Search

CN-122001222-A - Power supply circuit with positive and negative output voltages

CN122001222ACN 122001222 ACN122001222 ACN 122001222ACN-122001222-A

Abstract

The invention discloses a power supply circuit with positive and negative output voltages. The power supply circuit comprises a primary side circuit, a transformer and a secondary side circuit. The primary side circuit comprises a resonant converter. The transformer includes a primary side coil and a secondary side coil. The secondary side circuit includes a positive voltage output circuit and a negative voltage output circuit. The resonant converter is connected to the primary side coil. The positive voltage output circuit and the negative voltage output circuit are connected with the secondary side coil and are configured to output positive output voltage and negative output voltage respectively.

Inventors

  • CHEN ZHISHAN

Assignees

  • 光宝科技股份有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (11)

  1. 1. A power supply circuit having positive and negative output voltages, the power supply circuit comprising: A primary side circuit comprising A resonant converter; a transformer including a primary side coil and a secondary side coil, the resonant converter being connected to the primary side coil, and A secondary side circuit comprising: A positive voltage output circuit connected to the secondary side coil and configured to output a positive output voltage, and And the negative voltage output circuit is connected with the secondary side coil and is configured to output a negative output voltage.
  2. 2. The power supply circuit with positive and negative output voltages of claim 1, wherein the secondary side coil of the transformer comprises a first sub-secondary side coil and a second sub-secondary side coil; Wherein a first end of the first secondary side coil is connected with the positive voltage output circuit, and a second end of the first secondary side coil is grounded; the first end of the second secondary side coil is grounded, and the second end of the second secondary side coil is connected with the positive voltage output circuit and the negative voltage output circuit.
  3. 3. The power supply circuit with positive and negative output voltages according to claim 2, wherein the negative voltage output circuit comprises: a first reverse diode, and An inverting capacitor; The cathode of the first inverting diode is connected with the second end of the second secondary side coil, the anode of the first inverting diode is connected with the first end of the inverting capacitor, and the second end of the inverting capacitor is grounded.
  4. 4. A power supply circuit having positive and negative output voltages as claimed in claim 3, wherein the voltage of the inverting capacitor is the negative output voltage.
  5. 5. The power supply circuit of claim 3, wherein the negative voltage output circuit further comprises: And the cathode of the second inverting diode is connected with the first end of the first secondary side coil of the first sub, and the anode of the second inverting diode is connected with the first end of the inverting capacitor.
  6. 6. The power supply circuit with positive and negative output voltages according to claim 2, wherein the negative voltage output circuit further comprises: A first transistor, and An inverting capacitor; The first end of the first transistor is connected with the second end of the second secondary side coil, the second end of the first transistor is connected with the first end of the inverting capacitor, the control end of the first transistor is coupled with a first control voltage, and the second end of the inverting capacitor is grounded.
  7. 7. The power supply circuit of claim 6, wherein the voltage of the inverting capacitor is the negative output voltage.
  8. 8. The power supply circuit with positive and negative output voltages of claim 5, wherein the negative voltage output circuit further comprises: And a first end of the second transistor is connected with the first end of the first secondary side coil, a second end of the second transistor is connected with the first end of the inverting capacitor, and a control end of the second transistor is coupled with a second control voltage.
  9. 9. The power supply circuit with positive and negative output voltages according to claim 2, wherein the positive voltage output circuit comprises: A first diode, and An output capacitance; the positive output voltage is obtained by connecting the anode of the first diode with the first end of the first secondary side coil, the cathode of the first diode is connected with the first end of the output capacitor, the second end of the output capacitor is grounded, and the voltage of the output capacitor is the positive output voltage.
  10. 10. The power supply circuit with positive and negative output voltages according to claim 9, wherein the positive voltage output circuit comprises: And the anode of the second diode is connected with the second end of the second secondary side coil, and the cathode of the second diode is connected with the first end of the output capacitor.
  11. 11. The power supply circuit with positive and negative output voltages according to claim 1, further comprising a feedback circuit, a coupling circuit, a resonance control circuit, a protection circuit, and a correction control circuit, wherein the primary side circuit further comprises a filter circuit, a bridge rectifier, and a power factor correction conversion circuit; Wherein the feedback circuit outputs a feedback signal according to the positive output voltage or the negative output voltage; wherein the resonant control circuit compares the feedback signal received from the feedback circuit through the coupling circuit with a voltage threshold received from the protection circuit to control the resonant converter; the filter circuit filters an input alternating voltage to generate a filter voltage, the bridge rectifier receives the filter voltage and rectifies the filter voltage to output a rectified voltage, and the power factor correction conversion circuit receives the rectified voltage to output an input direct voltage and inputs the input direct voltage to the resonant converter.

Description

Power supply circuit with positive and negative output voltages Technical Field The present invention relates to power supply circuits, and more particularly to a power supply circuit with positive and negative output voltages. Background Resonant converters are an indispensable device for many electronic devices. Resonant converters, such as LLC (inductor-inductor-capacitor) resonant converters, are commonly used to convert a dc input voltage to a dc output voltage. However, the conventional resonant converter can only convert a single output voltage, for example, a single output voltage having a positive voltage value, and cannot simultaneously supply one output voltage having a positive voltage value and another output voltage having a negative voltage value, which cannot be applied to more applications. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a power supply circuit with positive and negative output voltages. The power supply circuit with positive and negative output voltages comprises a primary side circuit, a transformer and a secondary side circuit. The primary side circuit includes a resonant converter. The transformer includes a primary side coil and a secondary side coil. The resonant converter is connected to the primary side coil. The secondary side circuit includes a positive voltage output circuit and a negative voltage output circuit. The positive voltage output circuit is connected with the secondary side coil and is configured to output a positive output voltage. The negative voltage output circuit is connected with the secondary side coil and is configured to output a negative output voltage. As described above, the present invention provides a power supply circuit having positive and negative output voltages. Compared with the traditional power supply circuit which can only supply positive output voltage, the power supply circuit can supply positive output voltage and negative output voltage. Therefore, the power supply circuit of the present invention is suitable for use in a variety of applications. For a further understanding of the nature and the technical aspects of the present invention, reference should be made to the following detailed description of the invention and the accompanying drawings, which are provided for purposes of reference only and are not intended to limit the invention. Drawings Fig. 1 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a first embodiment of the present invention. Fig. 2 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a second embodiment of the present invention. Fig. 3 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a third embodiment of the present invention. Fig. 4 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a fourth embodiment of the present invention. Fig. 5 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a fifth embodiment of the present invention. Fig. 6 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a sixth embodiment of the present invention. Fig. 7 is a circuit diagram of a power supply circuit with positive and negative output voltages according to a seventh embodiment of the present invention. Detailed Description The following embodiments of the present invention are described in terms of specific examples, and those skilled in the art will appreciate the advantages and effects of the present invention from the disclosure herein. The invention is capable of other and different embodiments and its several details are capable of modification and variation in various respects, all from the point of view and application, all without departing from the spirit of the present invention. The drawings of the present invention are merely schematic illustrations, and are not intended to be drawn to actual dimensions. The following embodiments will further illustrate the related art content of the present invention in detail, but the disclosure is not intended to limit the scope of the present invention. In addition, the term "or" as used herein shall include any combination of one or more of the associated listed items as the case may be. Please refer to fig. 1, which is a circuit diagram of a power supply circuit with positive and negative output voltages according to a first embodiment of the present invention. As shown in fig. 1, in the first embodiment, the power supply circuit with positive and negative output voltages of the present invention includes a primary side circuit PRYT, a transformer TR, and a secondary side circuit SEDT1. The primary side circuit PRYT includes a resonant converter PR1. For example, the resonant converter PR1 may be an LLC (inducto