connected to the drain of the second switching tube Q2, so that vg1=vd2=vs2=0 in the first switching tube Q1; the first switching tube Q1 is connected with the positive electrode input end V1+, and VS1 is at a high level, and at the moment, VSG1 reaches the conduction threshold voltage to be conducted; the positive electrode output end V1+ and the negative electrode output end V1-of the first switching power supply are conducted, and are output to the positive electrode output end VO+ and the negative electrode output end VO-of the parallel circuit.
In an embodiment, the second output control module 200 includes a third resistor R3, a fourth resistor R4, a third switching tube Q3 and a fourth switching tube Q4, where a source electrode of the third switching tube Q3 is connected to an anode output end of the second switching power supply, a gate electrode of the third switching tube Q3 is connected to a drain electrode of the fourth switching tube Q4 through the third resistor R3, a source electrode of the fourth switching tube Q4 is connected to a cathode output end of the second switching power supply, a gate electrode of the fourth switching tube Q4 is connected to a control signal end through the fourth resistor R4, a drain electrode of the third switching tube Q3 is connected to an anode output end of the parallel circuit, and a drain electrode of the fourth switching tube Q4 is connected to the short circuit control module 300.
The third switching tube Q3 and the fourth switching tube Q4 may be implemented by using switching devices such as MOS tubes, triodes, and field effect tubes, and in this embodiment, the third switching tube Q3 is a PMOS tube, and the fourth switching tube Q4 is an NMOS tube.
The input voltage V < 2+ > of the positive output end of the second switching power supply is connected with a third switching tube Q < 3 >, a third resistor R < 3 > is a driving resistor, the input voltage V < 1 > -of the negative output end of the second switching power supply is connected with a fourth switching tube Q < 4 >, the fourth resistor R < 4 > -is a driving resistor, the fourth switching tube Q < 4 > is provided with an initial high-level signal by a control signal GATE of a control signal end, and the initial control signal GATE can be sent by a common direct current signal or can be sent by a control IC; the control signal GATE provides a high level to the grid electrode of the fourth switching tube Q4, the source electrode of the fourth switching tube Q4 is connected with V2-to be a zero level, and VGS4 of the fourth switching tube Q4 reaches the conduction threshold voltage conduction; VS4 = vd4 = 0 after turn-on; at this time, the gate of the third switching tube Q3 is connected to the drain of the fourth switching tube Q4, so that vg3=vd4=vs4=0 in the third switching tube Q3; the positive electrode input end V < 2+ > and VS < 3+ > of the third switching tube Q3 are connected, and VSG < 3 > reaches the conduction threshold voltage to be conducted at the moment; the positive electrode output end V < 2+ > and the negative electrode output end V < 2 > -of the second switching power supply are conducted, and output to the positive electrode output end VO < + > and the negative electrode output end VO < - > of the parallel circuit.
The positive pole output end V1 < + >, V2 < + > and the negative pole output end V1 < - >, V2 < - >, of the switching power supply are conducted and output in parallel.
In an embodiment, the short-circuit control module 300 includes a fifth resistor R5, a sixth resistor R6, and a fifth switching tube Q5, where a gate of the fifth switching tube Q5 is connected to the control signal end through the sixth resistor R6, a gate of the fifth switching tube Q5 is connected to the positive output end of the parallel circuit through the fifth resistor R5, and a source of the fifth switching tube Q5 is connected to the negative output end of the first output control module 100 and the negative output end of the second output control module 200, respectively, and a drain of the fifth switching tube Q5 is connected to the negative output end of the parallel circuit.
The fifth switching tube Q5 may be implemented by using switching devices such as a MOS tube, a triode, and a field effect tube, and in this embodiment, the fifth switching tube Q5 is an NMOS tube.
The fifth switching tube Q5 of the short-circuit control module 300 is a main control device for realizing short-circuit protection for the whole module; the fifth resistor R5 is a driving resistor, the VO+ voltage drives the fifth switching tubes Q5 and VG5 to be in a high level in a normal parallel loop, VS5 is in a zero level after being connected in parallel, VGS5 reaches a conduction threshold voltage conduction at the moment, and output current Io flows from VO+ to VO-; the switching power supply and the parallel circuit work normally; the parallel effect is achieved; the protection state is not entered.
When the back end load of the client is in an abnormal short circuit state, the potential difference of two ends of the fifth resistor R5 is 0, a zero level is provided to cut off the fifth switching tube Q5, and when the output is in short circuit, the output current Io flows from VO+ to VO-; the voltage of the input end VO+ of the load is pulled to zero voltage by the input ground of the load, the grid voltage of the fifth switch tube Q5 is pulled down to zero voltage instantaneously, and the fifth switch is turned off; at this time, the control signal is connected to vo+ and VO-loops through the sixth resistor R6 and the fifth resistor R5, the control signal is zero, so that the second switching tube Q2 in the first output control module 100 and the fourth switching tube Q4 in the second output control module 200 are turned off, after the second switching tube Q2 and the fourth switching tube Q4 are turned off, vd2=vg1, the second switching tube Q2 is not turned on, and a zero level VG1 cannot be provided, so that VSG1 cannot reach a threshold voltage, and the first switching tube Q1 is turned off; likewise vd4=vg3; the PMOS transistor Q3 is also turned off; the switching tubes of the positive loop and the negative loop are turned off, and the output is turned off, so that the loop realizes a self-locking mode, and the short-circuit protection function is realized, and at the moment, the current loop generates huge energy to be turned off after the short circuit, and the switching tube is turned off so as not to fail.
The foregoing is merely illustrative of the present application and is not to be construed as limiting thereof, and although the present application has been described in detail with reference to examples, it will be apparent to those skilled in the art that modifications and substitutions can be made thereto without departing from the spirit and scope of the application as defined in the appended claims.
Claims (7)
1. A parallel circuit for use in a switching power supply, the parallel circuit comprising:
the first input end of the first output control module is connected to the positive electrode output end of the first switching power supply, the second input end of the first output control module is connected to the negative electrode output end of the first switching power supply, the third input end of the first output control module is connected to the control signal end, and the positive electrode output end of the first output control module is connected to the positive electrode output end of the parallel circuit;
the first input end of the second output control module is connected to the positive electrode output end of the second switching power supply, the second input end of the second output control module is connected to the negative electrode output end of the second switching power supply, the third input end of the second output control module is connected to the control signal end, and the positive electrode output end of the second output control module is connected to the positive electrode output end of the parallel circuit;
the input end of the short circuit control module is connected to the positive electrode output end of the parallel circuit, the output end of the short circuit control module is connected to the negative electrode output end of the parallel circuit, and the short circuit control module is also respectively connected to a control signal end, the negative electrode output end of the first output control module and the negative electrode output end of the second output control module;
when the load is short-circuited, the short-circuit control module pulls down the voltage of the control signal end, so that the first output control module and the second output control module are turned off.
2. A parallel circuit according to claim 1, characterized in that: the first output control module comprises a first resistor, a second resistor, a first switch tube and a second switch tube, wherein a source electrode of the first switch tube is connected to an anode output end of the first switch power supply, a grid electrode of the first switch tube is connected to a drain electrode of the second switch tube through the first resistor, a source electrode of the second switch tube is connected to a cathode output end of the first switch power supply, a grid electrode of the second switch tube is connected to a control signal end through the second resistor, a drain electrode of the first switch tube is connected to an anode output end of the parallel circuit, and a drain electrode of the second switch tube is connected to the short circuit control module.
3. The parallel circuit of claim 1, wherein: the second output control module comprises a third resistor, a fourth resistor, a third switching tube and a fourth switching tube, wherein a source electrode of the third switching tube is connected to an anode output end of the second switching power supply, a grid electrode of the third switching tube is connected to a drain electrode of the fourth switching tube through the third resistor, a source electrode of the fourth switching tube is connected to a cathode output end of the second switching power supply, a grid electrode of the fourth switching tube is connected to a control signal end through the fourth resistor, a drain electrode of the third switching tube is connected to an anode output end of the parallel circuit, and a drain electrode of the fourth switching tube is connected to the short circuit control module.
4. The parallel circuit of claim 1, wherein: the short circuit control module comprises a fifth resistor, a sixth resistor and a fifth switching tube, wherein a grid electrode of the fifth switching tube is connected to a control signal end through the sixth resistor, the grid electrode of the fifth switching tube is connected to a positive electrode output end of the parallel circuit through the fifth resistor, a source electrode of the fifth switching tube is respectively connected with a negative electrode output end of the first output control module and a negative electrode output end of the second output control module, and a drain electrode of the fifth switching tube is connected to a negative electrode output end of the parallel circuit.
5. A parallel circuit according to claim 2, characterized in that: the first switching tube is a PMOS tube, and the second switching tube is an NMOS tube.
6. A parallel circuit according to claim 3, characterized in that: the third switching tube is a PMOS tube, and the fourth switching tube is an NMOS tube.
7. A parallel circuit according to claim 4, wherein: the fifth switching tube is an NMOS tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310796423.8A CN116827084A (en) | 2023-06-29 | 2023-06-29 | Parallel circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310796423.8A CN116827084A (en) | 2023-06-29 | 2023-06-29 | Parallel circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116827084A true CN116827084A (en) | 2023-09-29 |
Family
ID=88116334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310796423.8A Pending CN116827084A (en) | 2023-06-29 | 2023-06-29 | Parallel circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116827084A (en) |
-
2023
- 2023-06-29 CN CN202310796423.8A patent/CN116827084A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR900006046B1 (en) | An overcurrent protective circuit for modulated-conductivity type mosfet | |
| EP2706639B1 (en) | Surge protection circuit | |
| JP5266029B2 (en) | Load drive device | |
| CN213846230U (en) | Overcurrent protection circuit | |
| US20050110556A1 (en) | Bootstrap driver | |
| CN113676029A (en) | Active clamping circuit based on IGBT | |
| CN106953627B (en) | Grid driving circuit of power device | |
| CN216086603U (en) | Inductive load switch tube protection circuit | |
| CN114915145A (en) | Soft turn-off circuit and method of SiC MOSFET | |
| CN112332821B (en) | MOSFET passive isolation anti-through fast-closing driving circuit | |
| US20130328537A1 (en) | Buck converter with reverse current protection, and a photovoltaic system | |
| CN110798199B (en) | MOS tube driving circuit | |
| CN116827084A (en) | Parallel circuit | |
| CN114337339B (en) | Rectifier bridge driving circuit with port short circuit detection | |
| CN212304777U (en) | Single-circuit battery discharge circuit | |
| CN110176856B (en) | Zero-quiescent-current power switch circuit with overcurrent protection and implementation method | |
| JP2001177387A (en) | Load driver | |
| CN204668926U (en) | A kind of IGBT drives and protective circuit | |
| CN113437726A (en) | Reverse-connection-preventing self-recovery overcurrent protection circuit | |
| CN112510672A (en) | Reverse connection prevention follow current protection circuit and terminal | |
| CN218771305U (en) | Anti-reverse connection circuit with overvoltage protection function | |
| CN111082788B (en) | Gate driving device and electronic equipment | |
| CN117240277B (en) | Substrate selection circuit and electronic equipment | |
| CN115395495B (en) | Overvoltage protection circuit | |
| CN215581093U (en) | Push-pull type driving device |
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 |