Switching power supply efficiency optimization control circuit
By designing a switching power supply efficiency optimization control circuit in the power supply circuit, and using the transformer and control chip to match the induction resistor and switch tube, the problem of power supply circuits requiring high-voltage MOS tubes under fluctuating voltage is solved, and the effect of reducing heat generation and improving efficiency is achieved.
Patent Information
- Application Number
- CN202421365707.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-14
- Publication Date
- 2025-03-25
- Estimated Expiration
- 2034-06-14
AI Technical Summary
When the existing power supply circuit faces fluctuating voltages between 90 and 400V, it is necessary to use high-voltage resistant MOS tubes to ensure stability, but this MOS tube is expensive and generates a lot of heat, which affects efficiency.
A switching power supply efficiency optimization control circuit is designed, by introducing a transformer, a control chip, an eighth diode, an induction resistor, a first switching tube and a connection resistor into the power supply circuit, the control chip and an induction resistor are used to detect the current signal, and the first switching tube is controlled to recover leakage inductance energy and output it, and reduce the leakage inductance peak voltage.
It realizes that without adding high-voltage resistant MOS tubes, reduces heat generation, improves the working efficiency of the power supply circuit, and enables conventional high-voltage switching tubes to adapt to high-voltage environments, and the circuit is simple and unified.
Smart Images
Figure CN222674150U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power supply circuits, and in particular to a switching power supply efficiency optimization control circuit. Background Art
[0002] With the continuous development of power supply industry technology, power supplies need to meet the needs of more foreign markets, but the voltage in some areas is unstable and often fluctuates between 90 and 400V. In order to make the power supply meet the fluctuating voltage (90-400V), existing power supplies usually need to use MOS tubes with higher withstand voltage. However, high-voltage MOS tubes are expensive, and in order to meet the high-voltage resistance requirements, the withstand voltage requirements of high-voltage MOS tubes can be as high as 800-900V, which is not compatible with conventional high-voltage MOS tubes. Moreover, the higher the withstand voltage, the greater the internal resistance of the MOS tube, resulting in more heat and low working efficiency. Utility Model Content
[0003] The technical problem to be solved by the utility model is to provide a switching power supply efficiency optimization control circuit, so as to reduce heat generation and improve the working efficiency of the power supply circuit without adding a high-voltage MOS tube in the power supply circuit.
[0004] In order to solve the above technical problems, the purpose of the utility model is achieved through the following technical solutions: providing a switching power supply efficiency optimization control circuit, which is applied to a power supply circuit and electrically connected to a PWM control module of the power supply circuit. The switching power supply efficiency optimization control circuit includes a transformer, a control chip, an eighth diode, an induction resistor, a first switch tube and a connection resistor. The opposite-name end of the primary winding of the transformer is connected to the power supply voltage end, and the power supply voltage end is connected to the input end of the first switch tube after being connected in parallel with a first capacitor and a ninth diode. The output end of the first switch tube is connected to the first end of the induction resistor and the current detection pin of the control chip. The PWM control module is connected to the second end of the induction resistor and the same-name end of the primary winding of the transformer through a connection switch tube. The control pin of the control chip is connected to the control end of the first switch tube after being connected to the connection resistor. The anode of the eighth diode is connected to the power supply voltage end, and the cathode of the eighth diode is connected to the power supply voltage pin of the control chip.
[0005] The beneficial technical effect of the utility model is that the switching power supply efficiency optimization control circuit of the utility model connects the control chip to the primary winding of the transformer to cooperate with the first switch tube, the induction resistor and the first capacitor to control the on and off of the first switch tube according to the current signal detected passing through the induction resistor, so that the leakage inductance energy generated by the transformer can be recovered to the first capacitor, and then output by the first capacitor through the transformer to the secondary winding of the transformer, thereby improving the working efficiency and reducing the leakage inductance peak voltage generated by the transformer, so that the voltage resistance requirement of the connection switch tube connected to the primary winding of the transformer for connecting to the PWM control module of the power supply circuit is relatively low, and the general conventional high-voltage switch tube can adapt to the high-voltage environment, thereby realizing the uniformity of the switch tube, and there is no need to set a high-voltage MOS tube in the power supply circuit, thereby reducing heat generation and simplifying the circuit. BRIEF DESCRIPTION OF THE DRAWINGS
[0006] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0007] Figure 1 A circuit diagram of a switching power supply efficiency optimization control circuit provided in an embodiment of the utility model. DETAILED DESCRIPTION
[0008] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0009] See also Figure 1 , Figure 1A circuit diagram of a switching power supply efficiency optimization control circuit provided by an embodiment of the utility model, wherein the switching power supply efficiency optimization control circuit is applied to a power supply circuit and is electrically connected to a PWM control module 201 of the power supply circuit. The switching power supply efficiency optimization control circuit comprises a transformer T1, a control chip U1, an eighth diode D8, an induction resistor R1, a first switch tube Q1 and a connection resistor R3. The opposite-name end of the primary winding of the transformer T1 is connected to a power supply voltage terminal Vbus, and the power supply voltage terminal Vbus is connected to the first switch tube Q1 through a first capacitor C1 and a ninth diode D9 connected in parallel. The input end of the first switch tube Q1 is connected to the first end of the sensing resistor R1 and the current detection pin CS of the control chip U1. The PWM control module 201 is connected to the second end of the sensing resistor R1 and the same-name end of the primary winding of the transformer T1 through the connecting switch tube Q2. The control pin of the control chip U1 is connected to the control end of the first switch tube Q1 through the connecting resistor R3. The anode of the eighth diode D8 is connected to the power supply voltage terminal VCC, and the cathode of the eighth diode D8 is connected to the power supply voltage pin of the control chip U1.
[0010] Among them, the first capacitor C1 and the ninth diode D9 are connected in parallel with each other, the first end of the first capacitor C1 is connected to the anode of the ninth diode D9, the second end of the first capacitor C1 is connected to the cathode of the ninth diode D9, and the power supply voltage terminal Vbus is connected to the input end of the first switch tube Q1 after passing through the first capacitor C1 and the ninth diode D9 connected in parallel with each other, then the power supply voltage terminal Vbus is connected to the first end of the first capacitor C1 and the anode of the ninth diode D9, and the input end of the first switch tube Q1 is connected to the second end of the first capacitor C1 and the cathode of the ninth diode D9. The switching power supply efficiency optimization control circuit connects the control chip U1 to the primary winding of the transformer T1 to cooperate with the first switch tube Q1, the induction resistor R1 and the first capacitor C1 to control the on and off of the first switch tube Q1 according to the current signal detected passing through the induction resistor R1, so that the leakage inductance energy generated by the transformer T1 can be recovered to the first capacitor C1, and then output by the first capacitor C1 through the transformer T1 to the secondary winding of the transformer T1, thereby improving the working efficiency and reducing the leakage inductance peak voltage generated by the transformer T1, so that the voltage resistance requirement of the connection switch tube Q2 connected to the primary winding of the transformer T1 and connected to the PWM control module 201 of the power supply circuit is relatively low, and a general conventional high-voltage switch tube can adapt to the high-voltage environment, thereby realizing the uniformity of the switch tube, and there is no need to set a high-voltage MOS tube in the power supply circuit, thereby reducing heat generation and simplifying the circuit.
[0011] Preferably, in this embodiment, the ninth diode D9 is a unidirectional transient voltage suppression diode.
[0012] Specifically, in this embodiment, the input end of the connection switch tube Q2 is connected to the second end of the induction resistor R1 and the same-name end of the primary winding of the transformer T1, the control end of the connection switch tube Q2 is connected to the PWM control module 201, the output end of the connection switch tube Q2 is connected to the first grounding resistor Rs1, and the current detection pin CS1 of the main control module of the power supply circuit is electrically connected between the output end of the connection switch tube Q2 and the first grounding resistor Rs1.
[0013] Specifically, in this embodiment, the same-name end of the primary winding of the transformer T1 is connected to the negative power supply pin VSS of the control chip U1, the working voltage pin VDD of the control chip U1 is connected to the same-name end of the primary winding of the transformer T1 through the fourth capacitor C4, and the setting pin SET of the control chip U1 is connected to the same-name end of the primary winding of the transformer T1 through the second resistor R2 and the fifth capacitor C5 connected in parallel.
[0014] Specifically, in this embodiment, the control chip U1 is a chip of model HF30X.
[0015] Specifically, in this embodiment, both the first switch tube Q1 and the connecting switch tube Q2 are NMOS tubes. The power supply voltage terminal Vbus is connected to the first end of the first capacitor C1 and the anode of the ninth diode D9, the drain of the first switch tube Q1 is connected to the second end of the first capacitor C1 and the cathode of the ninth diode D9, the source of the first switch tube Q1 is connected to the first end of the sensing resistor R1 and the current detection pin CS of the control chip U1, the control pin of the control chip U1 is connected to the gate of the first switch tube Q1 through the connecting resistor R3, the drain of the connecting switch tube Q2 is connected to the second end of the sensing resistor R1 and the same-name end of the primary winding of the transformer T1, the gate of the connecting switch tube Q2 is connected to the PWM control module 201, and the source of the connecting switch tube Q2 is connected to the first grounding resistor Rs1.
[0016] Specifically, in this embodiment, the switching power supply efficiency optimization control circuit also includes a synchronous rectification controller U2 and a third switch tube Q3, wherein the synchronous rectification controller U2 is connected to the secondary winding of the transformer T1, the control end of the third switch tube Q3 is connected to the drive pin of the synchronous rectification controller U2, the input end of the third switch tube Q3 is connected to the opposite end of the secondary winding of the transformer T1, the output end of the third switch tube Q3 is grounded, the same end of the secondary winding of the transformer T1 is connected to the positive electrode of the third polarity capacitor EC3, and the negative electrode of the third polarity capacitor EC3 is grounded. By connecting the synchronous rectification controller U2 to the secondary winding of the transformer T1 for rectification, power loss can be reduced, work efficiency can be improved, and the output of the transformer T1 can be controlled by controlling the on-off of the third switch tube Q3 in cooperation with the third switch tube Q3.
[0017] Specifically, in this embodiment, the same-name end of the secondary winding of the transformer T1 is connected to the high voltage pin HV of the synchronous rectification controller U2, the opposite-name end of the secondary winding of the transformer T1 is connected to the induction voltage pin VSEN of the synchronous rectification controller U2 through the fifth resistor R5, the working voltage pin VDD of the synchronous rectification controller U2 is connected to the ground and the output end of the third switch tube Q3 through the third capacitor C3, and the resistance setting pin RSET of the synchronous rectification controller U2 is connected to the ground and the output end of the third switch tube Q3 through the fourth resistor R4.
[0018] Specifically, in this embodiment, the third switch tube Q3 is an NMOS tube, and the synchronous rectification controller U2 is a chip of model SC35XX. The gate of the third switch tube Q3 is connected to the drive pin of the synchronous rectification controller U2, the drain of the third switch tube Q3 is connected to the opposite end of the secondary winding of the transformer T1, and the source of the third switch tube Q3 is connected to the third capacitor C3, the fourth resistor R4 and the ground.
[0019] Specifically, in this embodiment, the same-name end of the auxiliary winding of the transformer T1 is connected to the auxiliary voltage terminal Vaux, and the opposite-name end of the auxiliary winding of the transformer T1 is grounded.
[0020] Based on the above design, when working, the power supply voltage end supplies power to the control chip through the eighth diode, the control chip starts internal startup, the control chip detects the current signal through the sensing resistor, the current sensing pin of the control chip senses the current from the leakage inductance, and when the induced voltage obtained by the current sensing pin of the control chip reaches the preset conduction value, the control pin of the control chip outputs a driving signal to control the first switch tube to be turned on after passing through the third resistor, and the leakage inductance energy is recovered to the first capacitor, and then output by the first capacitor through the transformer and the secondary winding of the transformer; when the induced voltage obtained by the current sensing pin of the control chip reaches the zero-crossing threshold, the control pin of the control chip controls the first switch tube to be turned off.
[0021] In summary, the switching power supply efficiency optimization control circuit of the utility model connects the control chip to the primary winding of the transformer to cooperate with the first switch tube, the induction resistor and the first capacitor to control the on and off of the first switch tube according to the current signal detected passing through the induction resistor, so that the leakage inductance energy generated by the transformer can be recovered to the first capacitor, and then output by the first capacitor through the transformer to the secondary winding of the transformer, thereby improving the working efficiency and reducing the leakage inductance peak voltage generated by the transformer, so that the voltage resistance requirement of the connection switch tube connected to the primary winding of the transformer for connecting to the PWM control module of the power supply circuit is relatively low, and a general conventional high-voltage switch tube can adapt to the high-voltage environment, thereby realizing the uniformity of the switch tube, and there is no need to set a high-voltage MOS tube in the power supply circuit, thereby reducing heat generation and simplifying the circuit.
[0022] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A switching power supply efficiency optimization control circuit, characterized in that: Applied to a power supply circuit, electrically connected to a PWM control module of the power supply circuit, the switching power supply efficiency optimization control circuit comprises a transformer, a control chip, an eighth diode, an induction resistor, a first switch tube and a connection resistor, the opposite-name end of the primary winding of the transformer is connected to the power supply voltage end, the power supply voltage end is connected to the input end of the first switch tube through a first capacitor and a ninth diode connected in parallel, the output end of the first switch tube is connected to the first end of the induction resistor and the current detection pin of the control chip, the PWM control module is connected to the second end of the induction resistor and the same-name end of the primary winding of the transformer through a connection switch tube, the control pin of the control chip is connected to the control end of the first switch tube through the connection resistor, the anode of the eighth diode is connected to the power supply voltage end, and the cathode of the eighth diode is connected to the power supply voltage pin of the control chip.
2. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The input end of the connecting switch tube is connected to the second end of the inductive resistor and the same-name end of the primary winding of the transformer, the control end of the connecting switch tube is connected to the PWM control module, the output end of the connecting switch tube is connected to the first grounding resistor, and the current detection pin of the main control module of the power supply circuit is electrically connected between the output end of the connecting switch tube and the first grounding resistor.
3. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The same-name end of the primary winding of the transformer is connected to the negative power supply pin of the control chip, the working voltage pin of the control chip is connected to the same-name end of the primary winding of the transformer through the fourth capacitor, and the setting pin of the control chip is connected to the same-name end of the primary winding of the transformer through the second resistor and the fifth capacitor connected in parallel.
4. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The control chip is a chip of model HF30X.
5. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The first switch tube and the connecting switch tube are both NMOS tubes.
6. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The switching power supply efficiency optimization control circuit also includes a synchronous rectification controller and a third switch tube, the synchronous rectification controller is connected to the secondary winding of the transformer, the control end of the third switch tube is connected to the drive pin of the synchronous rectification controller, the input end of the third switch tube is connected to the opposite end of the secondary winding of the transformer, the output end of the third switch tube is grounded, the same end of the secondary winding of the transformer is connected to the positive electrode of the third polarity capacitor, and the negative electrode of the third polarity capacitor is grounded.
7. The switching power supply efficiency optimization control circuit according to claim 6, characterized in that: The like-name end of the secondary winding of the transformer is connected to the high voltage pin of the synchronous rectification controller, the opposite-name end of the secondary winding of the transformer is connected to the induction voltage pin of the synchronous rectification controller through a fifth resistor, the working voltage pin of the synchronous rectification controller is connected to the ground and the output end of the third switch tube through a third capacitor, and the resistance setting pin of the synchronous rectification controller is connected to the ground and the output end of the third switch tube through a fourth resistor.
8. The switching power supply efficiency optimization control circuit according to claim 6, characterized in that: The third switch tube is an NMOS tube, and the synchronous rectification controller is an SC35XX chip.
9. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The ninth diode is a unidirectional transient voltage suppression diode.
10. The switching power supply efficiency optimization control circuit according to claim 1, characterized in that: The same-name end of the auxiliary winding of the transformer is connected to the auxiliary voltage end, and the opposite-name end of the auxiliary winding of the transformer is grounded.