Realization circuit for power supply temperature protection

Abstract

The utility model discloses a power supply temperature protection realization circuit comprising a first diode, the first diode is connected with a second diode in parallel, a sixth diode is connected with a seventh diode in parallel, and the first diode, the second diode, the sixth diode and the seventh diode are all electrically connected with a voltage output end VIN. One end of the first diode and one end of the second diode are electrically connected with a first glass capacitor, one end of the first glass capacitor is electrically connected with the sixth diode and the seventh diode, one end of the first glass capacitor is grounded, and one end of the first glass capacitor is electrically connected with a first row resistor and a protection capacitor. One end of the protection capacitor is electrically connected with a third diode, one end of the third diode is connected with a first transformer in parallel, the current sampling angle tube of a common chip is adopted, the capacitors, the resistors, the diodes and the field-effect tube are added, power supply temperature protection is achieved, dependence on a special chip is reduced, and practicability of equipment is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply protection, in particular to a circuit for realizing power supply temperature protection. Background Art

[0002] Temperature protection is necessary for general switching power supply design. However, general temperature protection depends on the temperature protection function and pins provided by the control chip, and is designed according to specified requirements. This limits the implementation of temperature protection functions in some general designs, making it difficult to effectively protect the power supply temperature, reducing the practicality of the equipment. Utility Model Content

[0003] The utility model aims to provide a circuit for realizing power supply temperature protection, so as to solve the problem that the existing power supply temperature protection circuit relies on a dedicated chip.

[0004] In order to solve the above technical problems, the utility model provides the following technical solutions: a circuit for implementing power supply temperature protection, comprising a first diode, the first diode is connected in parallel with the second diode, and the sixth diode is connected in parallel with the seventh diode, and the first diode, the second diode, the sixth diode and the seventh diode are all electrically connected to the voltage output terminal VIN.

[0005] Furthermore, one end of the first diode and the second diode is electrically connected to a first glass capacitor, and one end of the first glass capacitor is electrically connected to the sixth diode and the seventh diode, and one end of the first glass capacitor is grounded.

[0006] Furthermore, one end of the first glass capacitor is electrically connected to the first resistor and the protection capacitor, and one end of the protection capacitor is electrically connected to the third diode, and one end of the third diode is connected in parallel with the first transformer.

[0007] Furthermore, a fourth diode is electrically connected to one side of the first transformer, and a second glass capacitor is electrically connected to one side of the fourth diode, and one side of the second glass capacitor is electrically connected to one side of the first transformer.

[0008] Furthermore, a field effect tube is electrically connected to one side of the first transformer, and one end of the field effect tube is electrically connected to a second resistor, and one end of the second resistor is grounded.

[0009] Furthermore, an overcurrent protection resistor is electrically connected between the field effect tube and the second resistor, and one end of the overcurrent protection resistor is electrically connected to a chip, the CS end of the chip is electrically connected to one end of the overcurrent protection resistor, and the GATE end of the chip is electrically connected to one side of the field effect tube.

[0010] Furthermore, one side of the overcurrent protection resistor is electrically connected to a temperature detection resistor, and one end of the temperature detection resistor is electrically connected to an overtemperature protection adjustment resistor, one end of the overtemperature protection adjustment resistor is electrically connected to a fifth diode, and one end of the fifth diode is electrically connected to a second transformer, and one end of the second transformer is grounded.

[0011] The utility model provides a circuit for realizing power supply temperature protection, which has the advantages that: the utility model adopts a current sampling angle tube of an ordinary chip, and adds capacitors, resistors, diodes and field effect tubes to realize power supply temperature protection, reduces dependence on dedicated chips, and improves the practicality of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art 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.

[0013] Figure 1 This is a power supply temperature protection circuit diagram of the utility model;

[0014] Figure 2 For the utility model Figure 1 A magnified schematic diagram of the middle A area;

[0015] Figure 3 For the utility model Figure 1 A magnified schematic diagram of the middle B area;

[0016] In the figure: 1. first diode; 2. second diode; 3. first glass capacitor; 4. first resistor; 5. protection capacitor; 6. third diode; 7. first transformer; 8. fourth diode; 9. second glass capacitor; 10. field effect transistor; 11. second resistor; 12. overcurrent protection resistor; 13. temperature detection resistor; 14. chip; 15. overtemperature protection adjustment resistor; 16. fifth diode; 17. second transformer; 18. sixth diode; 19. seventh diode. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment 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.

[0018] See also Figure 1-3 , the utility model provides an embodiment: a circuit for realizing power supply temperature protection, including a first diode 1, the first diode 1 and the second diode 2 are connected in parallel, and the sixth diode 18 and the seventh diode 19 are connected in parallel, the first diode 1, the second diode 2, the sixth diode 18 and the seventh diode 19 are all electrically connected to the voltage output terminal VIN, the first diode 1 and the second diode 2 are electrically connected to the first glass capacitor 3, and the first glass capacitor 3 is electrically connected to the sixth diode 18 and the seventh diode 19, one end of the first glass capacitor 3 is grounded, one end of the first glass capacitor 3 is electrically connected to the first row resistor 4 and the protection capacitor 5, and the protection capacitor 5 is electrically connected to the third diode 6, one end of the third diode 6 is connected in parallel with the first transformer 7, one side of the first transformer 7 is electrically connected to the fourth diode 8, and one side of the fourth diode 8 is electrically connected to the second glass capacitor 9, one side of the second glass capacitor 9 is electrically connected to the first transformer 7, and one side of the first transformer 7 is electrically connected to the field The field effect tube 10 is electrically connected to a second resistor array 11 at one end of the field effect tube 10, and one end of the second resistor array 11 is grounded. An overcurrent protection resistor 12 is electrically connected between the field effect tube 10 and the second resistor array 11, and one end of the overcurrent protection resistor 12 is electrically connected to a chip 14, a CS end of the chip 14 is electrically connected to one end of the overcurrent protection resistor 12, and a GATE end of the chip 14 is electrically connected to one side of the field effect tube 10, one side of the overcurrent protection resistor 12 is electrically connected to a temperature detection resistor 13, and one end of the temperature detection resistor 13 is electrically connected to an overtemperature protection regulating resistor 15, one end of the overtemperature protection regulating resistor 15 is electrically connected to a fifth diode 16, and one end of the fifth diode 16 is electrically connected to a second transformer 17, and one end of the second transformer 17 is grounded, which is conducive to the installation of the temperature detection resistor 13, the overtemperature protection regulating resistor 15, the overcurrent protection resistor 12 and the field effect tube 10, thereby improving the effect of power supply temperature protection, effectively solving the dependence on the dedicated chip 14, and improving the practicality of the equipment.

[0019] Working principle: During use, the utility model supplies power to the first diode 1, the second diode 2, the sixth diode 18 and the seventh diode 19 through the voltage output terminal VIN. When the over-temperature protection is triggered, the NTC resistor: Where V CS，OTP The over-temperature protection threshold voltage of the controller CS pin is 1V. When it is higher than 1V, the over-temperature protection is triggered. 0 The output voltage is 24V, V D1 The diode voltage drop is 0.7V, N A The number of turns of the auxiliary winding is 7Ts, N S The secondary winding turns are 10Ts, R OCPC The overcurrent protection resistor 12 has a resistance of 1kΩ, R ADJThe over-temperature protection adjustment resistor 15 has a resistance of 3.16 kΩ, R NTC The NTC resistor for temperature detection improves the effect of power supply temperature protection by installing the temperature detection resistor 13, the over-temperature protection adjustment resistor 15, the over-current protection resistor 12 and the field effect transistor 10, and effectively reduces the dependence on the dedicated chip 14.

[0020] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0022] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A circuit for implementing power supply temperature protection, comprising a first diode (1), characterized in that: The first diode (1) and the second diode (2) are connected in parallel, and the sixth diode (18) and the seventh diode (19) are connected in parallel, and the first diode (1), the second diode (2), the sixth diode (18) and the seventh diode (19) are all electrically connected to the voltage output terminal VIN.

2. A circuit for implementing power supply temperature protection according to claim 1, characterized in that: One end of the first diode (1) and the second diode (2) is electrically connected to a first glass capacitor (3), and one end of the first glass capacitor (3) is electrically connected to a sixth diode (18) and a seventh diode (19), and one end of the first glass capacitor (3) is grounded.

3. A circuit for implementing power supply temperature protection according to claim 2, characterized in that: One end of the first glass capacitor (3) is electrically connected to the first resistor (4) and the protection capacitor (5), and one end of the protection capacitor (5) is electrically connected to the third diode (6), and one end of the third diode (6) is connected in parallel with the first transformer (7).

4. A circuit for implementing power supply temperature protection according to claim 3, characterized in that: One side of the first transformer (7) is electrically connected to a fourth diode (8), and one side of the fourth diode (8) is electrically connected to a second glass capacitor (9), and one side of the second glass capacitor (9) is electrically connected to one side of the first transformer (7).

5. A circuit for implementing power supply temperature protection according to claim 4, characterized in that: One side of the first transformer (7) is electrically connected to a field effect tube (10), and one end of the field effect tube (10) is electrically connected to a second resistor (11), and one end of the second resistor (11) is grounded.

6. A circuit for implementing power supply temperature protection according to claim 5, characterized in that: An overcurrent protection resistor (12) is electrically connected between the field effect tube (10) and the second resistor array (11), and one end of the overcurrent protection resistor (12) is electrically connected to a chip (14), a CS end of the chip (14) is electrically connected to one end of the overcurrent protection resistor (12), and a GATE end of the chip (14) is electrically connected to one side of the field effect tube (10).

7. A circuit for implementing power supply temperature protection according to claim 6, characterized in that: One side of the overcurrent protection resistor (12) is electrically connected to a temperature detection resistor (13), and one end of the temperature detection resistor (13) is electrically connected to an overtemperature protection adjustment resistor (15), one end of the overtemperature protection adjustment resistor (15) is electrically connected to a fifth diode (16), and one end of the fifth diode (16) is electrically connected to a second transformer (17), and one end of the second transformer (17) is grounded.

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