CN108322053B - Step-down conversion circuit - Google Patents
Step-down conversion circuit Download PDFInfo
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- CN108322053B CN108322053B CN201810052277.7A CN201810052277A CN108322053B CN 108322053 B CN108322053 B CN 108322053B CN 201810052277 A CN201810052277 A CN 201810052277A CN 108322053 B CN108322053 B CN 108322053B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
Abstract
The invention discloses a step-down conversion circuit which is used for supplying power to a control circuit and comprises a main switching tube, a switching tube and a transformer; the input end of the main switching tube is connected with a working pulse signal, so that the main switching tube is switched from off to on; the output end of the main switching tube is connected with the transformer to start the transformer; the input end of the switching tube is connected with a narrow pulse signal when the circuit is in light load, so that the switching tube is switched from off to on; the output end of the switch tube is connected with the transformer, so that the reflected voltage of the transformer is forced to reach the output voltage, and a stable auxiliary power supply is provided. The invention can provide a stable auxiliary power supply to supply power for a control circuit and the like when the circuit is lightly loaded.
Description
Technical Field
The invention relates to the technical field of electronics, in particular to a buck conversion circuit.
Background
In order to work reliably, the BUCK-type BUCK circuit with higher working voltage needs to use an additional auxiliary power supply to supply power to the drive circuit and the control circuit of the high-side field effect transistor respectively. In order to simplify the circuit and reduce the cost, the power-on starting can be realized by using the starting resistor, and the auxiliary winding on the output inductor is used for continuously supplying power.
However, in the conventional step-down circuit, when the output is no-load (almost only the sampling resistor of the voltage feedback is used as a load), the duty ratio of the operation is extremely small, and the current of the transformer is also small. After the circuit is switched from on to off, the transformer continues current, and the parasitic capacitor is charged by the current of the transformer, so that the reflected voltage of the transformer can not reach the output voltage. The rectified voltage of each auxiliary winding, which is proportional to the voltage, is also low, so that the control circuit and the driving circuit cannot maintain normal operation.
Disclosure of Invention
The invention provides a buck conversion circuit aiming at the problems in the prior art, which can provide a stable auxiliary power supply for supplying power to a control circuit and the like when the circuit is in light load.
The technical scheme provided by the invention for the technical problem is as follows:
on one hand, the invention provides a buck conversion circuit which is used for supplying power to a control circuit and comprises a main switching tube, a switching tube and a transformer;
the input end of the main switching tube is connected with a working pulse signal, so that the main switching tube is switched from off to on; the output end of the main switching tube is connected with the transformer to start the transformer;
the input end of the switching tube is connected with a narrow pulse signal when the circuit is in light load, so that the switching tube is switched from off to on; the output end of the switch tube is connected with the transformer, so that the reflected voltage of the transformer is forced to reach the output voltage, and a stable auxiliary power supply is provided.
Furthermore, the access time of the narrow pulse signal is separated from the access time of the working pulse signal by a dead time;
after the main switching tube is switched in the working pulse signal and is switched on, the current of the transformer rises to the maximum value, and the main switching tube is cut off; the current of the transformer decreases linearly within the dead time; after the dead-time is over, the switch tube is switched in the narrow pulse signal to be conducted, the current of the transformer gradually decreases to 0 and then reversely rises to a maximum value, and the switch tube is cut off; the current of the transformer is freewheeling by the reverse current until the reverse current drops to 0.
Further, the duration of the narrow pulse signal is t3, the inductance of the transformer is L, and the output voltage is UOThe reverse maximum value of the transformer current is
So that the reflected voltage of the transformer reaches the output voltage to provide a stable auxiliary power supply.
Further, the circuit also includes an output capacitor;
the output capacitor is connected with the transformer and used for charging through the current of the transformer in the periodic conduction process of the switching tube and loading the stored voltage onto the transformer to maintain the circuit to work when the input is powered off.
Further, the circuit further comprises an input capacitance;
the input capacitor is connected with the transformer and used for charging through the current of the transformer in the periodic conduction process of the main switching tube and loading the stored voltage onto the transformer when the input is powered off so as to maintain the circuit to work.
Further, the main switch tube and the switch tube are both field effect tubes.
Further, the circuit further comprises a first diode, a second diode, a third diode, a first isolation driver and a second isolation driver; the transformer comprises a primary winding, a first secondary winding and a second secondary winding;
the drain electrode of the main switching tube is connected with the positive electrode of a power supply, the source electrode of the main switching tube is respectively connected with the homonymous end of the primary winding of the transformer, the homonymous end of the first secondary winding, the third end of the first isolation driver, the negative electrode of the first diode and the drain electrode of the switching tube, the grid electrode of the main switching tube is connected with the first end of the first isolation driver, the second end of the first isolation driver is connected with the negative electrode of the third diode, the positive electrode of the third diode is connected with the synonym end of the first secondary winding of the transformer, and the fourth end of the first isolation driver is connected with the control circuit;
the source electrode of the switch tube, the anode of the first diode, the third end of the second isolation driver and the homonymous end of the second secondary winding of the transformer are respectively connected with the cathode of a power supply, the grid electrode of the switch tube is connected with the first end of the second isolation driver, the second end of the second isolation driver is respectively connected with the cathode of the second diode and the control circuit, the fourth end of the second isolation driver is connected with the control circuit, and the anode of the second diode is connected with the heteronymous end of the second secondary winding of the transformer;
one end of the input capacitor is connected with the positive electrode of the power supply, and the other end of the input capacitor is connected with the negative electrode of the power supply; one end of the output capacitor is connected with the synonym end of the primary winding of the transformer, and the other end of the output capacitor is connected with the negative electrode of the power supply.
Further, the circuit further comprises a first capacitor, a second capacitor, a first resistor, a second resistor, a load resistor, a sensor and a voltage sensor;
one end of the first capacitor is connected with the negative electrode of the third diode, and the other end of the first capacitor is connected with the source electrode of the main switching tube; one end of the second capacitor is connected with the cathode of the second diode, and the other end of the second capacitor is connected with the cathode of the power supply; one end of the first resistor and one end of the second resistor are respectively connected with the anode of a power supply, and the other end of the first resistor is connected with the cathode of the second diode; the other end of the second resistor is connected with the cathode of the third diode;
the first end of the sensor is connected with the synonym end of the primary winding of the transformer, the second end of the sensor is connected with the control circuit, and the third end of the sensor is respectively connected with the second end of the voltage sensor, one end of the output capacitor and one end of the load resistor; the third end of the voltage sensor and the other end of the load resistor are respectively connected with the negative electrode of the power supply, and the first end of the voltage sensor is connected with the control circuit. The technical scheme provided by the embodiment of the invention has the following beneficial effects:
the circuit is additionally provided with a switching tube, when the circuit is in light load, a narrow pulse signal is additionally connected to conduct the switching tube, the reflected voltage of the transformer is forced to be equal to the output voltage, each auxiliary winding can output proportional voltage, and stable direct-current voltage is provided for a control circuit and a driving circuit, so that the problems of light load and no load are perfectly solved, an additional auxiliary power supply is not needed, the cost is low, the circuit is simplified, and the reliability is high; the working pulse signal and the narrow pulse signal are input, so that the transformer has only low-current reverse excitation when the circuit is in light load, and the standby power consumption of the whole circuit is low; the energy stored by the output capacitor can also be used to maintain the power output of the transformer windings.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a buck conversion circuit according to a first embodiment of the present invention;
fig. 2 is a waveform diagram of a working pulse signal before and a narrow pulse signal after when the buck converter circuit according to the first embodiment of the present invention is in light load;
fig. 3 is a waveform diagram of the narrow pulse signal before and the working pulse signal after the buck converter circuit according to the first embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
Example one
The embodiment of the invention provides a buck conversion circuit, which is shown in fig. 1 and is used for supplying power to a control circuit 1, and comprises a main switching tube Q1, a switching tube Q2 and a transformer T1;
the input end of the main switching tube Q1 is connected with a working pulse signal, so that the main switching tube Q1 is switched from off to on; the output end of the main switching tube Q1 is connected with the transformer T1 to start the transformer T1;
the input end of the switching tube Q2 is connected with a narrow pulse signal when the circuit is in light load, so that the switching tube Q2 is switched from off to on; the output terminal of the switching tube Q2 is connected to the transformer T1, and the reflected voltage of the transformer T1 is forced to reach the output voltage, so as to provide a stable auxiliary power source.
The switch tube Q2 is a low power switch tube, and its capacity is 1/2-1/4 of the capacity of the main switch tube Q1. The main switch tube Q1 and the switch tube Q2 are connected to the pulse signal through a controller (not shown in the figure).
When the circuit is lightly loaded, the controller additionally outputs a narrow pulse to the switching tube Q2 to turn on the switching tube Q2, so that the reflected voltage of the transformer T1 is forced to be equal to the output voltage, and each auxiliary winding of the transformer T1 can output a proportional voltage, thereby providing a stable direct current voltage for the control circuit, the driving circuit and the like.
Furthermore, the access time of the narrow pulse signal is separated from the access time of the working pulse signal by a dead time;
after the main switching tube is switched in the working pulse signal and is switched on, the current of the transformer rises to the maximum value, and the main switching tube is cut off; the current of the transformer decreases linearly within the dead time; after the dead-time is over, the switch tube is switched in the narrow pulse signal to be conducted, the current of the transformer gradually decreases to 0 and then reversely rises to a maximum value, and the switch tube is cut off; the current of the transformer is freewheeling by the reverse current until the reverse current drops to 0.
It should be noted that the controller is basically the same as the loop of the conventional current mode or voltage mode PWM controller, except that the wave-making mode is different, and a narrow pulse signal needs to be added before the rising edge or after the falling edge of each working pulse signal, and a reasonable dead zone is maintained with the original working pulse signal.
Fig. 2 shows the operation waveforms of the operation pulse signal VH preceding and the narrow pulse signal VL succeeding when the circuit is lightly loaded. In each switching cycle of the switching tube, the circuit has 4 states: the controller outputs a working pulse signal, the main switching tube Q1 is switched on, the current of the transformer T1 rises to reach the maximum value, and then the main switching tube Q1 is switched off, wherein the duration time of the main switching tube Q1 is T1; to prevent shoot-through, a dead time is set, during which the current of the transformer T1 drops linearly, where the dead time is T2; after the dead time is over, the switching tube Q2 drives a pulse (the width is about 500ns), at this time, the current of the transformer T1 continuously decreases to 0, then reversely increases to the maximum value, the switching tube Q2 is turned off, and the conduction time of the switching tube Q2 is T3; the transformer T1 is in a freewheeling state and current freewheels from the reverse current and gradually drops to 0, where the freewheeling state of the transformer T1 lasts for a time T4. During the time that the current of the transformer T1 drops to 0 until the next switching cycle, the main switch Q1 and the switch Q2 are both in the off state.
The working waveforms of the circuit with the narrow pulse signal VL in front and the working pulse signal VH in back are shown in fig. 3, and the working mode is substantially the same as the working mode with the working pulse signal VH in front and the narrow pulse signal VL in back, which is not described in detail again.
Further, the duration of the narrow pulse signal is t3, the inductance of the transformer is L, and the output voltage is UOThe reverse maximum value of the transformer current is
So that the reflected voltage of the transformer reaches the output voltage to provide a stable auxiliary power supply.
After the time lengths of t2 and t3 are set, the times of t1 and t4 are determined by the input/output voltage. I in the present examplepkCompared with the no-load condition when the switch tube Q2 is not added in the prior art, the no-load condition is much larger and is about 2.5% of the full load, the switch tube Q2 can be turned on hard, and the voltage at two ends of the transformer T1 is forced to reach the output voltage, so that all auxiliary windings of the transformer T1 can be rectified to obtain electricity.
Further, the circuit also includes an output capacitor C1;
the output capacitor C1 is connected to the transformer T1, and is used for charging the current passing through the transformer T1 during the periodic conduction of the switching tube, and loading the stored voltage to the transformer T1 when the input is powered off, so as to maintain the circuit operation.
Further, the circuit also includes an input capacitance C2;
the input capacitor C2 is connected to the transformer T1, and is used for charging the current passing through the transformer T1 during the periodic conduction of the main switching tube, and loading the stored voltage to the transformer T1 when the input is powered off, so as to maintain the circuit operation.
When the input capacitor C2 or the output capacitor C1 stores energy, the switching tube Q2 is turned on periodically to transfer the stored energy to the input terminal, so as to maintain the power supply of each winding of the transformer T1 and keep the circuit operating.
Further, the main switch tube Q1 and the switch tube Q2 are both field effect transistors.
The switching tube Q2 may also be formed by an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) (the MOSFET is preferably connected in series with a low-voltage schottky diode).
Further, the circuit also includes a first diode D1, a second diode D2, a third diode D3, a first isolation driver U1, and a second isolation driver U2; the transformer T1 comprises a primary winding L1, a first secondary winding L2 and a second secondary winding L3;
a drain of the main switching tube Q1 is connected to an anode of a power supply V, a source of the main switching tube Q1 is connected to a dotted end of a primary winding L1 of the transformer T1, a dotted end of the first secondary winding L2, a third end of the first isolation driver U1, a cathode of the first diode D1, and a drain of the switching tube Q2, a gate of the main switching tube Q1 is connected to a first end of the first isolation driver U1, a second end of the first isolation driver U1 is connected to a cathode of the third diode D3, an anode of the third diode D3 is connected to a different-name end of a second secondary winding L2 of the transformer T1, and a fourth end of the first isolation driver U1 is connected to the control circuit 1;
a source of the switching tube Q2, an anode of the first diode D1, a third end of the second isolation driver U2, and a dotted end of the second secondary winding L3 of the transformer T1 are respectively connected to a negative electrode of a power supply V, a gate of the switching tube Q2 is connected to a first end of the second isolation driver U2, a second end of the second isolation driver U2 is respectively connected to a negative electrode of the second diode D2 and the control circuit 1, a fourth end of the second isolation driver U2 is connected to the control circuit 1, and an anode of the second diode D2 is connected to a dotted end of the second secondary winding L3 of the transformer T1;
one end of the input capacitor C2 is connected with the positive pole of a power supply V, and the other end of the input capacitor C2 is connected with the negative pole of the power supply V; one end of the output capacitor C1 is connected with the synonym end of the primary winding L1 of the transformer T1, and the other end of the output capacitor C1 is connected with the negative electrode of the power supply V.
Further, the circuit further comprises a first capacitor C3, a second capacitor C4, a first resistor Rboot1, a second resistor Rboot2, a load resistor R1, a sensor ISEN1 and a voltage sensor VSEN 1;
one end of the first capacitor C3 is connected to the cathode of the third diode D3, and the other end of the first capacitor C3 is connected to the source of the main switch Q1; one end of the second capacitor C4 is connected with the cathode of the second diode D2, and the other end of the second capacitor C4 is connected with the cathode of the power supply V; one end of the first resistor Rboot1 and one end of the second resistor Rboot2 are respectively connected with the positive electrode of a power supply V, and the other end of the first resistor Rboot1 is connected with the negative electrode of the second diode D2; the other end of the second resistor Rboot2 is connected with the cathode of the third diode D3;
a first end of the sensor ISEN1 is connected with a synonym end of a primary winding L1 of the transformer T1, a second end of the sensor ISEN1 is connected with the control circuit 1, and a third end of the sensor ISEN1 is respectively connected with a second end of the voltage sensor VSEN1, one end of the output capacitor C1 and one end of the load resistor R1; the third end of the voltage sensor VSEN1 and the other end of the load resistor R1 are respectively connected with a power supply V negative pole, and the first end of the voltage sensor VSEN1 is connected with the control circuit 1.
In addition, when the circuit is lightly loaded, the switching tube Q2 has a certain on-off loss, which depends on the length of t 3. When T3 is longer, I of transformer T1pkThe parasitic capacitance C2 of the main switch Q1, the switch Q2 and the first diode D1 is relatively large enough to charge the main switch Q1, the switch Q2 and the first diode D1 in the dead time, and the Q2 can realize soft turn-on but has turn-off loss. I of transformer T1 when T3 is shortpkAnd the voltage is also small and is not enough to charge the parasitic capacitor C2, and the switch tube Q2 realizes partial soft switching-on and partial switching-on loss and simultaneous switching-off loss. The pulse width of the Q2 is very short, so that the control loop of the circuit is not affected basically, and the peak value of the current of the transformer T1 is small, so that the magnetic core is formedThe losses are also extremely low.
When the effective duty ratio is larger than the duty ratio determined by t2 when the load is fully loaded or slightly loaded, the switch tube Q2 will be turned on softly, and when the switch tube Q2 is turned off, the first diode D1 will remain on without the end of the follow current, and there is no turn-off loss, which is completely consistent with the operating condition without Q2.
The embodiment of the invention can add the switch tube in the circuit, when the circuit is in light load, a narrow pulse signal is additionally connected to conduct the switch tube, the reflected voltage of the transformer is forced to be equal to the output voltage, each auxiliary winding can output proportional voltage, and stable direct current voltage is provided for the control circuit and the driving circuit, so that the problems of light load and no load are perfectly solved, no additional auxiliary power supply is needed, no dummy load is needed, the cost is low, the circuit is simplified, the reliability is high, the output voltage is stable, the circuit has certain load (the control circuit and the driving circuit) capacity, and the relation with the load is not large; the working current of the switching tube is small, and for the condition of a slightly large load, the switching tube can realize ZVS (Zero Voltage Switch) and ZCS (Zero Current Switch) without influencing the main circuit; the input mode of the working pulse signal and the narrow pulse signal ensures that the transformer has only reverse excitation of small current when the circuit is in light load, and the standby power consumption of the whole circuit is low (for example, a 2kW circuit inputs 310Vdc and outputs 120Vdc, and the actual measurement of the standby power consumption is only-3W); the energy stored by the output capacitor can also be used to maintain the power output of the transformer windings.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (4)
1. A step-down conversion circuit is used for supplying power to a control circuit and is characterized by comprising a main switching tube, a switching tube and a transformer;
the input end of the main switching tube is connected with a working pulse signal, so that the main switching tube is switched from off to on; the output end of the main switching tube is connected with the transformer to start the transformer;
the input end of the switching tube is connected with a narrow pulse signal when the circuit is in light load, so that the switching tube is switched from off to on; the output end of the switching tube is connected with the transformer, so that the reflected voltage of the transformer is forced to reach the output voltage, and a stable auxiliary power supply is provided;
the access time of the narrow pulse signal and the access time of the working pulse signal are separated by a dead time;
after the main switching tube is switched in the working pulse signal and is switched on, the current of the transformer rises to the maximum value, and the main switching tube is cut off; the current of the transformer decreases linearly within the dead time; after the dead time is over, the switch tube is connected into the narrow pulse signal to be conducted, the current of the transformer gradually decreases to 0 and then reversely increases to a maximum value, and the switch tube is cut off; the current of the transformer is continued by reverse current until the reverse current is reduced to 0;
the circuit further comprises an input capacitance;
the input capacitor is connected with the transformer and used for charging through the current of the transformer in the periodic conduction process of the main switching tube and loading the stored voltage onto the transformer to maintain the circuit to work when the input is powered off;
the main switching tube and the switching tube are both field effect tubes;
the circuit further comprises a first diode, a second diode, a third diode, a first isolation driver and a second isolation driver; the transformer comprises a primary winding, a first secondary winding and a second secondary winding;
the drain electrode of the main switching tube is connected with the positive electrode of a power supply, the source electrode of the main switching tube is respectively connected with the homonymous end of the primary winding of the transformer, the homonymous end of the first secondary winding, the third end of the first isolation driver, the negative electrode of the first diode and the drain electrode of the switching tube, the grid electrode of the main switching tube is connected with the first end of the first isolation driver, the second end of the first isolation driver is connected with the negative electrode of the third diode, the positive electrode of the third diode is connected with the synonym end of the first secondary winding of the transformer, and the fourth end of the first isolation driver is connected with the control circuit;
the source electrode of the switch tube, the anode of the first diode, the third end of the second isolation driver and the homonymous end of the second secondary winding of the transformer are respectively connected with the cathode of a power supply, the grid electrode of the switch tube is connected with the first end of the second isolation driver, the second end of the second isolation driver is respectively connected with the cathode of the second diode and the control circuit, the fourth end of the second isolation driver is connected with the control circuit, and the anode of the second diode is connected with the heteronymous end of the second secondary winding of the transformer;
one end of the input capacitor is connected with the positive electrode of the power supply, and the other end of the input capacitor is connected with the negative electrode of the power supply; one end of the output capacitor is connected with the synonym end of the primary winding of the transformer, and the other end of the output capacitor is connected with the negative electrode of the power supply.
2. The buck converter circuit according to claim 1, wherein the narrow pulse signal has a duration of t3, the transformer has an inductance of L, and the output voltage is UOThe reverse maximum value of the transformer current is
So that the reflected voltage of the transformer reaches the output voltage to provide a stable auxiliary power supply.
3. The buck conversion circuit according to claim 1, wherein the circuit further comprises an output capacitor;
the output capacitor is connected with the transformer and used for charging through the current of the transformer in the periodic conduction process of the switching tube and loading the stored voltage onto the transformer to maintain the circuit to work when the input is powered off.
4. The buck conversion circuit according to claim 1, wherein the circuit further comprises a first capacitor, a second capacitor, a first resistor, a second resistor, a load resistor, a sensor, and a voltage sensor;
one end of the first capacitor is connected with the negative electrode of the third diode, and the other end of the first capacitor is connected with the source electrode of the main switching tube; one end of the second capacitor is connected with the cathode of the second diode, and the other end of the second capacitor is connected with the cathode of the power supply; one end of the first resistor and one end of the second resistor are respectively connected with the anode of a power supply, and the other end of the first resistor is connected with the cathode of the second diode; the other end of the second resistor is connected with the cathode of the third diode;
the first end of the sensor is connected with the synonym end of the primary winding of the transformer, the second end of the sensor is connected with the control circuit, and the third end of the sensor is respectively connected with the second end of the voltage sensor, one end of the output capacitor and one end of the load resistor; the third end of the voltage sensor and the other end of the load resistor are respectively connected with the negative electrode of the power supply, and the first end of the voltage sensor is connected with the control circuit.
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| CN201810052277.7A CN108322053B (en) | 2018-01-19 | 2018-01-19 | Step-down conversion circuit |
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| CN201810052277.7A CN108322053B (en) | 2018-01-19 | 2018-01-19 | Step-down conversion circuit |
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| CN108322053B true CN108322053B (en) | 2020-10-09 |
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| CN115603570A (en) * | 2021-06-28 | 2023-01-13 | 碇基半导体股份有限公司（Tw） | Switching circuit |
| CN115864858B (en) * | 2023-03-01 | 2023-05-05 | 恩赛半导体(成都)有限公司 | Auxiliary power supply, power supply system and electronic device |
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| CN101197540A (en) * | 2007-12-11 | 2008-06-11 | 艾默生网络能源有限公司 | Dc converter |
| CN105915063A (en) * | 2016-05-18 | 2016-08-31 | 南京理工大学 | Synchronous step-down topological circuit with isolated output |
| CN106469983A (en) * | 2015-08-14 | 2017-03-01 | 艾默生网络能源有限公司 | A kind of auxiliary power circuit |
| CN107408889A (en) * | 2015-03-03 | 2017-11-28 | 三菱电机株式会社 | Power converter |
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2018
- 2018-01-19 CN CN201810052277.7A patent/CN108322053B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101197540A (en) * | 2007-12-11 | 2008-06-11 | 艾默生网络能源有限公司 | Dc converter |
| CN107408889A (en) * | 2015-03-03 | 2017-11-28 | 三菱电机株式会社 | Power converter |
| CN106469983A (en) * | 2015-08-14 | 2017-03-01 | 艾默生网络能源有限公司 | A kind of auxiliary power circuit |
| CN105915063A (en) * | 2016-05-18 | 2016-08-31 | 南京理工大学 | Synchronous step-down topological circuit with isolated output |
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