Surge protection circuit, chip and electronic equipment

Abstract

The utility model provides a surge protection circuit, a chip and electronic equipment, and relates to the technical field of circuits. Comprising a switch unit and a voltage suppression unit, the input end of the switch unit is connected with a power supply; the output end of the switch unit is grounded; the first end of the voltage suppression unit is connected with a power supply, and the second end of the voltage suppression unit is connected with the control end of the switch unit; and when the voltage output by the power supply is greater than the voltage conduction threshold value of the voltage suppression unit, the voltage suppression unit outputs a high level signal to the control end of the switch unit, so that the switch unit is in a conduction state. In the embodiment of the utility model, the discharge of surge and the discharge of other forms of energy generated by the power supply are both carried out by the switch unit. The voltage suppression unit is only used for controlling the switch-on and switch-off of the switch unit and is not directly used for surge discharge. Therefore, the switch unit and the voltage suppression unit in the embodiment of the invention can be packaged in the same chip, so that the manufacturing cost and the area of the chip are reduced.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of circuit, and particularly relates to a surge protection circuit, a chip and an electronic device. BACKGROUND

[0002] Surge refers to an overload current (or voltage) far greater than the steady-state current (or voltage) of a power supply generated at the moment of power-on or in the case of abnormality. In order to avoid damage to components in an electronic device caused by surge, a surge protection circuit is usually provided in the electronic device.

[0003] The surge protection circuit in the related art is composed of a switching unit and a voltage suppression unit which are independent of each other. The voltage suppression unit is used to dissipate surge energy when surge occurs, and the switching unit is used to dissipate various forms of energy generated by the power supply according to a control signal, that is, both of them are energy dissipation units. Limited by the limitation of chip technology, the two energy dissipation units need to be packaged as two independent chips, which not only has high packaging cost, but also has large chip area due to low integration. UTILITY MODEL CONTENT

[0004] In order to overcome the problems in the related art, the present disclosure provides a surge protection circuit, a chip and an electronic device.

[0005] According to a first aspect of the embodiments of the present disclosure, a surge protection circuit is provided, comprising: a switching unit and a voltage suppression unit.

[0006] An input end of the switching unit is connected with a power supply, and an output end of the switching unit is grounded.

[0007] A first end of the voltage suppression unit is connected with the power supply, and a second end of the voltage suppression unit is connected with a control end of the switching unit.

[0008] When a voltage output by the power supply is greater than a voltage conduction threshold of the voltage suppression unit, the voltage suppression unit outputs a high-level signal to the control end of the switching unit, so that the switching unit is in a conduction state.

[0009] In some embodiments, the voltage suppression unit comprises: a diode and a first resistor.

[0010] A cathode of the diode is connected with the power supply, and an anode of the diode is connected with the control end of the switching unit.

[0011] A first end of the first resistor is connected with the anode of the diode, and a second end of the first resistor is grounded.

[0012] The voltage conduction threshold is a reverse breakdown voltage of the diode.

[0013] In some embodiments, the surge protection circuit further comprises a direct current protection unit;

[0014] The direct current protection unit is connected with the power supply and the control end of the switch unit respectively;

[0015] When the current output by the power supply passes through the direct current protection unit, the direct current protection unit outputs a high-level signal to the control end of the switch unit within a specified time length, so that the switch unit is in a conductive state.

[0016] In some embodiments, the direct current protection unit comprises a capacitor;

[0017] The first end of the capacitor is connected with the power supply, and the second end of the capacitor is connected with the control end of the switch unit.

[0018] In some embodiments, the direct current protection unit further comprises a second resistor;

[0019] The first end of the second resistor is connected with the second end of the capacitor, and the second end of the second resistor is grounded.

[0020] In some embodiments, the capacitor is a polar capacitor;

[0021] The first end of the capacitor is the positive electrode of the polar capacitor, and the second end of the capacitor is the negative electrode of the polar capacitor.

[0022] In some embodiments, the switch unit comprises a MOS tube;

[0023] The drain of the MOS tube is the input end of the switch unit, the source of the MOS tube is the output end of the switch unit, and the gate of the MOS tube is the control end of the switch unit.

[0024] According to a second aspect of the embodiments of the present disclosure, a surge protection chip is provided, comprising the surge protection circuit according to the first aspect.

[0025] According to a third aspect of the embodiments of the present disclosure, an electronic device is provided, comprising a negative temperature coefficient temperature measurement circuit, a processor, a power management integrated circuit, and the surge protection circuit according to the first aspect;

[0026] The negative temperature coefficient temperature measurement circuit is configured to detect the temperature of a power supply port of the electronic device.

[0027] The processor is connected with the negative temperature coefficient temperature measurement circuit and the power management integrated circuit respectively, and configured to send a control instruction to the power management integrated circuit according to the temperature of the power supply port.

[0028] The power management integrated circuit is connected with the control end of the switch unit in the surge protection circuit, and is used for controlling the conduction and cutoff of the switch unit according to the control instruction.

[0029] In some embodiments, a protection resistor is further arranged between the power management integrated circuit and the control end of the switch unit.

[0030] The technical scheme provided by the embodiments of the present disclosure can have the following beneficial effects:

[0031] The surge protection circuit provided by the embodiments of the present disclosure includes a switch unit and a voltage suppression unit. The input end of the switch unit is connected with a power supply, and the output end is grounded. The first end of the voltage suppression unit is connected with the power supply, and the second end is connected with the control end of the switch unit. When the voltage output by the power supply is greater than the voltage conduction threshold of the voltage suppression unit, the voltage suppression unit outputs a high-level signal to the control end of the switch unit, so that the switch unit is in a conduction state. In the embodiments of the present disclosure, whether it is the discharge of a surge or the discharge of other forms of energy generated by the power supply, it is performed by the switch unit. The voltage suppression unit is only used to control the conduction and cutoff of the switch unit, and is not directly used for surge discharge. Therefore, the switch unit and the voltage suppression unit in the embodiments of the present disclosure can be packaged in the same chip, thereby reducing the manufacturing cost and area of the chip. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A structure schematic diagram of a surge protection circuit in the embodiments of the present disclosure is shown.

[0033] Figure 2 A structure schematic diagram of another surge protection circuit in the embodiments of the present disclosure is shown.

[0034] Figure 3 A structure schematic diagram of an electronic device in the embodiments of the present disclosure is shown.

[0035] REFERENCE SIGNS:

[0036] 100 - switch unit; 101 - MOS tube; 200 - voltage suppression unit; 201 - diode; 202 - first resistor; 300 - driving circuit; 400 - direct current protection unit; 401 - capacitor; 402 - second capacitor; 510 - NTC temperature measurement circuit; 520 - processor; 530 - PMIC; 540 - surge protection circuit. DETAILED DESCRIPTION

[0037] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The following description is made with reference to the accompanying drawings in which like reference numerals refer to like elements, and the term "exemplary" is used herein to mean "serving as an example, instance, or illustration." The following description is not intended to limit the scope of the present disclosure, but is merely intended to describe the exemplary embodiments of the present disclosure.

[0038] In addition, the terms "first", "second", and the like used in the present disclosure are merely used to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

[0039] Figure 1 An embodiment of the present disclosure is shown, and a surge protection circuit is shown in the embodiment of the present disclosure, as shown in the figure, the surge protection circuit comprises a switching unit 100 and a voltage suppression unit 200. Figure 1

[0040] The input end of the switching unit 100 is connected with the power supply, and the output end of the switching unit 100 is grounded.

[0041] The first end of the voltage suppression unit 200 is connected with the power supply, and the second end of the voltage suppression unit 200 is connected with the control end of the switching unit 100.

[0042] When the voltage output by the power supply is greater than the voltage conduction threshold of the voltage suppression unit 200, the voltage suppression unit 200 outputs a high-level signal to the control end of the switching unit 100, so that the switching unit 100 is in a conduction state.

[0043] In some embodiments, the switching unit 100 can comprise a MOS tube 101. The drain of the MOS tube 101 is the input end of the switching unit 100, the source of the MOS tube 101 is the output end of the switching unit 100, and the gate of the MOS tube 101 is the control end of the switching unit 100.

[0044] In the case that the gate of the MOS tube 101 receives a high-level signal, the resistance between the drain and the source of the MOS tube 101 is approximately zero, the MOS tube 101 is conducted from the drain to the source, and the power supply is directly grounded through the MOS tube 101, so that the MOS tube 101 can discharge the surge generated by the power supply.

[0045] ​In some embodiments, the control end of the switch unit 100 can be connected with the driving circuit 300 outside the surge protection circuit while being controlled by the voltage suppression unit 200, so as to receive the control signal sent by the driving circuit 300. For example, in the case where the temperature of the power supply port of the electronic device is detected to be too high, the driving circuit 300 can send a high-level signal to the control end of the switch unit 100, so that the switch unit 100 is in a conducting state, thereby making the power supply inserted into the power supply port directly grounded through the switch unit 100. In this way, the power supply to the electronic device can be suspended, so as to cool the power supply port and prevent the power supply port from being damaged due to high temperature.

[0046] In some embodiments, the voltage suppression unit 200 can include a diode 201 and a first resistor 202. The cathode of the diode is connected with the power supply, and the anode of the diode 201 is connected with the control end of the switch unit 100. The first end of the first resistor 202 is connected with the anode of the diode, and the second end of the first resistor 202 is grounded.

[0047] Correspondingly, the voltage conducting threshold is the reverse breakdown voltage of the diode.

[0048] It can be understood that, in the case where the voltage output by the power supply is less than the reverse breakdown voltage of the diode 201, the diode 201 is cut off from the cathode to the anode, so as to suppress the voltage output by the power supply. At this time, the switch unit 100 is also in a cut-off state, so that the power supply can normally supply power to the electronic device.

[0049] In the case where the voltage output by the power supply is greater than the reverse breakdown voltage of the diode 201, the diode 201 is conducted from the cathode to the anode. Since the anode of the diode 201 is grounded through the first resistor 202, in the case where the diode 201 is conducted from the cathode to the anode, the anode of the diode 201 can provide a high-level signal to control the switch unit 100 to be in a conducting state, so that the switch unit 100 plays a role of discharging surge.

[0050] Please refer to Figure 2 In some embodiments, the surge protection circuit further includes a direct current protection unit 400. The direct current protection unit 400 is connected with the power supply and the control end of the switch unit 100, respectively. When the current output by the power supply passes through the direct current protection unit 400, the direct current protection unit 400 outputs a high-level signal to the control end of the switch unit 100 within a specified time length, so as to make the switch unit 100 in a conducting state.

[0051] Since the voltage of the surge can be less than the voltage turn-on threshold, the switch unit 100 cannot be triggered to turn on by the voltage suppression unit 200. In this case, the switch unit 100 can be triggered to turn on by the DC protection unit 400, so that the switch unit 100 can also discharge the surge or DC energy with a voltage less than the voltage turn-on threshold.

[0052] Exemplarily, the DC protection unit 400 can include a capacitor 401. A first end of the capacitor 401 can be connected to the power supply, and a second end of the capacitor 401 can be connected to the control end of the switch unit 100.

[0053] When the surge or DC energy output by the power supply passes through the capacitor 401, the capacitor 401 is in a charging state. In this case, assuming that the voltage suppression unit 200 is implemented by the diode 201 and the first resistor 202, the second end of the capacitor 401 can also be grounded through the first resistor 202 connected to the control end (anode of the diode 201) of the switch unit 100, so that the second end of the capacitor 401 can provide a high-level signal to control the switch unit 100 to be in a turn-on state, so that the switch unit 100 can also discharge the surge or DC energy with a lower voltage.

[0054] Exemplarily, the DC protection unit 400 can further include a second resistor 402. A first end of the second resistor 402 is connected to the second end of the DC protection unit 400, and a second end of the second resistor 402 is grounded.

[0055] The second resistor 402 can have two functions. One is to increase the potential of the second end of the capacitor 401 in the absence of the first resistor 202 in the voltage suppression unit 200, so that the second end of the capacitor 401 outputs a high-level signal capable of driving the switch unit 100. The other is that after the surge protection circuit including the switch unit 100 and the voltage suppression unit 200 has been packaged into a chip, if it is desired to additionally add the DC protection unit 400 on the basis of the chip, the second resistor 402 can be used to adjust the charging time of the capacitor 401, so as to adjust the time (the above-mentioned specified time) during which the DC protection unit 400 can drive the switch unit 100 to turn on.

[0056] Exemplarily, the capacitor 401 in the DC protection unit 400 can be a polarized capacitor. The first end of the capacitor 401 is the positive pole of the polarized capacitor, and the second end of the capacitor 401 is the negative pole of the polarized capacitor. That is, the positive pole of the polarized capacitor is connected to the power supply, and the negative pole is connected to the control end of the switch unit 100.

[0057] It can be understood that the polar capacitor can have a larger capacitance value, thereby appropriately prolonging the charging time of the capacitor 401, enabling the DC protection unit 400 to output a high-level signal for a longer time to drive the switch unit 100 to discharge the DC energy with a longer duration.

[0058] Based on the same concept, the present disclosure also provides a surge protection chip comprising the surge protection circuit described above. For the implementation of this embodiment, reference can be made to the implementation of the surge protection circuit described above, and the present disclosure will not repeat it here.

[0059] Based on the same concept, the present disclosure also provides an electronic device. Since the principle of solving problems of the electronic device embodiment is similar to that of the above-mentioned surge protection circuit embodiment, the implementation of the electronic device embodiment can be referred to the implementation of the above-mentioned surge protection circuit, and the repeated parts will not be repeated here.

[0060] Figure 3 A structural schematic diagram of an electronic device in an embodiment of the present disclosure is shown. The electronic device comprises a negative temperature coefficient (NTC) temperature measurement circuit 510, a processor 520, a power management integrated circuit (PMIC) 530, and a surge protection circuit 540.

[0061] The NTC temperature measurement circuit 510 is configured to detect the temperature of the power supply port of the electronic device.

[0062] The processor 520 is connected with the NTC temperature measurement circuit 510 and the PMIC 530 respectively, and is configured to send a control instruction to the PMIC 530 according to the temperature of the power supply port.

[0063] The PMIC 530 is connected with the control end of the switch unit in the surge protection circuit 540, and is configured to control the conduction and cutoff of the switch unit according to the control instruction.

[0064] Therefore, the scheme provided by the embodiment of the present disclosure can control the conduction and cutoff of the switch unit according to the temperature of the power supply port of the electronic device. Specifically, in the case of detecting that the temperature of the power supply port is too high, the processor 520 can issue a control instruction to the PMIC 530 to make the PMIC 530 output a high-level signal to the control end of the switch unit, and control the switch unit to conduct. At this time, the power supply connected to the electronic device will be directly grounded, that is, the power supply process to the electronic device is suspended, thereby avoiding the damage of the power supply port caused by the continuous power supply.

[0065] In some embodiments, a protection resistor (not shown in the figure) is further arranged between the PMIC 530 and the control end of the switch unit, so as to avoid damage to the switch unit caused by the voltage generated by static electricity during the assembly process of various circuits of the electronic device.

[0066] The embodiments of the present disclosure are described in detail above with reference to the drawings, but the present disclosure is not limited to the specific details in the above-described embodiments. Various simple modifications can be made to the technical solutions of the present disclosure within the technical concept of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0067] In addition, any combination of various different embodiments of the present disclosure can also be made, as long as it does not deviate from the idea of the present disclosure, and it should also be considered as disclosed by the present disclosure.

Claims

1. A surge protection circuit, characterized by, include: Switching unit and voltage suppression unit; The input terminal of the switching unit is connected to the power supply, and the output terminal of the switching unit is grounded. The first terminal of the voltage suppression unit is connected to the power supply, and the second terminal of the voltage suppression unit is connected to the control terminal of the switching unit. When the voltage output by the power supply is greater than the voltage turn-on threshold of the voltage suppression unit, the voltage suppression unit outputs a high-level signal to the control terminal of the switching unit to turn the switching unit on.

2. The surge protection circuit of claim 1, wherein, The voltage suppression unit includes: a diode and a first resistor; The cathode of the diode is connected to the power supply, and the anode of the diode is connected to the control terminal of the switching unit. The first end of the first resistor is connected to the anode of the diode, and the second end of the first resistor is grounded; The voltage turn-on threshold is the reverse breakdown voltage of the diode.

3. The surge protection circuit of claim 1, wherein, The surge protection circuit also includes: a DC protection unit; The DC protection unit is connected to the control terminals of the power supply and the switching unit, respectively. When the current output by the power supply passes through the DC protection unit, the DC protection unit outputs a high-level signal to the control terminal of the switching unit within a specified time period, so that the switching unit is in the conducting state.

4. The surge protection circuit of claim 3, wherein, The DC protection unit includes: a capacitor; The first end of the capacitor is connected to the power supply, and the second end of the capacitor is connected to the control terminal of the switching unit.

5. The surge protection circuit of claim 4, wherein, The DC protection unit further includes: a second resistor; The first end of the second resistor is connected to the second end of the capacitor, and the second end of the second resistor is grounded.

6. The surge protection circuit of claim 4 or 5, wherein, The capacitor is a polarized capacitor; The first end of the capacitor is the positive terminal of the polarized capacitor, and the second end of the capacitor is the negative terminal of the polarized capacitor.

7. The surge protection circuit of claim 1, wherein, The switching unit includes: a MOSFET; The drain of the MOS transistor is the input terminal of the switching unit, the source of the MOS transistor is the output terminal of the switching unit, and the gate of the MOS transistor is the control terminal of the switching unit.

8. A surge protection chip, characterized by, include: The surge protection circuit as described in any one of claims 1 to 7.

9. An electronic device, comprising: include: A negative temperature coefficient temperature measurement circuit, a processor, a power management integrated circuit, and a surge protection circuit as described in any one of claims 1 to 7; The negative temperature coefficient temperature measuring circuit is used to detect the temperature of the power supply port of the electronic device; The processor is connected to the negative temperature coefficient temperature measuring circuit and the power management integrated circuit respectively, and is used to send control commands to the power management integrated circuit according to the temperature of the power supply port. The power management integrated circuit is connected to the control terminal of the switching unit in the surge protection circuit, and is used to control the switching unit to turn on and off according to the control command.

10. The electronic device of claim 9, wherein, A protective resistor is also provided between the power management integrated circuit and the control terminal of the switching unit.

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