CN215646156U - Protection circuit, switching power supply and electronic equipment - Google Patents
Protection circuit, switching power supply and electronic equipment Download PDFInfo
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- CN215646156U CN215646156U CN202121946302.XU CN202121946302U CN215646156U CN 215646156 U CN215646156 U CN 215646156U CN 202121946302 U CN202121946302 U CN 202121946302U CN 215646156 U CN215646156 U CN 215646156U
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Abstract
The utility model discloses a protection circuit, a switching power supply and electronic equipment, and belongs to the field of circuits. The protection circuit comprises a driving module, a detection module, a control module and a power supply chip; the driving module is connected with the detection module, and the control module is respectively connected with the detection module and the power supply chip; the driving module is used for outputting a driving signal according to a first input signal of an external power supply, the detection module is used for receiving the driving signal and outputting a detection signal according to the driving signal, the control module is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip is changed through the control signal so as to perform under-voltage protection on the power supply chip. The protection circuit can change the output state of the power supply chip when the power supply chip works in an undervoltage state, realize undervoltage protection on the power supply chip and improve the safety in the working process of the circuit.
Description
Technical Field
The utility model relates to the field of circuits, in particular to a protection circuit, a switching power supply and electronic equipment.
Background
Among the present integrated circuit, because supply voltage's unstability, the power chip often can work under the undervoltage condition, and when undervoltage condition during operation, the input current of power chip can increase to lead to the loss increase of power chip, make power chip have impaired problem. Therefore, how to provide a protection circuit that can protect the power chip when the power chip is under-voltage is a problem to be solved urgently.
SUMMERY OF THE UTILITY MODEL
The present invention is directed to solving at least one of the problems of the prior art. Therefore, the utility model provides a protection circuit which can perform under-voltage protection on a power supply chip and improve the safety of the circuit in the working process.
The utility model also provides a switching power supply with the protection circuit.
The utility model also provides electronic equipment with the switching power supply.
The protection circuit comprises a driving module, a detection module, a control module and a power supply chip;
the driving module is connected with the detection module, and the control module is respectively connected with the detection module and the power supply chip;
the driving module is used for outputting a driving signal according to a first input signal of an external power supply, the detection module is used for receiving the driving signal and outputting a detection signal according to the driving signal, and the control module is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip is changed through the control signal so as to perform under-voltage protection on the power supply chip.
The protection circuit provided by the embodiment of the utility model at least has the following beneficial effects: the protection circuit outputs a driving signal according to a first input signal of an external power supply through the driving module, the detection module is used for receiving the driving signal and outputting a detection signal according to the driving signal, the control module is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip is changed through the control signal.
According to some embodiments of the utility model, the driving module comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor;
the first end of the first resistor is connected with the first input end of the external power supply, and the second end of the first resistor is connected with the first end of the second resistor;
the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is connected with the first end of the third resistor;
the first end of the third resistor is connected with the second end of the second resistor, and the second end of the third resistor is respectively connected with the first end of the fourth resistor and the first end of the fifth resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, a first end of the fifth resistor and a first end of the first capacitor respectively, and a second end of the fourth resistor is connected with a first end of the second capacitor;
a first end of the fifth resistor is respectively connected with a second end of the third resistor, a first end of the fourth resistor and a first end of the first capacitor, and a second end of the fifth resistor is grounded;
the first end of the first capacitor is respectively connected with the second end of the third resistor, the first end of the fourth resistor and the first end of the fifth resistor, and the second end of the first capacitor is grounded;
and the first end of the second capacitor is connected with the second end of the fourth resistor, and the second end of the second capacitor is grounded.
According to some embodiments of the utility model, the detection module comprises a voltage regulation triode, a sixth resistor and a diode;
the first end of the triode for stabilizing voltage is connected with the second end of the fourth resistor and the first end of the second capacitor, the second end of the triode for stabilizing voltage is connected with the first end of the sixth resistor, and the third end of the triode for stabilizing voltage is grounded;
the first end of the sixth resistor is connected with the second end of the voltage-stabilizing triode, and the second end of the sixth resistor is connected with the cathode of the diode;
and the anode of the diode is connected with the second input end of the external power supply, and the cathode of the diode is connected with the second end of the sixth resistor.
According to some embodiments of the utility model, the control module comprises a zener diode and a field effect transistor;
the first end of the voltage stabilizing diode is respectively connected with the first end of the sixth resistor and the second end of the voltage stabilizing triode, the second end of the voltage stabilizing diode is connected with the grid electrode of the field effect transistor, and the third end of the voltage stabilizing diode is connected with the grid electrode of the field effect transistor;
the grid electrode of the field effect tube is respectively connected with the second end of the voltage stabilizing diode and the third end of the voltage stabilizing diode, the drain electrode of the field effect tube is connected with the voltage feedback input end of the power supply chip, and the source electrode of the field effect tube is grounded.
According to some embodiments of the utility model, the control module further comprises a seventh resistor;
the first end of the seventh resistor is respectively connected with the second end of the voltage stabilizing diode, the third end of the voltage stabilizing diode and the grid electrode of the field effect transistor, and the second end of the seventh resistor is grounded.
According to some embodiments of the utility model, the control module further comprises a third capacitor;
the first end of the third capacitor is respectively connected with the second end of the voltage stabilizing diode, the third end of the voltage stabilizing diode, the grid of the field effect transistor and the first end of the seventh resistor, and the second end of the third capacitor is grounded.
The switching power supply according to the second aspect of the embodiment of the utility model comprises the protection circuit according to the first aspect of the embodiment.
The switching power supply provided by the embodiment of the utility model has at least the following beneficial effects: the switch power supply adopts the protection circuit to output a driving signal according to a first input signal of an external power supply through the driving module, the detection module is used for receiving the driving signal and outputting a detection signal according to the driving signal, the control module is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip is changed through the control signal, so that the output state of the power supply chip can be changed when the power supply chip works in an undervoltage state, the undervoltage protection of the power supply chip is realized, and the safety in the working process of the circuit is improved.
An electronic device according to an embodiment of a third aspect of the utility model comprises the switching power supply according to the embodiment of the second aspect.
According to the electronic equipment provided by the embodiment of the utility model, at least the following beneficial effects are achieved: the electronic equipment adopts the switch power supply to output the driving signal according to the first input signal of the external power supply through the driving module, the detection module is used for receiving the driving signal and outputting the detection signal according to the driving signal, the control module is used for receiving the detection signal and outputting the control signal according to the detection signal and the second input signal of the external power supply, and the output state of the power chip is changed through the control signal, so that the output state of the power chip can be changed when the power chip works in an undervoltage state, the undervoltage protection of the power chip is realized, and the safety in the working process of the circuit is improved.
Additional aspects and advantages of the utility model will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the utility model.
Drawings
The utility model is further described with reference to the following figures and examples, in which:
FIG. 1 is a block diagram of a protection circuit according to an embodiment of the present invention;
fig. 2 is a circuit diagram of a protection circuit according to another embodiment of the utility model.
Reference numerals: 100. a drive module; 200. a detection module; 300. a control module; 400. and a power supply chip.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.
In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper, lower, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.
In the description of the present invention, the meaning of a plurality is one or more, the meaning of a plurality is two or more, and the above, below, exceeding, etc. are understood as excluding the present numbers, and the above, below, within, etc. are understood as including the present numbers. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.
In the description of the present invention, reference to the description of the terms "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
In a first aspect, referring to fig. 1 and 2, a protection circuit according to an embodiment of the present invention includes a driving module 100, a detection module 200, a control module 300, and a power chip 400; the driving module 100 is connected with the detection module 200, and the control module 300 is respectively connected with the detection module 200 and the power chip 400; the driving module 100 is configured to output a driving signal according to a first input signal of an external power supply, the detecting module 200 is configured to receive the driving signal and output a detecting signal according to the driving signal, and the control module 300 is configured to receive a detecting signal and output a control signal according to the detecting signal and a second input signal of the external power supply, and change an output state of the power chip 400 according to the control signal to perform under-voltage protection on the power chip 400. During the operation of the circuit, the driving module 100 receives a first input signal HV of the external power supply, where the first input signal HV of the external power supply is a first direct current signal obtained by rectifying an alternating current signal. The driving module 100 outputs a driving signal to the detecting module 200 according to the first input signal HV; the detection module 200 receives the driving signal, compares the received driving signal with a first preset voltage threshold, and outputs the comparison result to the control module 300 through the detection signal; the control module 300 receives the detection signal and outputs a control signal according to the detection signal and a second input signal VCC of the external power supply, where it should be noted that the second input signal VCC of the external power supply is a second direct current signal. The output state of the power supply chip 400 can be changed through the control signal, so that the under-voltage protection of the power supply chip 400 is realized, and the safety in the working process of the circuit is improved.
Referring to fig. 2, in some embodiments, the driving module 100 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a first capacitor C1, and a second capacitor C2; a first end of the first resistor R1 is connected with a first input end HV of an external power supply, and a second end of the first resistor R1 is connected with a first end of the second resistor R2; a first end of the second resistor R2 is connected with a second end of the first resistor R1, and a second end of the second resistor R2 is connected with a first end of the third resistor R3; a first end of the third resistor R3 is connected with a second end of the second resistor R2, and a second end of the third resistor R3 is respectively connected with a first end of the fourth resistor R4 and a first end of the fifth resistor R5; a first end of the fourth resistor R4 is connected to a second end of the third resistor R3, a first end of the fifth resistor R5 and a first end of the first capacitor C1, respectively, and a second end of the fourth resistor R4 is connected to a first end of the second capacitor C2; a first end of the fifth resistor R5 is respectively connected with a second end of the third resistor R3, a first end of the fourth resistor R4 and a first end of the first capacitor C1, and a second end of the fifth resistor R5 is grounded; a first end of the first capacitor C1 is connected to the second end of the third resistor R3, the first end of the fourth resistor R4 and the first end of the fifth resistor R5, respectively, and a second end of the first capacitor C1 is grounded; the first end of the second capacitor C2 is connected to the second end of the fourth resistor R4, and the second end of the second capacitor C2 is grounded. In the operation process of the circuit, a first input signal of the external power source is converted into a driving signal through the voltage division effect of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4 and the fifth resistor R5, and is output to the detection module 200.
Referring to fig. 2, in some embodiments, the detection module 200 includes a voltage regulation transistor ZD1, a sixth resistor R6, and a diode D1; a first end of the voltage-stabilizing triode ZD1 is connected with a second end of the fourth resistor R4 and a first end of the second capacitor C2, a second end of the voltage-stabilizing triode ZD1 is connected with a first end of the sixth resistor R6, and a third end of the voltage-stabilizing triode ZD1 is grounded; a first end of the sixth resistor R6 is connected to the second end of the zener transistor ZD1, and a second end of the sixth resistor R6 is connected to the cathode of the diode D1; an anode of the diode D1 is connected to the second input terminal VCC of the external power source, and a cathode of the diode D1 is connected to the second terminal of the sixth resistor R6. In the working process of the circuit, the zener triode ZD1 receives the driving signal, when the voltage value of the driving signal is greater than the first preset voltage threshold, the zener triode ZD1 is turned on, otherwise, when the voltage value of the driving signal is less than the first preset voltage threshold, the zener triode ZD1 is turned off. Specifically, the zener transistor ZD1 may be an AZ432 zener transistor ZD1, and the first preset voltage threshold may be 1.25V, and it should be noted that in some other embodiments, other types of zener transistors ZD1 may also be used, which is not limited thereto. In addition, the sixth resistor R6 plays a role in limiting current, and the diode D1 can determine the current flowing direction, so that the stability of the circuit in the working process is effectively improved.
Referring to fig. 2, in some embodiments, the control module 300 includes a zener diode ZD2 and a fet Q1; a first end of the zener diode ZD2 is connected to a first end of the sixth resistor R6 and a second end of the zener triode ZD1 respectively, a second end of the zener diode ZD2 is connected to the gate of the field-effect transistor Q1, and a third end of the zener diode ZD2 is connected to the gate of the field-effect transistor Q1; the grid of the field effect transistor Q1 is connected to the second terminal of the zener diode ZD2 and the third terminal of the zener diode ZD2 respectively, the drain of the field effect transistor Q1 is connected to the voltage feedback input terminal FB of the power chip 400, and the source of the field effect transistor Q1 is grounded. In the working process of the circuit, when the voltage value of the driving signal is greater than the first preset voltage threshold value, so that the voltage-stabilizing triode ZD1 is turned on, the zener diode ZD2 is turned off, and therefore the field-effect transistor Q1 is also in a turned-off state, and the voltage of the voltage feedback input terminal FB of the power chip 400 is unchanged; when the voltage value of the driving signal is smaller than the first preset voltage threshold value and the zener diode ZD1 is turned off, the second input terminal VCC of the external power supply turns on the zener diode ZD2, so the field effect transistor Q1 is also in a conducting state, the voltage feedback input terminal FB of the power chip 400 is turned on to ground, the voltage of the voltage feedback input terminal FB is pulled low and is smaller than the second preset voltage threshold value, the power chip 400 receives that the voltage of the voltage feedback input terminal FB is smaller than the second preset voltage threshold value and is controlled to restart, and after the restart, if the voltage of the voltage feedback input terminal FB received by the power chip 400 is still smaller than the second preset voltage threshold value, the power chip 400 is controlled to restart again, so as to circulate. By the mode, the power supply chip 400 can be restarted when the power supply chip 400 works in an undervoltage state, so that the power supply chip 400 is protected, and the safety of the circuit in the working process is improved.
Referring to fig. 2, in some embodiments, the control module 300 further includes a seventh resistor R7, a first terminal of the seventh resistor R7 is connected to the second terminal of the zener diode ZD2, the third terminal of the zener diode ZD2 and the gate of the fet Q1, respectively, and a second terminal of the seventh resistor R7 is grounded.
Referring to fig. 2, in some embodiments, the control module 300 further includes a third capacitor C3, the first terminal of the third capacitor C3 is connected to the second terminal of the zener diode ZD2, the third terminal of the zener diode ZD2, the gate of the fet Q1 and the first terminal of the seventh resistor R7, respectively, and the second terminal of the third capacitor C3 is grounded. When the circuit stops working, the electric quantity of the third capacitor C3 can be quickly discharged to the ground through the seventh resistor R7, and the working reliability of the circuit is improved.
In a second aspect, the present invention further provides a switching power supply, including the protection circuit shown in the first aspect.
The protection circuit of the switching power supply adopting the above embodiment can output a driving signal according to a first input signal of an external power supply through the driving module 100, the detection module 200 is used for receiving the driving signal and outputting a detection signal according to the driving signal, the control module 300 is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip 400 is changed through the control signal, so that the output state of the power supply chip 400 can be changed when the power supply chip 400 works in an under-voltage state, the under-voltage protection of the power supply chip 400 is realized, and the safety of the circuit in the working process is improved.
In a third aspect, the present invention further provides an electronic device, including the switching power supply shown in the second aspect.
The switching power supply adopting the above embodiment of the electronic device can output the driving signal according to the first input signal of the external power supply through the driving module 100, the detection module 200 is configured to receive the driving signal and output the detection signal according to the driving signal, the control module 300 is configured to receive the detection signal and output the control signal according to the detection signal and the second input signal of the external power supply, and the output state of the power chip 400 is changed through the control signal, so that the output state of the power chip 400 can be changed when the power chip 400 operates in the under-voltage state, the under-voltage protection of the power chip 400 is realized, and the safety of the circuit in the operating process is improved.
The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present invention. Furthermore, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.
Claims (8)
1. The protection circuit is characterized by comprising a driving module, a detection module, a control module and a power supply chip;
the driving module is connected with the detection module, and the control module is respectively connected with the detection module and the power supply chip;
the driving module is used for outputting a driving signal according to a first input signal of an external power supply, the detection module is used for receiving the driving signal and outputting a detection signal according to the driving signal, and the control module is used for receiving the detection signal and outputting a control signal according to the detection signal and a second input signal of the external power supply, and the output state of the power supply chip is changed through the control signal so as to perform under-voltage protection on the power supply chip.
2. The protection circuit according to claim 1, wherein the driving module comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a first capacitor and a second capacitor;
the first end of the first resistor is connected with the first input end of the external power supply, and the second end of the first resistor is connected with the first end of the second resistor;
the first end of the second resistor is connected with the second end of the first resistor, and the second end of the second resistor is connected with the first end of the third resistor;
the first end of the third resistor is connected with the second end of the second resistor, and the second end of the third resistor is respectively connected with the first end of the fourth resistor and the first end of the fifth resistor;
a first end of the fourth resistor is connected with a second end of the third resistor, a first end of the fifth resistor and a first end of the first capacitor respectively, and a second end of the fourth resistor is connected with a first end of the second capacitor;
a first end of the fifth resistor is respectively connected with a second end of the third resistor, a first end of the fourth resistor and a first end of the first capacitor, and a second end of the fifth resistor is grounded;
the first end of the first capacitor is respectively connected with the second end of the third resistor, the first end of the fourth resistor and the first end of the fifth resistor, and the second end of the first capacitor is grounded;
and the first end of the second capacitor is connected with the second end of the fourth resistor, and the second end of the second capacitor is grounded.
3. The protection circuit of claim 2, wherein the detection module comprises a voltage-regulator transistor, a sixth resistor, and a diode;
the first end of the triode for stabilizing voltage is connected with the second end of the fourth resistor and the first end of the second capacitor, the second end of the triode for stabilizing voltage is connected with the first end of the sixth resistor, and the third end of the triode for stabilizing voltage is grounded;
the first end of the sixth resistor is connected with the second end of the voltage-stabilizing triode, and the second end of the sixth resistor is connected with the cathode of the diode;
and the anode of the diode is connected with the second input end of the external power supply, and the cathode of the diode is connected with the second end of the sixth resistor.
4. The protection circuit of claim 3, wherein the control module comprises a zener diode and a field effect transistor;
the first end of the voltage stabilizing diode is respectively connected with the first end of the sixth resistor and the second end of the voltage stabilizing triode, the second end of the voltage stabilizing diode is connected with the grid electrode of the field effect transistor, and the third end of the voltage stabilizing diode is connected with the grid electrode of the field effect transistor;
the grid electrode of the field effect tube is respectively connected with the second end of the voltage stabilizing diode and the third end of the voltage stabilizing diode, the drain electrode of the field effect tube is connected with the voltage feedback input end of the power supply chip, and the source electrode of the field effect tube is grounded.
5. The protection circuit of claim 4, wherein the control module further comprises a seventh resistor;
the first end of the seventh resistor is respectively connected with the second end of the voltage stabilizing diode, the third end of the voltage stabilizing diode and the grid electrode of the field effect transistor, and the second end of the seventh resistor is grounded.
6. The protection circuit of claim 5, wherein the control module further comprises a third capacitor;
the first end of the third capacitor is respectively connected with the second end of the voltage stabilizing diode, the third end of the voltage stabilizing diode, the grid of the field effect transistor and the first end of the seventh resistor, and the second end of the third capacitor is grounded.
7. Switching power supply, characterized in that it comprises a protection circuit according to any of claims 1 to 6.
8. Electronic device, characterized in that it comprises a switched-mode power supply as claimed in claim 7.
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CN202121946302.XU CN215646156U (en) | 2021-08-18 | 2021-08-18 | Protection circuit, switching power supply and electronic equipment |
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CN202121946302.XU CN215646156U (en) | 2021-08-18 | 2021-08-18 | Protection circuit, switching power supply and electronic equipment |
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