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CN-224204989-U - Switching power supply starting protection circuit

CN224204989UCN 224204989 UCN224204989 UCN 224204989UCN-224204989-U

Abstract

The utility model discloses a switch power supply starting protection circuit, which relates to the technical field of switch power supplies and comprises an input detection module, wherein before starting, the input detection module is matched with a state detection module to calculate the electric energy difference value input into the power supply module and output from the power supply module, a voltage comparison module is used for judging whether the power supply module normally carries out electric energy processing or not by comparing the detected electric energy difference value with the voltage relation of a set voltage threshold value, and when the power supply module is normal, a starting control module is used for carrying out electric energy transmission and high-frequency adjustment processing by a high-frequency output module to control the input detection module and the state detection module to stop detection work. The switch power supply starting protection circuit can improve starting safety and reduce the influence of the voltage detection part on electric energy.

Inventors

  • Feng Linzhou

Assignees

  • 深圳初心始终技术有限公司

Dates

Publication Date
20260505
Application Date
20250604

Claims (6)

  1. 1. A switch power supply start-up protection circuit is characterized in that, The switch power supply starting protection circuit comprises a power supply module, an input detection module, a state detection module, a voltage comparison module, a self-locking module, a starting control module and a high-frequency output module; The power module is used for carrying out transformation, rectification and filtering treatment on the accessed alternating current electric energy and outputting first electric energy; The input detection module is connected with the power supply module and used for reducing voltage, rectifying and sampling partial voltage of the alternating current power and outputting a first detection signal; The state detection module is connected with the power supply module and the input detection module and is used for receiving the first electric energy, dividing and sampling the first electric energy, calculating the voltage difference value between the first detection signal and the sampled signal and outputting a second detection signal; The voltage comparison module is connected with the state detection module and is used for outputting a first starting signal when the second detection signal is larger than a set second voltage threshold value and smaller than a set first voltage threshold value; the self-locking module is connected with the voltage comparison module, the input detection module, the power supply module and the state detection module and is used for receiving the first electric energy, performing self-locking processing on the first starting signal, outputting the second starting signal, controlling the state detection module to stop receiving the first electric energy and controlling the input detection module to stop working; the starting control module is connected with the power supply module, the high-frequency output module and the self-locking module and is used for transmitting the first electric energy to the high-frequency output module when receiving the second starting signal; and the high-frequency output module is used for carrying out overvoltage protection and high-frequency voltage stabilization regulation on the input first electric energy and outputting the first electric energy.
  2. 2. The switching power supply start-up protection circuit according to claim 1, wherein the power supply module comprises a power supply interface, an electric energy regulating device and a first capacitor, the start-up control module comprises an eighth resistor, a second power tube and a third switching tube, and the high-frequency output module comprises a second capacitor, a tenth resistor, a third diode, a ninth resistor, a second diode, a first transformer, the power regulating device, a fourth diode and an output port; The first end and the second end of the power interface are respectively connected with the first end and the second end of the power regulating device, the third end of the power regulating device is connected with one end of the first capacitor and the source electrode of the second power tube and is connected with the grid electrode of the second power tube and the collector electrode of the third switching tube through the eighth resistor, the emitter electrode of the third switching tube is connected with the other end of the first capacitor, the fourth end of the power regulating device, the grounding end and the ground end of the power regulating device, the drain electrode of the second power tube is connected with one end of the second capacitor and the first end of the primary side of the first transformer and is connected with the other end of the second capacitor through the tenth resistor, the cathode of the third diode and the one end of the ninth resistor, the other end of the ninth resistor is connected with the cathode of the second diode, the anode of the third diode is connected with the second end of the primary side of the first transformer and the control end of the power regulating device, the first end of the secondary side of the first transformer is connected with the anode of the fourth diode, the cathode of the fourth diode is connected with the feedback end of the power regulating device and one end of the output port, and the other end of the secondary side of the first transformer is connected with the output port.
  3. 3. The switching power supply start-up protection circuit of claim 2, wherein the input detection module comprises a first relay switch, a first resistor, a third capacitor, a first rectifier, a second resistor, and a third resistor; The first static end and the second static end of the first relay switch are respectively connected with the first end and the second end of the power interface, the first movable end of the first relay switch is connected with one end of the third capacitor and is connected with the other end of the third capacitor and the second end of the first rectifier through the first resistor, the second movable end of the first relay switch is connected with the first end of the first rectifier, the third end of the first rectifier is connected with the first end of the third resistor through the second resistor, and the second end of the third resistor is connected with the fourth end of the first rectifier and the ground end.
  4. 4. A switching power supply start-up protection circuit according to claim 3, wherein the state detection module comprises a fourth resistor, a fifth resistor, a subtracting device, a first power tube, a sixth resistor and a first switching tube; One end of the fourth resistor is connected with the drain electrode of the first power tube and the third end of the electric energy regulating device and is connected with the grid electrode of the first power tube and the collector electrode of the first switching tube through the sixth resistor, the other end of the fourth resistor is connected with the second input end of the subtracting device and is connected with the emitter electrode of the first switching tube and the ground end through the fifth resistor, the first input end of the subtracting device is connected with the first end of the third resistor, the power end of the subtracting device is connected with the source electrode of the first power tube, and the output end of the subtracting device is connected with the voltage comparing module.
  5. 5. The switching power supply start-up protection circuit according to claim 4, wherein the self-locking module comprises a seventh resistor, a first diode and a first logic chip; The end B of the first logic chip is connected with one end of the first relay and the third end of the electric energy regulating device through a seventh resistor, the other end of the first relay is connected with the collector electrode of the second switching tube, the emitter electrode of the second switching tube is grounded, the base electrode of the second switching tube is connected with the end Y of the first logic chip, the base electrode of the third switching tube, the anode of the first diode and the base electrode of the first switching tube, and the end A of the first logic chip is connected with the cathode of the first diode and the voltage comparison module.
  6. 6. The switching power supply start-up protection circuit of claim 5, wherein the voltage comparison module comprises a first comparator, a second comparator, a first reference power supply, a second reference power supply, and a second logic chip; The inverting terminal of the first comparator is connected with the in-phase terminal of the second comparator and the output terminal of the subtracting device, the in-phase terminal of the first comparator and the inverting terminal of the second comparator are respectively connected with a first reference power supply and a second reference power supply, the output terminal of the first comparator and the output terminal of the second comparator are respectively connected with the A terminal and the B terminal of the second logic chip, and the Y terminal of the second logic chip is connected with the A terminal of the first logic chip.

Description

Switching power supply starting protection circuit Technical Field The utility model relates to the technical field of switching power supplies, in particular to a switching power supply starting protection circuit. Background The switching power supply is composed of an input rectifying and filtering circuit, a power conversion circuit, an output rectifying and filtering circuit and a control circuit, realizes high-frequency voltage stabilizing adjustment, and in the prior art, in order to avoid the overcurrent condition during starting, current-limiting starting control is carried out on the electric energy output by the input rectifying and filtering circuit, however, before the switching power supply is started, it cannot be known whether the power is abnormal or not, and the starting power is easy to cause abnormal conditions, so that the safety of the circuit is reduced, and therefore, the improvement is needed. Disclosure of utility model The embodiment of the utility model provides a switch power supply starting protection circuit to solve the problems in the background technology. In order to achieve the above purpose, the present utility model provides the following technical solutions: the switch power supply starting protection circuit comprises a power supply module, an input detection module, a state detection module, a voltage comparison module, a self-locking module, a starting control module and a high-frequency output module; The power module is used for carrying out transformation, rectification and filtering treatment on the accessed alternating current electric energy and outputting first electric energy; The input detection module is connected with the power supply module and used for reducing voltage, rectifying and sampling partial voltage of the alternating current power and outputting a first detection signal; The state detection module is connected with the power supply module and the input detection module and is used for receiving the first electric energy, dividing and sampling the first electric energy, calculating the voltage difference value between the first detection signal and the sampled signal and outputting a second detection signal; The voltage comparison module is connected with the state detection module and is used for outputting a first starting signal when the second detection signal is larger than a set second voltage threshold value and smaller than a set first voltage threshold value; the self-locking module is connected with the voltage comparison module, the input detection module, the power supply module and the state detection module and is used for receiving the first electric energy, performing self-locking processing on the first starting signal, outputting the second starting signal, controlling the state detection module to stop receiving the first electric energy and controlling the input detection module to stop working; the starting control module is connected with the power supply module, the high-frequency output module and the self-locking module and is used for transmitting the first electric energy to the high-frequency output module when receiving the second starting signal; and the high-frequency output module is used for carrying out overvoltage protection and high-frequency voltage stabilization regulation on the input first electric energy and outputting the first electric energy. The high-frequency output module comprises a second capacitor, a tenth resistor, a third diode, a ninth resistor, a second diode, a first transformer, a power regulating device, a fourth diode and an output port; Preferably, the first end and the second end of the power interface are respectively connected with the first end and the second end of the power regulating device, the third end of the power regulating device is connected with one end of the first capacitor and the source electrode of the second power tube and is connected with the grid electrode of the second power tube and the collector electrode of the third switching tube through the eighth resistor, the emitter electrode of the third switching tube is connected with the other end of the first capacitor, the fourth end of the power regulating device, the grounding end and the ground end of the power regulating device, the drain electrode of the second power tube is connected with one end of the second capacitor and the first end of the primary side of the first transformer and is connected with the other end of the second capacitor through the tenth resistor, the cathode of the third diode and one end of the ninth resistor, the other end of the ninth resistor is connected with the cathode of the second diode, the anode of the third diode is connected with the second end of the primary side of the first transformer and the control end of the power regulating device, the first end of the secondary side of the first transformer is connected with the anode of the fourth diode, the cathode of the fourth