Overcurrent protection circuit of bidirectional power supply

Abstract

The utility model relates to an overcurrent protection circuit of a bidirectional power supply. The overcurrent protection circuit of the bidirectional power supply comprises a power supply input module, a protection module and an output module, the protection module comprises a resistor R1, a resistor R3, a resistor R11, a comparator U1A and a comparator U1B, the resistor R1 is electrically connected with the first end of the resistor R3, the first end of the resistor R3 is further electrically connected with the comparator U1A, the second end of the resistor R3 is electrically connected with the power supply input module, and the output module is electrically connected with the output module. The first end of the resistor R11 is electrically connected with the second end of the resistor R3 and the comparator U1B, and the second end of the resistor R11 is grounded; and the output module is electrically connected with the comparator U1A and the comparator U1B respectively. According to the scheme provided by the invention, the overcurrent protection circuit can be arranged for the bidirectional power supply, so that when the bidirectional power supply is overloaded or short-circuited, the power supply circuit can be turned off in time, and the electric appliance is protected.

Description

TECHNICAL FIELD

[0001] The utility model relates to power supply technical field especially is related to a kind of overcurrent protection circuit of bidirectional power supply. BACKGROUND

[0002] Bidirectional power supply is a kind of power supply that can be used as external load, and can receive electric energy under certain conditions, process external input electric energy.

[0003] In related art, overcurrent protection is not set for bidirectional power supply, so when bidirectional power supply appears short circuit or overload, the current output will exceed its rated current, so as to burn down electric appliance. INVENTION CONTENTS

[0004] The utility model discloses a kind of overcurrent protection circuit of bidirectional power supply, which can set overcurrent protection circuit to bidirectional power supply, so as to when bidirectional power supply appears overload or short circuit, power supply circuit can be turned off in time, protect electric appliance.

[0005] The utility model discloses a kind of overcurrent protection circuit of bidirectional power supply, which can set overcurrent protection circuit to bidirectional power supply, so as to when bidirectional power supply appears overload or short circuit, power supply circuit can be turned off in time, protect electric appliance.

[0006] The first aspect of the application provides an overcurrent protection circuit of bidirectional power supply, comprising: a power input module; a protection module comprising resistors R1, R3, R11, comparators U1A and U1B, the first end of the resistor R1 is electrically connected with the resistor R3, the first end of the resistor R3 is also electrically connected with the comparator U1A, the second end of the resistor R3 is electrically connected with the power input module, the first end of the resistor R11 is electrically connected with the second end of the resistor R3 and the comparator U1B, and the second end of the resistor R11 is grounded; an output module, which is electrically connected with the comparators U1A and U1B respectively.

[0007] The protection module further comprises a resistor R6 and a capacitor C4, the first end of the resistor R6 is electrically connected with the power input module, the first end of the capacitor C4 is electrically connected with the second end of the resistor R6, the second end of the capacitor C4 is grounded, and the second end of the resistor R6 is also electrically connected with the comparators U1A and U1B respectively.

[0008] The protection module further comprises a capacitor C2 and a capacitor C7, the first end of the capacitor C2 is electrically connected with the first end of the resistor R3, the second end of the capacitor C2 is grounded, the first end of the capacitor C7 is electrically connected with the second end of the resistor R3, and the second end of the capacitor C7 is grounded.

[0009] The power input module comprises an operational amplifier U2, and the operational amplifier U2 is electrically connected with a first end of the resistor R6.

[0010] The power input module further comprises a differential unit, the differential unit comprises a resistor R5, a capacitor C1 and a resistor R2, a first end of the resistor R5 is electrically connected with a first end of the capacitor C1, a second end of the capacitor C1 is electrically connected with a first end of the resistor R2, and a second end of the resistor R2 is electrically connected with the operational amplifier U2.

[0011] The power input module further comprises a signal amplification unit, the signal amplification unit comprises a resistor R9, a capacitor C6 and a resistor R10, a first end of the resistor R9 is electrically connected with a first end of the capacitor C6, a first end of the capacitor C6 is electrically connected with a first end of the resistor R10, and a second end of the resistor R10 is electrically connected with the operational amplifier U2.

[0012] The power input module further comprises a filter unit, the filter unit comprises a resistor R4, a resistor R8 and a capacitor C3, a first end of the resistor R4 is electrically connected with a second end of the resistor R5 and a first end of the capacitor C3 respectively, and a first end of the resistor R8 is electrically connected with a second end of the resistor R9 and a second end of the capacitor C3 respectively.

[0013] The power input module further comprises a sampling resistor RS1, a first end of the sampling resistor RS1 is electrically connected with a second end of the resistor R4, and a second end of the sampling resistor RS1 is electrically connected with a second end of the resistor R8.

[0014] The output module comprises a resistor R7, and a first end of the resistor R7 is electrically connected with the comparator U1A and the comparator U1B respectively.

[0015] The output module further comprises a capacitor C5, a first end of the capacitor C5 is electrically connected with a second end of the resistor R7, and a second end of the capacitor C5 is grounded.

[0016] Compared with the prior art, the power input module has at least the following advantages:

[0017] When the bidirectional power supply is overloaded or short-circuited, the resistor R1, the resistor R3 and the resistor R11 are provided, the three resistors are adjustable voltage dividing resistors, the comparator U1A and the comparator U1B output low level to an external main control chip by adjusting the resistance value, so that the main control chip closes the power supply circuit, thereby forming protection for the electric appliance. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme of the embodiments of the utility model, the following will be briefly introduced the drawings needed to be used in the embodiments.

[0019] Figure 1 Figure 1 is a function module diagram of the overcurrent protection circuit of the bidirectional power supply in an embodiment of the present application.

[0020] Figure 2 Figure 1 is a function module diagram of the overcurrent protection circuit of the bidirectional power supply in an embodiment of the present application. DETAILED DESCRIPTION

[0021] Embodiments of the present application will be described in more detail with reference to the drawings. Although embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided so that the present application is more thoroughly and completely conveyed to those skilled in the art, and the scope of the present application is fully conveyed to those skilled in the art.

[0022] It should be understood that although the terms "first", "second", "third", etc. are used to describe various information in the present application, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information without departing from the scope of the present application. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0023] Unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected or integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] The bidirectional power supply is a kind of power supply that can supply power to external load, and can receive electric energy under certain conditions to process external input electric energy. At present, the overcurrent protection is not set for the bidirectional power supply, and thus when the bidirectional power supply appears short circuit or overload, the output current of the bidirectional power supply will exceed the rated current, thereby burning the electric appliance.

[0025] In view of the above problems, the present application provides an overcurrent protection circuit for bidirectional power supply, which can set an overcurrent protection circuit for bidirectional power supply, so as to timely shut down the power supply circuit when the bidirectional power supply appears overload or short circuit, and protect the electric appliance.

[0026] The technical solutions of the embodiments of the present application are described in detail below with reference to the drawings.

[0027] Please refer to Figure 1 and Figure 2 A kind of overcurrent protection circuit of bidirectional power supply, comprising: power input module 100, protection module 200 and output module 300, protection module 200 includes resistance R1, resistance R3, resistance R11, comparator U1A and comparator U1B, resistance R1 with the first end of resistance R3 is electrically connected, the first end of resistance R3 is also electrically connected with comparator U1A, the second end of resistance R3 is electrically connected with power input module, the first end of resistance R11 is electrically connected with the second end of resistance R3 and comparator U1B, the second end of resistance R11 is grounded;Output module 300 is electrically connected with comparator U1A and comparator U1B respectively.

[0028] It needs to be explained that power input module 100 is used for external bidirectional power supply, when overload or short circuit occurs in bidirectional power supply, by setting resistance R1, resistance R3 and resistance R11, the three resistances are adjustable voltage dividing resistors, by adjusting resistance value, so that comparator U1A and comparator U1B output low level to external master control chip, to make master control chip close power supply circuit, thereby forming protection to electric appliance.

[0029] It also needs to be explained that the maximum resistance value of resistance R1 is 2K ohm, the maximum resistance value of resistance R3 is 10K ohm, and the maximum resistance value of resistance R11 is 2K ohm. For example, the rated output current of bidirectional power supply is 80A, when overload or short circuit occurs, the output of bidirectional power supply after amplification by operational amplifier U2 reaches 100A or more, and the rated current of electric appliance is 100A, therefore, by the resistance value of resistance R1, resistance R3 and resistance R11, when greater than 100A, comparator U1A and comparator U1B output low level to master control chip, and master control chip turns off power supply circuit.

[0030] Further, when the voltage of the 3rd pin of comparator U1A is less than the voltage of the 2nd pin, low level is output, and when the voltage of the 5th pin of comparator U1B is less than the voltage of the 6th pin, low level is output. In addition, the voltage of OCR_A and OCR_B is 3V.

[0031] Please refer to Figure 2 In an embodiment, protection module 200 further includes resistance R6 and capacitor C4, the first end of resistance R6 is electrically connected with power input module, the first end of capacitor C4 is electrically connected with the second end of resistance R6, the second end of capacitor C4 is grounded, and the second end of resistance R6 is also electrically connected with comparator U1A and comparator U1B respectively.

[0032] It needs to be explained that resistance R6 is current limiting resistance, and capacitor C4 is filter capacitor.

[0033] Please refer to Figure 2 In an embodiment, the protection module 200 further comprises a capacitor C2 and a capacitor C7, a first end of the capacitor C2 is electrically connected with a first end of the resistor R3, a second end of the capacitor C2 is grounded, a first end of the capacitor C7 is electrically connected with a second end of the resistor R3, and a second end of the capacitor C7 is grounded.

[0034] It should be noted that the capacitor C2 and the capacitor C7 are filter capacitors.

[0035] Please refer to Figure 2 In an embodiment, the power input module 100 comprises an operational amplifier U2, and the operational amplifier U2 is electrically connected with a first end of the resistor R6.

[0036] It should be noted that the reference voltage of the operational amplifier U2 is 1.65V. The operational amplifier U2 is used for amplifying the voltage signal.

[0037] Please refer to Figure 2 In an embodiment, the power input module 100 further comprises a difference unit, and the difference unit comprises a resistor R5, a capacitor C1 and a resistor R2, a first end of the resistor R5 is electrically connected with a first end of the capacitor C1, a second end of the capacitor C1 is electrically connected with a first end of the resistor R2, and a second end of the resistor R2 is electrically connected with the operational amplifier U2.

[0038] It should be noted that the difference unit can ensure that the operational amplifier more accurately extracts the useful difference signal when processing the signal.

[0039] Please refer to Figure 2 In an embodiment, the power input module 100 further comprises a signal amplification unit, and the signal amplification unit comprises a resistor R9, a capacitor C6 and a resistor R10, a first end of the resistor R9 is electrically connected with a first end of the capacitor C6, a first end of the capacitor C6 is electrically connected with a first end of the resistor R10, and a second end of the resistor R10 is electrically connected with the operational amplifier U2.

[0040] It should be noted that the signal amplification unit is used for enhancing the signal strength and improving the quality of the signal.

[0041] Please refer to Figure 2 In an embodiment, the power input module 100 further comprises a filter unit, and the filter unit comprises a resistor R4, a resistor R8 and a capacitor C3, a first end of the resistor R4 is electrically connected with a second end of the resistor R5 and a first end of the capacitor C3 respectively, and a first end of the resistor R8 is electrically connected with a second end of the resistor R9 and a second end of the capacitor C3 respectively.

[0042] It should be noted that the filter power is used for filtering out the ripple in the circuit.

[0043] Please refer to Figure 2In an embodiment, the power input module 100 further comprises a sampling resistor RS1, a first end of the sampling resistor RS1 is electrically connected with the second end of the resistor R4, and a second end of the sampling resistor RS1 is electrically connected with the second end of the resistor R8.

[0044] It should be noted that the sampling resistor RS1 has a resistance of 0.001 ohm, so as to reduce power consumption. The sampling resistor RS1 is externally connected with a bidirectional power supply.

[0045] Referring to Figure 2 In an embodiment, the output module 300 comprises a resistor R7, a first end of the resistor R7 is electrically connected with the comparator U1A and the comparator U1B respectively.

[0046] It can be understood that the resistor R7 is a current-limiting resistor.

[0047] Referring to Figure 2 In an embodiment, the output module 300 further comprises a capacitor C5, a first end of the capacitor C5 is electrically connected with the second end of the resistor R7, and a second end of the capacitor C5 is grounded.

[0048] It can be understood that the capacitor C5 is a filter capacitor, and the filtered signal will be connected to the master chip through Iocp_NET.

[0049] The scheme of the present application has been described in detail above with reference to the drawings. In the above-described embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments. It should also be known by those skilled in the art that the actions and modules involved in the specification are not necessarily required by the present application. In addition, it can be understood that the steps in the method of the embodiments of the present application can be adjusted, combined and reduced in sequence according to actual needs, and the modules in the device of the embodiments of the present application can be combined, divided and reduced according to actual needs.

[0050] The above has described various embodiments of the present application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles, practical applications or improvements to the technology in the market of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A current foldback circuit for a bidirectional power supply, comprising: a first current foldback circuit for a first direction of current flow; and a second current foldback circuit for a second direction of current flow. The application relates to a power input module, a protection module and an output module. The protection module comprises a resistor R1, a resistor R3, a resistor R11, a comparator U1A and a comparator U1B, the first end of the resistor R1 is electrically connected with the first end of the resistor R3, the first end of the resistor R3 is also electrically connected with the comparator U1A, the second end of the resistor R3 is electrically connected with the power input module, the first end of the resistor R11 is electrically connected with the second end of the resistor R3 and the comparator U1B, and the second end of the resistor R11 is grounded. The output module is electrically connected with the comparator U1A and the comparator U1B respectively. The protection module further comprises a resistor R6 and a capacitor C4, the first end of the resistor R6 is electrically connected with the power input module, the first end of the capacitor C4 is electrically connected with the second end of the resistor R6, the second end of the capacitor C4 is grounded, and the second end of the resistor R6 is also electrically connected with the comparator U1A and the comparator U1B respectively.

2. The overcurrent protection circuit for a bidirectional power supply according to claim 1, wherein The protection module further comprises a capacitor C2 and a capacitor C7, the first end of the capacitor C2 is electrically connected with the first end of the resistor R3, the second end of the capacitor C2 is grounded, the first end of the capacitor C7 is electrically connected with the second end of the resistor R3, and the second end of the capacitor C7 is grounded.

3. The overcurrent protection circuit for a bidirectional power supply according to claim 1, wherein The power input module comprises an operational amplifier U2, and the operational amplifier U2 is electrically connected with the first end of the resistor R6.

4. The overcurrent protection circuit for a bidirectional power supply according to claim 2, wherein The power input module further comprises a differential unit, the differential unit comprises a resistor R5, a capacitor C1 and a resistor R2, the first end of the resistor R5 is electrically connected with the first end of the capacitor C1, the second end of the capacitor C1 is electrically connected with the first end of the resistor R2, and the second end of the resistor R2 is electrically connected with the operational amplifier U2.

5. The overcurrent protection circuit for a bidirectional power supply according to claim 4, wherein The power input module further comprises a signal amplification unit, the signal amplification unit comprises a resistor R9, a capacitor C6 and a resistor R10, the first end of the resistor R9 is electrically connected with the first end of the capacitor C6, the first end of the capacitor C6 is electrically connected with the first end of the resistor R10, and the second end of the resistor R10 is electrically connected with the operational amplifier U2.

6. The overcurrent protection circuit for a bidirectional power supply of claim 5, wherein, The power input module further comprises a filter unit, the filter unit comprises a resistor R4, a resistor R8 and a capacitor C3, the first end of the resistor R4 is electrically connected with the second end of the resistor R5 and the first end of the capacitor C3 respectively, and the first end of the resistor R8 is electrically connected with the second end of the resistor R9 and the second end of the capacitor C3 respectively.

7. The overcurrent protection circuit for a bidirectional power supply according to claim 6, wherein The power input module further comprises a sampling resistor RS1, the first end of the sampling resistor RS1 is electrically connected with the second end of the resistor R4, and the second end of the sampling resistor RS1 is electrically connected with the second end of the resistor R8.

8. The overcurrent protection circuit for a bidirectional power supply of claim 1, wherein, The output module comprises a resistor R7, and the first end of the resistor R7 is electrically connected with the comparator U1A and the comparator U1B respectively.

9. The overcurrent protection circuit for a bidirectional power supply of claim 1, wherein, The output module further comprises a capacitor C5, the first end of the capacitor C5 is electrically connected with the second end of the resistor R7, and the second end of the capacitor C5 is grounded.

10. The overcurrent protection circuit for a bidirectional power supply of claim 9, wherein, ​

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