Flyback auxiliary voltage stabilizing circuit

Abstract

The utility model discloses a flyback type auxiliary voltage stabilizing circuit which comprises an input module, a primary main winding module, a switch module, a primary auxiliary winding module, a secondary main winding module and a secondary auxiliary winding module, the input end of the input module is connected with direct current input voltage, and the output end of the input module is connected with the primary main winding module. The control end of the switch module is connected with a control signal, the switch module is connected with the primary main winding module, the primary auxiliary winding module is connected with the input module, and the primary auxiliary winding module, the secondary main winding module and the secondary auxiliary winding module are respectively coupled with the primary main winding module. Input voltage is converted through switching characteristics, so that a voltage reduction function is realized, the conversion efficiency is high, the power is large, a large amount of energy loss is reduced, components can be prevented from being overheated and damaged, the stability of the circuit is improved, an output part acquires output voltage in a coupling mode, various different voltages can be output, and the applicability of the circuit is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of voltage stabilizing circuits, and particularly relates to a flyback auxiliary voltage stabilizing circuit. Background Art

[0002] At present, in a buck circuit, a linear voltage regulator is often used to step down the input voltage to obtain the voltage required by the subsequent circuit. However, the linear voltage regulator has the following deficiencies:

[0003] First, low efficiency. The linear voltage regulator stabilizes the output voltage by adjusting the variable resistor inside it. During this process, a certain voltage drop will occur, resulting in energy loss.

[0004] Second, large heat generation. When the difference between the input voltage and the output voltage is large, it will cause large energy loss. Since the energy loss is converted into heat, the linear voltage regulator will generate a large amount of heat during operation.

[0005] Third, single output voltage. The linear voltage regulator can only step down the input voltage to a lower output voltage level, and cannot achieve the functions of boosting or buck-boosting. This limits its use in some application scenarios that require boosting or polarity inversion. Summary of the Utility Model

[0006] The purpose of the utility model is to provide a flyback auxiliary voltage stabilizing circuit. This circuit converts the input voltage through the switching characteristics to achieve the buck function, with high conversion efficiency, large power, reducing a large amount of energy loss, and can avoid overheating and damage of components, improving the stability of the circuit. The output part obtains the output voltage by means of coupling, and can output a variety of different voltages, improving the applicability of the circuit.

[0007] In order to achieve the above-mentioned utility model purpose, the technical scheme adopted by the utility model is as follows:

[0008] According to one aspect of the present invention, a flyback auxiliary voltage stabilizing circuit is provided, including an input module, a primary main winding module, a switching module, a primary auxiliary winding module, a secondary main winding module, and a secondary auxiliary winding module;

[0009] The input end of the input module is connected to the DC input voltage, and the output end of the input module is connected to the primary main winding module;

[0010] The control end of the switching module is connected to the control signal, and the switching module is connected to the primary main winding module;

[0011] The primary auxiliary winding module is connected to the input module;

[0012] The primary auxiliary winding module, the secondary main winding module, and the secondary auxiliary winding module are respectively coupled to the primary main winding module.

[0013] Preferably, the input module includes a diode D8 and a fuse. The anode of the diode D8 is connected to the input voltage, the cathode of the diode D8 is connected to the fuse, and the end of the fuse away from the diode D8 is connected to the primary main winding module.

[0014] Preferably, the primary main winding module includes a first coil. One end of the first coil is connected to the end of the fuse away from the diode D8, and the other end of the first coil is connected to the switch module.

[0015] Preferably, the switch module includes a transistor Q9. The drain of the transistor Q9 is connected to the first coil, the gate of the transistor Q9 is connected to the control signal through a resistor R54, and the source of the transistor Q9 is grounded through a resistor R61.

[0016] Preferably, the primary auxiliary winding module includes a diode D6, a diode D12, and a second coil. The cathode of the diode D6 is connected to the fuse through a resistor R52, the anode of the diode D6 is connected to the cathode of the diode D12, the anode of the diode D12 is connected to one end of the second coil, the end of the second coil away from the diode D12 is grounded, the cathode of the diode is connected to the first voltage, and the cathode of the diode D6 is connected to the second voltage.

[0017] Preferably, the secondary main winding module includes a third coil, a diode D11, and a fourth coil. One end of the third coil is connected to the anode of the diode D11, the cathode of the diode D11 is the first voltage output terminal, one end of the fourth coil is connected in series with the end of the third coil away from the diode D11 and then grounded, and the other end of the fourth coil is the second voltage output terminal.

[0018] Preferably, the secondary auxiliary winding module includes a fifth coil and a sixth coil, and the fifth coil and the sixth coil are connected in parallel.

[0019] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present utility model are as follows:

[0020] The present utility model converts the input voltage through the switching characteristics, thereby realizing the step-down function, with high conversion efficiency, large power, reducing a large amount of energy loss, and avoiding overheating and damage of components, improving the stability of the circuit. The output part obtains the output voltage by means of coupling, and can output multiple different voltages, improving the applicability of the circuit. Description of the Drawings

[0021] Figure 1 is the circuit schematic diagram of the present utility model;

[0022] Figure 2 is the circuit schematic diagram of the current mode PWM controller of the present utility model. Specific embodiments

[0023] To make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the following preferred embodiments are cited with reference to the accompanying drawings for further detailed description of the present utility model. However, it should be noted that many details listed in the specification are only for enabling the reader to have a thorough understanding of one or more aspects of the utility model, and these aspects of the present utility model can be implemented even without these specific details.

[0024] Please refer to Figure 1 , the present utility model provides a flyback auxiliary voltage stabilizing circuit, and the technical solution is as follows:

[0025] A flyback auxiliary voltage stabilizing circuit includes an input module, a primary main winding module, a switching module, a primary auxiliary winding module, a secondary main winding module and a secondary auxiliary winding module. The input module includes a diode D8 and a fuse. The anode of the diode D8 is the input terminal, and the anode of the diode D8 is connected to the input voltage. In this embodiment, the input voltage is the voltage provided by the battery. The cathode of the diode D8 is connected to one end of the fuse, and the end of the fuse far from the diode D8 is grounded through a capacitor C47 and a capacitor C51, and the end of the fuse far from the diode D8 is connected to the primary main winding module.

[0026] The primary main winding module includes a first coil. The first end of the first coil is connected to the end of the fuse far from the diode D8. The first end of the first coil is grounded through two series-connected capacitors, which are capacitor 130 and capacitor 131 respectively. One end of the capacitor 131 is connected to the first coil, the other end of the capacitor 131 is connected to one end of the capacitor 130, and the other end of the capacitor 130 is grounded. A discharge module is arranged between the first end and the second end of the first coil. The discharge module includes a diode D7, a capacitor C32 and a resistor R51. The anode of the diode D7 is connected to the second end of the first coil, the cathode of the diode D7 is connected to one end of the resistor R51, the other end of the resistor R51 is connected to the first end of the first coil, and the capacitor C32 is connected in parallel with the resistor R51. The second end of the first coil is connected to the switching module.

[0027] The switching module includes a transistor Q9. The drain of the transistor Q9 is connected to the second end of the first coil. The gate of the transistor Q9 is connected to a control signal through a resistor R54, and the source of the transistor Q9 is grounded through a resistor R61. Among them, as Figure 2As shown, the control signal is provided by a current-mode PWM controller, the model of which is TL2843B. The source of transistor Q9 is connected to pin 6 of the current-mode PWM controller through resistor R58, and the signal is fed back to control the chip to send out control signals to control the conduction and cut-off of the transistor.

[0028] On the same side of the first coil, there is a primary auxiliary winding module. The primary auxiliary winding module includes diode D6, diode D12 and a second coil. The cathode of diode D6 is connected to the fuse through resistor R52. One end of resistor R52 is connected to diode D6, and the other end is connected to the end of the fuse far from diode D8. A first voltage is connected at the cathode of diode D6. The anode of diode D6 is connected to the cathode of diode D12, and the anode of diode D12 is connected to one end of the second coil. The other end of the second coil is grounded. The node where the anode of diode D6 is connected to the cathode of diode D12 is grounded through capacitor C38 and capacitor C42. The second coil is coupled with the first coil, and the second coil can provide a voltage source for protection. Under specific conditions, such as when the input voltage changes or the secondary winding output is overloaded, the internal power supply can be stabilized by adjusting the first voltage and the second voltage to prevent the device from being damaged.

[0029] The secondary main winding module includes a third coil, diode D11 and a fourth coil. One end of the third coil is connected to the anode of diode D11, and the cathode of diode D11 is the first voltage output terminal. The third coil is coupled with the first coil. In this embodiment, the first voltage output terminal is a positive voltage output terminal. One end of the fourth coil is connected in series with the end of the third coil far from diode D11 and then grounded, and the other end of the fourth coil is the second voltage output terminal. The fourth coil is coupled with the first coil. In this embodiment, the second voltage output terminal is a negative voltage output terminal. By connecting the third coil and the fourth coil in series and leading out and grounding the connection node between the two, the secondary main winding module can generate two voltages with opposite polarities, which is convenient for the subsequent modules to use.

[0030] The secondary auxiliary winding module includes a fifth coil and a sixth coil. The fifth coil and the sixth coil are connected in parallel, and the fifth coil is coupled with the first coil. The secondary auxiliary winding formed by the fifth coil and the sixth coil can keep the internal power supply stable. When the input voltage or load conditions change, the output voltage can be adjusted accordingly to maintain the stability and reliability of the internal power supply.

[0031] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A flyback auxiliary voltage stabilization circuit, characterized in that: It includes an input module, a primary main winding module, a switch module, a primary auxiliary winding module, a secondary main winding module and a secondary auxiliary winding module; The input end of the input module is connected to a DC input voltage, and the output end of the input module is connected to a primary main winding module; The control end of the switch module is connected to a control signal, and the switch module is connected to the primary main winding module; The primary auxiliary winding module is connected to the input module; The primary auxiliary winding module, the secondary main winding module and the secondary auxiliary winding module are respectively coupled to the primary main winding module.

2. The flyback auxiliary voltage stabilizing circuit according to claim 1, characterized in that: The input module includes a diode D8 and a fuse. The anode of the diode D8 is connected to the input voltage, the cathode of the diode D8 is connected to the fuse, and one end of the fuse away from the diode D8 is connected to the primary main winding module.

3. The flyback auxiliary voltage stabilizing circuit according to claim 2, characterized in that: The primary main winding module includes a first coil, one end of the first coil is connected to an end of the fuse away from the diode D8, and the other end of the first coil is connected to the switch module.

4. The flyback auxiliary voltage stabilizing circuit according to claim 3, characterized in that: The switch module includes a transistor Q9, a drain of the transistor Q9 is connected to the first coil, a gate of the transistor Q9 is connected to a control signal via a resistor R54, and a source of the transistor Q9 is grounded via a resistor R61.

5. The flyback auxiliary voltage stabilizing circuit according to claim 2, characterized in that: The primary auxiliary winding module includes a diode D6, a diode D12 and a second coil, the cathode of the diode D6 is connected to the fuse through a resistor R52, the anode of the diode D6 is connected to the cathode of the diode D12, the anode of the diode D12 is connected to one end of the second coil, the end of the second coil away from the diode D12 is grounded, the cathode of the diode is connected to a first voltage, and the cathode of the diode D6 is connected to a second voltage.

6. The flyback auxiliary voltage stabilizing circuit according to claim 1, characterized in that: The secondary main winding module includes a third coil, a diode D11 and a fourth coil, one end of the third coil is connected to the anode of the diode D11, the cathode of the diode D11 is the first voltage output end, one end of the fourth coil is connected in series with the end of the third coil away from the diode D11 and then grounded, and the other end of the fourth coil is the second voltage output end.

7. The flyback auxiliary voltage stabilizing circuit according to claim 1, characterized in that: The secondary auxiliary winding module includes a fifth coil and a sixth coil, and the fifth coil is connected in parallel with the sixth coil.

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