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CN-224218276-U - Double-tube flyback switching power supply

CN224218276UCN 224218276 UCN224218276 UCN 224218276UCN-224218276-U

Abstract

The utility model relates to the technical field of switching power supplies, in particular to a double-tube flyback switching power supply, wherein a PFC module is composed of a PFC chip U1 and peripheral circuits thereof, the peripheral circuits of the PFC chip U1 are provided with quick starting circuits, the quick starting circuits are integrally packaged in the PFC chip U1, an auxiliary driving module is composed of a double-tube driving chip U2 and peripheral circuits thereof, the double-tube circuits are integrally packaged in the double-tube driving chip U2, a main driving module is composed of a single-tube driving chip U3 and peripheral circuits thereof, the single-tube driving chip U3 is additionally provided with a switching signal end, the switching signal end is electrically connected with the input end of the double-tube driving chip U2, and the problems that single-chip driving double-tube control is difficult, multiple peripheral circuit discrete elements of multiple chips occupy circuit board space and production efficiency is low in the switching power supply are solved.

Inventors

  • ZHAO NANNAN
  • XU WEI
  • CHEN LIANGHUI

Assignees

  • 吉安伊戈尔电气有限公司

Dates

Publication Date
20260508
Application Date
20250527

Claims (9)

  1. 1. The double-tube flyback switching power supply is characterized by comprising a PFC module, an auxiliary driving module, a main driving module, a double-tube circuit and a transformer T1, wherein the PFC module is respectively and electrically connected with the auxiliary driving module and the main driving module, the auxiliary driving module is electrically connected with a primary winding of the transformer T1 through the double-tube circuit, and the main driving module is electrically connected with the primary winding of the transformer T1; The PFC module is composed of a PFC chip U1 and a peripheral circuit thereof, wherein the peripheral circuit of the PFC chip U1 is provided with a quick start circuit, and the quick start circuit is integrally packaged in the PFC chip U1; The auxiliary driving module is composed of a double-tube driving chip U2 and peripheral circuits thereof, and the double-tube circuits are integrally packaged in the double-tube driving chip U2; The main driving module is composed of a single-tube driving chip U3 and peripheral circuits thereof, a switch signal end is additionally arranged on the single-tube driving chip U3, and the switch signal end is electrically connected with the input end of the double-tube driving chip U2.
  2. 2. The dual-tube flyback switching power supply of claim 1, wherein the quick start circuit comprises a MOS tube Q1, a resistor R2, a voltage stabilizing source DZ1 and a diode D10, wherein one end of the resistor R1 is electrically connected with one end of the resistor R2, the other end of the resistor R1 and a grid electrode of the MOS tube Q1 are electrically connected with a cathode of the voltage stabilizing source DZ1, an anode of the voltage stabilizing source DZ1 is grounded, the other end of the resistor R2 is electrically connected with a drain electrode of the MOS tube Q1, a source electrode of the MOS tube Q1 is electrically connected with an anode of the diode D10, and a cathode of the diode PFC 10 is electrically connected with a power end of the diode PFC chip U1; One end of the resistor R1 is used as a new pin HV end of the PFC chip U1 and is used for being electrically connected with a VBUS power supply bus.
  3. 3. The dual-tube flyback switching power supply of claim 1, wherein the PFC chip U1 is of type OB3674.
  4. 4. The dual-tube flyback switching power supply of claim 1, wherein the dual-tube circuit comprises a resistor R20, a resistor R21, a resistor R22, a resistor R23, a MOS tube Q3 and a MOS tube Q4, one end of the resistor R22 is electrically connected with the high-order output end of the dual-tube driving chip U2, the other end of the resistor R22 and one end of the resistor R23 are electrically connected with the grid electrode of the MOS tube Q4, the other end of the resistor R23 and the source electrode of the MOS tube Q4 are electrically connected with the drain electrode of the MOS tube Q3, the grid electrode of the MOS tube Q3 and one end of the resistor R21 are electrically connected with one end of the resistor R20, the other end of the resistor R21 and the source electrode of the MOS tube Q3 are grounded, and the other end of the resistor R20 and the low-order output end of the dual-tube driving chip U2 are electrically connected; The pin of the low-order output end of the double-tube driving chip U2 is canceled, the drain electrode of the MOS tube Q4 replaces the high-order output end of the double-tube driving chip U2 to be used as a pin, and the source electrode of the MOS tube Q4 replaces the high-voltage floating power supply end of the double-tube driving chip U2 to be used as a pin.
  5. 5. The dual-tube flyback switching power supply of claim 1, wherein the dual-tube driving chip U2 is BP6914.
  6. 6. The dual-tube flyback switching power supply of claim 1, wherein the gate lead-out of the built-in MOS tube of the single-tube driving chip U3 is used as the switching signal terminal.
  7. 7. The dual-tube flyback switching power supply of claim 1, wherein the single-tube driving chip U3 is BP3187.
  8. 8. The double-tube flyback switching power supply of claim 1, further comprising a synchronous rectification module, wherein the secondary winding of the transformer T1 is electrically connected with the synchronous rectification module; The synchronous rectification module is formed by integrating and packaging a synchronous rectification chip U4 and peripheral circuits thereof.
  9. 9. The dual-tube flyback switching power supply of claim 8, wherein the synchronous rectification chip U4 is KP4050.

Description

Double-tube flyback switching power supply Technical Field The utility model relates to the technical field of switching power supplies, in particular to a double-tube flyback switching power supply. Background At present, in order to realize ultra-high efficiency, a PFC+double-tube flyback (namely, double-tube quasi-resonant flyback technology) scheme is provided in the switching power supply for LED driving, and the power conversion topological design of the switching power supply enables power to be multiplied, so that the performance of the switching power supply in the aspects of energy efficiency/EMC/temperature rise and the like is improved, the application range is greatly widened, and the power limiting anxiety of customers is obviously relieved. More importantly, the pfc+dual-tube flyback scheme has higher power density than the pfc+llc scheme or the pfc+single-tube flyback scheme. However, the existing dual-tube flyback switching power supply generally adopts a KP2202B+KP85405 chip combined frame, the upper and lower dual-tubes are controlled by KP85405 chips, the dual-tube control logic design is complex, and the heat is concentrated. On the other hand, the peripheral circuits of the chips of the existing switching power supply all adopt discrete components, so that a lot of circuit board space is occupied, the discrete components are required to be continuously inserted and mounted and welded in the manufacturing process of the circuit board of the switching power supply, and the production efficiency is low. Disclosure of utility model Aiming at the defects, the utility model aims to provide a double-tube flyback switching power supply, which solves the problems that single-chip driving double-tube control is difficult, and the peripheral circuits of multiple chips in the switching power supply have more discrete components, occupy the space of a circuit board and have low production efficiency. To achieve the purpose, the utility model adopts the following technical scheme: The double-tube flyback switching power supply comprises a PFC module, an auxiliary driving module, a main driving module, a double-tube circuit and a transformer T1, wherein the PFC module is respectively and electrically connected with the auxiliary driving module and the main driving module, the auxiliary driving module is electrically connected with a primary winding of the transformer T1 through the double-tube circuit, and the main driving module is electrically connected with the primary winding of the transformer T1; The PFC module is composed of a PFC chip U1 and a peripheral circuit thereof, wherein the peripheral circuit of the PFC chip U1 is provided with a quick start circuit, and the quick start circuit is integrally packaged in the PFC chip U1; The auxiliary driving module is composed of a double-tube driving chip U2 and peripheral circuits thereof, and the double-tube circuits are integrally packaged in the double-tube driving chip U2; The main driving module is composed of a single-tube driving chip U3 and peripheral circuits thereof, a switch signal end is additionally arranged on the single-tube driving chip U3, and the switch signal end is electrically connected with the input end of the double-tube driving chip U2. Further, the quick starting circuit comprises a MOS tube Q1, a resistor R2, a voltage stabilizing source DZ1 and a diode D10, wherein one end of the resistor R1 is electrically connected with one end of the resistor R2, the other end of the resistor R1 and the grid electrode of the MOS tube Q1 are electrically connected with the cathode of the voltage stabilizing source DZ1, the anode of the voltage stabilizing source DZ1 is grounded, the other end of the resistor R2 is electrically connected with the drain electrode of the MOS tube Q1, the source electrode of the MOS tube Q1 is electrically connected with the anode of the diode D10, and the cathode of the diode D10 is electrically connected with the power end of the PFC chip U1; One end of the resistor R1 is used as a new pin HV end of the PFC chip U1 and is used for being electrically connected with a VBUS power supply bus. Further, the PFC chip U1 is of a type OB3674. Further, the double-tube circuit comprises a resistor R20, a resistor R21, a resistor R22, a resistor R23, a MOS tube Q3 and a MOS tube Q4, wherein one end of the resistor R22 is electrically connected with the high-order output end of the double-tube driving chip U2, the other end of the resistor R22 and one end of the resistor R23 are electrically connected with the grid electrode of the MOS tube Q4, the other end of the resistor R23 and the source electrode of the MOS tube Q4 are electrically connected with the drain electrode of the MOS tube Q3, the grid electrode of the MOS tube Q3 and one end of the resistor R21 are electrically connected with one end of the resistor R20, the other end of the resistor R21 and the source electrode of the MOS tube Q3 are grounded, and th