Hot plug protection circuit and intelligent door lock

Abstract

The utility model discloses a hot plug protection circuit and an intelligent door lock, the intelligent door lock comprises an indoor main board, an outdoor main board and a connecting wire harness, the connecting wire harness comprises a plug identification wire, and the hot plug protection circuit comprises a power supply input end used for being connected with a battery and a power supply output end used for being connected with the outdoor main board. The hot plug protection circuit comprises a switching circuit and a control circuit, the input end of the switching circuit is connected with the power input end, the output end of the switching circuit is connected with the power output end, the input end of the control circuit is used for being connected with a plug identification line, and the output end of the control circuit is connected with the controlled end of the switching circuit. According to the utility model, when the indoor main board and the outdoor main board are connected through the connecting wire harness, the outdoor main board is electrified so as to protect the safety of the indoor main board and the outdoor main board.

Description

Technical Field

[0001] The utility model relates to the technical field of hot plugging, in particular to a hot plugging protection circuit and an intelligent door lock. Background Art

[0002] Smart door locks generally include an indoor main board and an outdoor main board. The chip pins or power supply pins between the indoor main board and the outdoor main board are generally connected through a wiring harness. However, hot plugging often occurs during the installation of existing smart door locks. Hot plugging means plugging with power on. Hot plugging means that the user inserts or unplugs the wiring harness connecting the indoor main board and the outdoor main board without shutting down the system or cutting off the power supply. This operation can easily cause the internal chip of the smart door lock to be subjected to irreversible electrical damage due to static electricity or power-on surge. Utility Model Content

[0003] The main purpose of the utility model is to provide a hot-swap protection circuit and an intelligent door lock, which aims to realize power supply to the outdoor mainboard after the indoor mainboard and the outdoor mainboard are connected by a wiring harness, so as to protect the safety of the indoor mainboard and the outdoor mainboard.

[0004] To achieve the above-mentioned purpose, the hot-swap protection circuit proposed in the utility model is applied to a smart door lock, wherein the smart door lock comprises an indoor mainboard, an outdoor mainboard and a connecting harness, wherein the connecting harness is used to connect the indoor mainboard and the outdoor mainboard, wherein the connecting harness comprises a plug-in identification line, wherein the indoor mainboard comprises the hot-swap protection circuit and a battery, wherein the hot-swap protection circuit comprises a power input terminal for accessing the battery and a power output terminal for accessing the outdoor mainboard, wherein the hot-swap protection circuit comprises:

[0005] A switch circuit, wherein an input end of the switch circuit is connected to the power input end, and an output end of the switch circuit is connected to the power output end;

[0006] A control circuit, wherein the input end of the control circuit is used to be connected to the plug-in identification line, and the output end of the control circuit is connected to the controlled end of the switch circuit; when the input end of the control circuit is connected to the outdoor mainboard through the plug-in identification line, the output end of the control circuit outputs a connection signal to control the switch circuit to be turned on; when the input end of the control circuit is not connected to the outdoor mainboard through the plug-in identification line, the output end of the control circuit outputs a disconnection signal to control the switch circuit to be disconnected.

[0007] Optionally, the plug-in identification line includes:

[0008] A first resistor, one end of the first resistor is grounded, when the other end of the first resistor is connected to the input end of the control circuit, the output end of the control circuit outputs the connection signal to control the switch circuit to be turned on; when the other end of the first resistor is not connected to the input end of the control circuit, the output end of the control circuit outputs the disconnection signal to control the switch circuit to be turned off.

[0009] Optionally, the control circuit includes:

[0010] a first switch tube, a second switch tube, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein the first end of the second resistor is connected to the power input end, the second end of the second resistor is connected to the controlled end of the first switch tube, the controlled end of the first switch tube is also used to be connected to the other end of the first resistor, and the output end of the first switch tube is grounded; the controlled end of the second switch tube is connected to the input end of the first switch tube, the input end of the second switch tube and the first end of the third resistor are both connected to the power input end, the second end of the third resistor is connected to the controlled end of the second switch tube, the output end of the second switch tube is respectively connected to the controlled end of the switch circuit and the first end of the fourth resistor, the second end of the fourth resistor is grounded, the first end of the fifth resistor is connected to the power input end, and the second end of the fifth resistor is connected to the first end of the fourth resistor;

[0011] Wherein, the controlled end of the first switch tube is the input end of the control circuit, and the output end of the second switch tube is the output end of the control circuit.

[0012] Optionally, the switch circuit includes:

[0013] A third switch tube, wherein the input end of the third switch tube is connected to the power input end, the output end of the third switch tube is connected to the power output end, and the controlled end of the third switch tube is connected to the output end of the second switch tube; wherein the controlled end of the third switch tube is the controlled end of the switch circuit.

[0014] Optionally, the control circuit includes:

[0015] A main control chip, wherein the input end of the main control chip is used to be connected to the other end of the first resistor, and the output end of the main control chip is connected to the controlled end of the switch circuit; when the other end of the first resistor is connected to the input end of the main control chip, the output end of the main control chip outputs the connection signal to control the switch circuit to be turned on; when the other end of the first resistor is not connected to the input end of the main control chip, the output end of the main control chip outputs the disconnection signal to control the switch circuit to be disconnected.

[0016] Optionally, the control circuit further includes:

[0017] A voltage divider circuit, wherein the first end of the voltage divider circuit is used to be connected to the other end of the first resistor, the input end of the main control chip includes an ADC sampling end, the second end of the voltage divider circuit is electrically connected to the ADC sampling end, the main control chip collects the voltage of the voltage divider circuit according to the ADC sampling end, and outputs the connection signal / the disconnection signal to control the switching circuit to be turned on / off; the power supply end of the voltage divider circuit is connected to the power input end, and the ground end of the voltage divider circuit is grounded.

[0018] Optionally, the voltage divider circuit includes:

[0019] A sixth resistor and a seventh resistor, wherein the first end of the sixth resistor is connected to the power input terminal, the second end of the sixth resistor is connected to the first end of the seventh resistor, the second end of the seventh resistor is grounded, the second end of the sixth resistor and the first end of the seventh resistor are used to be connected to the other end of the first resistor, and the second end of the sixth resistor and the first end of the seventh resistor are also connected to the ADC sampling terminal.

[0020] Optionally, the switch circuit includes:

[0021] A fourth switch tube, a fifth switch tube, an eighth resistor and a ninth resistor, wherein the controlled end of the fourth switch tube is connected to the output end of the main control chip, the input end of the fourth switch tube is connected to the second end of the ninth resistor, and the output end of the fourth switch tube is grounded; the first end of the eighth resistor is connected to the controlled end of the fourth switch tube, and the second end of the eighth resistor is grounded; the first end of the ninth resistor is connected to the power input end; the input end of the fifth switch tube is connected to the power input end, the output end of the fifth switch tube is connected to the power output end, and the controlled end of the fifth switch tube is connected to the input end of the fourth switch tube.

[0022] Optionally, the hot-swap protection circuit further includes:

[0023] A slow start circuit, wherein a first end of the slow start circuit is connected to an input end of the switch circuit, a second end of the slow start circuit is connected to a controlled end of the switch circuit, and the slow start circuit is used to slow down a conduction process of the switch circuit.

[0024] A smart door lock comprises an indoor main board, an outdoor main board, a connecting wire harness and a hot-swap protection circuit as described in any one of the above items.

[0025] The utility model hot-swap protection circuit comprises a switch circuit and a control circuit. When the input end of the control circuit is connected to the outdoor mainboard through the plug-in identification line, that is, the indoor mainboard is connected to the outdoor mainboard through the connecting wire harness, the output end of the control circuit outputs a connection signal to control the switch circuit to be turned on, thereby turning on the path between the power input end and the power output end, so that the battery of the indoor mainboard supplies power to the outdoor mainboard; when the input end of the control circuit is not connected to the outdoor mainboard through the plug-in identification line, that is, the indoor mainboard is not connected to the outdoor mainboard through the connecting wire harness, the output end of the control circuit outputs a disconnection signal to control the switch circuit to disconnect the path between the power input end and the power output end, so that the battery of the indoor mainboard stops supplying power to the outdoor mainboard. With such a setting, in actual application, when the user installs the indoor mainboard and the outdoor mainboard, if the indoor mainboard and the outdoor mainboard are not connected through the connecting wire harness, the battery in the indoor mainboard cannot be powered on to the outdoor mainboard, and the user will not experience hot-swap phenomenon when plugging and unplugging the wire harness at this time; until the indoor mainboard and the outdoor mainboard are connected through the connecting wire harness, the path between the power input end and the power output end is turned on, and the battery in the indoor mainboard supplies power to the outdoor mainboard. For users, they do not need to worry about inserting or unplugging the wiring harness when installing the smart door lock, or incorrectly inserting or unplugging the wiring harness may cause damage to the indoor or outdoor main board, thereby improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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 only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0027] Figure 1 This is a schematic diagram of a module of an embodiment of the utility model;

[0028] Figure 2 This is a schematic diagram of a module of another embodiment of the utility model;

[0029] Figure 3 This is a schematic diagram of the circuit structure of another embodiment of the utility model;

[0030] Figure 4 This is a module schematic diagram of another embodiment of the utility model;

[0031] Figure 5 This is a module schematic diagram of yet another embodiment of the utility model;

[0032] Figure 6 This is a schematic diagram of the circuit structure of another embodiment of the utility model;

[0033] Figure 7 This is a schematic diagram of the circuit structure of another embodiment of the utility model;

[0034] Figure 8 This is a module schematic diagram of yet another embodiment of the present utility model.

[0035] Description of Figure Numbers:

[0036] Label name Label name 10 Plug and unplug identification line 32 Voltage divider circuit 20 Switching Circuit 40 Slow start circuit 30 Control Circuit 31 Main control chip

[0037] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments 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.

[0039] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0040] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0041] Smart door locks generally include an indoor main board and an outdoor main board. The chip pins or power supply pins between the indoor main board and the outdoor main board are generally connected through a wiring harness. However, hot plugging often occurs during the installation of existing smart door locks. Hot plugging means plugging with power on. Hot plugging means that the user inserts or unplugs the wiring harness connecting the indoor main board and the outdoor main board without shutting down the system or cutting off the power supply. This operation can easily cause the internal chip of the smart door lock to be subjected to irreversible electrical damage due to static electricity or power-on surge.

[0042] To this end, the utility model proposes a hot-swap protection circuit, which is applied to a smart door lock. The smart door lock includes an indoor mainboard, an outdoor mainboard and a connecting harness, the connecting harness is used to connect the indoor mainboard and the outdoor mainboard, the connecting harness includes a plug identification line 10, the indoor mainboard includes the hot-swap protection circuit and a battery, the hot-swap protection circuit includes a power input terminal for accessing the battery and a power output terminal for accessing the outdoor mainboard, reference Figure 1 , the hot-swap protection circuit includes:

[0043] A switch circuit 20, wherein an input end of the switch circuit 20 is connected to the power input end, and an output end of the switch circuit 20 is connected to the power output end;

[0044] A control circuit 30, wherein the input end of the control circuit 30 is used to be connected to the plug-in identification line 10, and the output end of the control circuit 30 is connected to the controlled end of the switch circuit 20; when the input end of the control circuit 30 is connected to the outdoor main board through the plug-in identification line 10, the output end of the control circuit 30 outputs a connection signal to control the switch circuit 20 to be turned on; when the input end of the control circuit 30 is not connected to the outdoor main board through the plug-in identification line 10, the output end of the control circuit 30 outputs a disconnection signal to control the switch circuit 20 to be disconnected.

[0045] In this embodiment, optionally, the switching circuit 20 can be implemented by using at least one switching tube, such as a MOS tube, an IGBT tube, a thyristor, a triode, a power tube, etc., and / or by using at least one switching device, such as a contactor, a circuit breaker and a relay.

[0046] In this embodiment, optionally, the control circuit 30 can be implemented by a main controller, such as an MCU (Microcontroller Unit), a DSP (Digital Signal Process), an FPGA (Field Programmable Gate Array), a SOC (System OnChip), etc.; the control circuit 30 can also be implemented by a circuit consisting of a number of switching tubes and a load.

[0047] In this embodiment, the connecting harness includes a power line and a signal line. The indoor main board is connected to the outdoor main board through the connecting harness including the power line and the signal line to realize power supply and communication for the outdoor main board. The plug-in identification line 10 can be a signal line, or it can be one or more identification lines specially set in the connecting harness for identifying the connection status between the outdoor main board and the indoor main board in addition to the power line and the signal line. The connecting harness is connected together through a harness connector to realize unified plug-in and pull-out. That is, when one of the lines in the connecting harness is connected to the indoor main board / outdoor main board, the other lines of the connecting harness are also synchronously connected to the indoor main board / outdoor main board.

[0048] Specifically, when the input end of the control circuit 30 is connected to the outdoor mainboard through the plug-in identification line 10, that is, the indoor mainboard is connected to the outdoor mainboard through the connecting harness, the output end of the control circuit 30 outputs a connection signal to control the switch circuit 20 to conduct, thereby conducting the path between the power input end and the power output end, so that the battery of the indoor mainboard supplies power to the outdoor mainboard; when the input end of the control circuit 30 is not connected to the outdoor mainboard through the plug-in identification line 10, that is, the indoor mainboard is not connected to the outdoor mainboard through the connecting harness, the output end of the control circuit 30 outputs a disconnection signal to control the switch circuit 20 to disconnect the path between the power input end and the power output end, so that the battery of the indoor mainboard stops supplying power to the outdoor mainboard. With such a setting, in actual application, when the user installs the indoor mainboard and the outdoor mainboard, if the indoor mainboard and the outdoor mainboard are not connected through the connecting harness, the battery in the indoor mainboard cannot be powered on to the outdoor mainboard, and the user will not experience hot plugging when plugging and unplugging the harness; until the indoor mainboard and the outdoor mainboard are connected through the connecting harness, the path between the power input end and the power output end is conducted, and the battery in the indoor mainboard supplies power to the outdoor mainboard. For users, they do not need to worry about inserting or unplugging the connecting harness when installing the smart door lock, or incorrectly inserting or unplugging the connecting harness may cause damage to the indoor or outdoor main board, thereby improving the user experience.

[0049] refer to Figure 2 In one embodiment of the present utility model, the plug-in identification line 10 comprises:

[0050] A first resistor R1, one end of the first resistor R1 is grounded, when the other end of the first resistor R1 is connected to the input end of the control circuit 30, the output end of the control circuit 30 outputs the connection signal to control the switch circuit 20 to be turned on; when the other end of the first resistor R1 is not connected to the input end of the control circuit 30, the output end of the control circuit 30 outputs the disconnection signal to control the switch circuit 20 to be disconnected.

[0051] In this embodiment, when the indoor main board is connected to the outdoor main board through a connecting harness, the other end of the first resistor R1 is connected to the input end of the control circuit 30, the voltage at the input end of the control circuit 30 is pulled down, and the control circuit 30 detects that the input voltage is reduced and then outputs a connection signal to control the switch circuit 20 to turn on; when the indoor main board is not connected to the outdoor main board through a connecting harness, the other end of the first resistor R1 is not connected to the input end of the control circuit 30, the voltage of the control circuit 30 is not pulled down, the control circuit 30 detects that the input voltage has not changed, and the output end of the control circuit 30 outputs a disconnect signal to control the switch circuit 20 to disconnect.

[0052] It should be noted that the first resistor R1 can be set on the outdoor main board. When the plug-in identification line 10 is connected to the outdoor main board, one end of the plug-in identification line 10 is connected to the other end of the first resistor R1, that is, the other end of the first resistor R1 is used to connect to the input end of the control circuit 30 through the plug-in identification line 10.

[0053] refer to Figure 3 In one embodiment of the utility model, the control circuit 30 includes: a first switch tube Q1, a second switch tube Q2, a second resistor R2, a third resistor R3, a fourth resistor R4 and a fifth resistor R5, wherein a first end of the second resistor R2 is connected to the power input end, a second end of the second resistor R2 is connected to the controlled end of the first switch tube Q1, the controlled end of the first switch tube Q1 is also used to be connected to the other end of the first resistor R1, and an output end of the first switch tube Q1 is grounded; a controlled end of the second switch tube Q2 is connected to the input end of the first switch tube Q1, the input end of the second switch tube Q2 and the first end of the third resistor R3 are both connected to the power input end, a second end of the third resistor R3 is connected to the controlled end of the second switch tube Q2, an output end of the second switch tube Q2 is respectively connected to the controlled end of the switch circuit 20 and the first end of the fourth resistor R4, a second end of the fourth resistor R4 is grounded, a first end of the fifth resistor R5 is connected to the power input end, and a second end of the fifth resistor R5 is connected to the first end of the fourth resistor R4.

[0054] The controlled end of the first switch tube Q1 is the input end of the control circuit 30 , and the output end of the second switch tube Q2 is the output end of the control circuit 30 .

[0055] In this embodiment, the switch circuit 20 includes: a third switch tube Q3, the input end of the third switch tube Q3 is connected to the power input end, the output end of the third switch tube Q3 is connected to the power output end, and the controlled end of the third switch tube Q3 is connected to the output end of the second switch tube Q2; wherein the controlled end of the third switch tube Q3 is the controlled end of the switch circuit 20.

[0056] In this embodiment, optionally, the first switch tube Q1, the second switch tube Q2 and the third switch tube Q3 can be implemented by at least one of a MOS tube, an IGBT tube, a thyristor, a triode, a power tube and the like.

[0057] In this embodiment, the first switch tube Q1 is an NMOS tube, the second switch tube Q2 is a PMOS tube, and the third switch tube Q3 is a PMOS tube. When the controlled end of the first switch tube Q1 is not connected to the outdoor main board through the plug-in identification line 10, that is, the indoor main board is not connected to the outdoor main board through the plug-in identification line 10, the other end of the first resistor R1 is not connected to the controlled end of the first switch tube Q1. At this time, the voltage of the controlled end of the first switch tube Q1 is the voltage of the power input end, that is, the high level. The first switch tube Q1 is turned on, and the voltage of the controlled end of the second switch tube Q2 is pulled down by the turned-on first switch tube Q1, and the second switch tube Q2 is turned on. At this time, the voltage of the fourth resistor R4 is the voltage of the power input end, and the voltage of the controlled end of the third switch tube Q3 is the voltage of the fourth resistor R4. , the third switch tube Q3 is disconnected; when the controlled end of the first switch tube Q1 is connected to the outdoor main board through the plug-in identification line 10, that is, the indoor main board is connected to the outdoor main board through the connecting harness, the other end of the first resistor R1 is connected to the controlled end of the first switch tube Q1, and at this time, the voltage of the controlled end of the first switch tube Q1 is pulled down to a low level, and the first switch tube Q1 is disconnected. Since the voltage of the controlled end of the second switch tube Q2 is pulled up to the voltage of the power input end at this time, the second switch tube Q2 is disconnected, and because the current flowing through the fourth resistor R4 at this time also needs to flow through the fifth resistor R5, the voltage of the fourth resistor R4 is relatively small at this time, that is, the voltage of the controlled end of the third switch tube Q3 is a low level, and the third switch tube Q3 is turned on, thereby turning on the path between the power input end and the power output end.

[0058] It should be noted that the resistance of the first resistor R1 in this embodiment is small enough so that after the first resistor R1 is connected to the controlled end of the first switch tube Q1, the voltage obtained by the first resistor R1 dividing the power input end is lower than the turn-on voltage of the first switch tube Q1.

[0059] refer to Figure 4 In one embodiment of the present utility model, the control circuit 30 includes:

[0060] A main control chip 31, wherein the input end of the main control chip 31 is used to be connected to the other end of the first resistor R1, and the output end of the main control chip 31 is connected to the controlled end of the switch circuit 20; when the other end of the first resistor R1 is connected to the input end of the main control chip 31, the output end of the main control chip 31 outputs the connection signal to control the switch circuit 20 to be turned on; when the other end of the first resistor R1 is not connected to the input end of the main control chip 31, the output end of the main control chip 31 outputs the disconnection signal to control the switch circuit 20 to be turned off.

[0061] In this embodiment, optionally, the main control chip 31 can be implemented by a main controller, such as MCU (Microcontroller Unit), DSP (Digital Signal Process), FPGA (Field Programmable Gate Array), SOC (System OnChip), etc.

[0062] In this embodiment, when the input end of the main control chip 31 is connected to the outdoor main board through the plug-in identification line 10, that is, the indoor main board is connected to the outdoor main board through the connecting wiring harness, the other end of the first resistor R1 is connected to the input end of the main control chip 31, and the voltage at the input end of the main control chip 31 is pulled down. After the main control chip 31 detects that the voltage at the input end is pulled down, the output end of the main control chip 31 outputs a connection signal to control the switch circuit 20 to turn on; when the input end of the main control chip 31 is not connected to the outdoor main board through the plug-in identification line 10, that is, the indoor main board is not connected to the outdoor main board through the connecting wiring harness, and the other end of the first resistor R1 is not connected to the input end of the main control chip 31, the voltage at the input end of the main control chip 31 does not change. At this time, the output end of the main control chip 31 outputs a disconnect signal to control the switch circuit 20 to disconnect.

[0063] refer to Figure 5 In one embodiment of the present utility model, the main control circuit further includes:

[0064] A voltage divider circuit 32, wherein the first end of the voltage divider circuit 32 is used to be connected to the other end of the first resistor R1, the input end of the main control chip 31 includes an ADC sampling end, the second end of the voltage divider circuit 32 is electrically connected to the ADC sampling end, the main control chip 31 collects the voltage of the voltage divider circuit 32 according to the ADC sampling end, and outputs the connection signal / the disconnection signal to control the switching circuit 20 to be turned on / off; the power supply end of the voltage divider circuit 32 is connected to the power input end, and the ground end of the voltage divider circuit 32 is grounded.

[0065] In this embodiment, the voltage divider circuit 32 is used to divide the voltage of the power input end. The main control chip 31 outputs a connection signal / disconnection signal to control the switch circuit 20 to be turned on / off according to the voltage of the voltage divider circuit 32 sampled by the ADC sampling end. When the other end of the first resistor R1 is connected to the first end of the voltage divider circuit 32, since one end of the first resistor R1 is grounded, when the voltage of the voltage divider circuit 32 becomes low, the main control chip 31 detects that the voltage of the voltage divider circuit 32 becomes low through the ADC sampling end. At this time, the output end of the main control chip 31 outputs a connection signal to control the switch circuit 20 to be turned on, thereby turning on the path between the power input end and the power output end; when the other end of the first resistor R1 is not connected to the first end of the voltage divider circuit 32, the voltage of the voltage divider circuit 32 remains unchanged, and the main control chip 31 outputs a disconnection signal to control the switch circuit 20 to be disconnected, thereby disconnecting the path between the power input end and the power output end. For example, when the user does not connect the indoor main board and the outdoor main board through the connecting harness, the other end of the first resistor R1 is not connected to the first end of the voltage divider circuit 32, and the voltage of the voltage divider circuit 32 remains unchanged. After the main control chip 31 samples the voltage of the voltage divider circuit 32 through the ADC sampling end and finds that the voltage remains unchanged, the output disconnect signal controls the switch circuit 20 to disconnect, thereby disconnecting the path between the power input end and the power output end, thereby avoiding hot plugging during the user's installation of the indoor main board and the outdoor main board.

[0066] refer to Figure 6 In this embodiment, the voltage divider circuit 32 includes: a sixth resistor R6 and a seventh resistor R7, a first end of the sixth resistor R6 is connected to the power input end, a second end of the sixth resistor R6 is connected to the first end of the seventh resistor R7, a second end of the seventh resistor R7 is grounded, a second end of the sixth resistor R6 and a first end of the seventh resistor R7 are used to be connected to the other end of the first resistor R1, and a second end of the sixth resistor R6 and a first end of the seventh resistor R7 are also connected to the ADC sampling end.

[0067] In this embodiment, when the other end of the first resistor R1 is connected to the second end of the sixth resistor R6 and the first end of the seventh resistor R7, since one end of the first resistor R1 is grounded, the equivalent resistance of the first resistor R1 and the seventh resistor R7 in parallel becomes smaller than the resistance of the seventh resistor R7, and the voltage obtained thereby also becomes smaller. At this time, the voltage sampled by the ADC sampling end of the main control chip 31 becomes smaller, and the output end of the main control chip 31 outputs a connection signal to turn on the switch circuit 20, thereby turning on the path between the power input end and the power output end; when the other end of the first resistor R1 is not connected to the second end of the sixth resistor R6 and the first end of the seventh resistor R7, the voltage sampled by the ADC sampling end of the main control chip 31 remains unchanged, and at this time, the output end of the main control chip 31 outputs a disconnection signal to control the switch circuit 20 to disconnect, thereby disconnecting the path between the power input end and the power output end.

[0068] refer to Figure 7 In this embodiment, the switch circuit 20 includes: a fourth switch tube Q4, a fifth switch tube Q5, an eighth resistor R8 and a ninth resistor R9, the controlled end of the fourth switch tube Q4 is connected to the output end of the main control chip 31, the input end of the fourth switch tube Q4 is connected to the second end of the ninth resistor R9, and the output end of the fourth switch tube Q4 is grounded; the first end of the eighth resistor R8 is connected to the controlled end of the fourth switch tube Q4, and the second end of the eighth resistor R8 is grounded; the first end of the ninth resistor R9 is connected to the power input end; the input end of the fifth switch tube Q5 is connected to the power input end, the output end of the fifth switch tube Q5 is connected to the power output end, and the controlled end of the fifth switch tube Q5 is connected to the input end of the fourth switch tube Q4.

[0069] In this embodiment, optionally, in this embodiment, the fourth switch tube Q4 and the fifth switch tube Q5 can be implemented by at least one of a MOS tube, an IGBT tube, a thyristor, a triode, a power tube, etc.

[0070] In this embodiment, the disconnect signal is a low level signal, and the connect signal is a high level signal.

[0071] In this embodiment, the fourth switch tube Q4 and the fifth switch tube Q5 are NMOS tubes and PMOS tubes respectively. When the output end of the main control chip 31 outputs a disconnection signal to the controlled end of the fourth switch tube Q4, the fourth switch tube Q4 is disconnected. Since the controlled end of the fifth switch tube Q5 is respectively connected to the second end of the ninth resistor R9, and the first end of the ninth resistor R9 is connected to the power input end, the voltage of the controlled end of the fifth switch tube Q5 is the voltage of the power input end at this time. The fifth switch tube Q5 is disconnected, and the path between the power input end and the power output end is disconnected; when the main control chip 31 outputs a connection signal to the controlled end of the fourth switch tube Q4, the fourth switch tube Q4 is turned on. Since the output end of the fourth switch tube Q4 is grounded, the voltage of the controlled end of the fifth switch tube Q5 is pulled down at this time, and the fifth switch tube Q5 is turned on, so that the path between the power input end and the power output end is turned on.

[0072] refer to Figure 8 In one embodiment of the present utility model, the hot-swap protection circuit further includes:

[0073] A slow start circuit 40 , wherein a first end of the slow start circuit 40 is connected to an input end of the switch circuit 20 , and a second end of the slow start circuit 40 is connected to a controlled end of the switch circuit 20 , and the slow start circuit 40 is used to slow down a conduction process of the switch circuit 20 .

[0074] In this embodiment, the slow start circuit 40 includes a capacitor, a first end of the capacitor C1 is connected to the input end of the switch circuit 20, and a second end of the capacitor C1 is connected to the controlled end of the switch circuit 20. The capacitor C1 can slow down the voltage change of the controlled end of the switch circuit 20, thereby slowing down the conduction process of the switch circuit 20, thereby preventing the current at the power input end from directly flowing into the power output end when the switch circuit 20 is directly turned on and causing a current impact on the subsequent circuit of the power output end. For example, when the switch circuit 20 is high-level disconnected and low-level turned on, the connection signal is low-level and the disconnection signal is high-level; if the switch circuit 20 changes from the disconnected state to the turned-on state, the voltage of the controlled end of the switch circuit 20 will drop. Due to the discharge characteristics of the capacitor C1, the current discharged by the capacitor C1 will flow to the controlled end of the switch circuit 20, so that the voltage of the controlled end of the switch circuit 20 slows down, thereby slowing down the conduction process of the switch circuit 20. For another example, when the switch circuit 20 is turned on at a high level and turned off at a low level, the connection signal is at a high level and the disconnection signal is at a low level; if the switch circuit 20 changes from the disconnected state to the on state, the voltage at the controlled end of the switch circuit 20 will rise. Due to the charging characteristics of the capacitor C1, part of the current of the connection signal will first charge the capacitor C1. At this time, the switch circuit 20 is not fully turned on. Until the capacitor C1 is fully charged, the connection signal is fully output to the controlled end of the switch circuit 20. At this time, the switch circuit 20 will be fully turned on, thereby slowing down the conduction process of the switch circuit 20.

[0075] The utility model also proposes a smart door lock, comprising an indoor main board, an outdoor main board, a connecting wiring harness and the hot-swap protection circuit described in any one of the above items, wherein the connecting wiring harness comprises a plug-in identification line, the connecting wiring harness is used to connect the indoor main board and the outdoor main board, the indoor main board comprises the hot-swap protection circuit and a battery, and the hot-swap protection circuit comprises a power input terminal for connecting to the battery and a power output terminal for connecting to the outdoor main board.

[0076] It is worth noting that since the smart door lock of the present invention is based on the above-mentioned hot-swap protection circuit, the embodiments of the smart door lock of the present invention include all technical solutions of all embodiments of the above-mentioned hot-swap protection circuit, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0077] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A hot-swap protection circuit, applied to a smart door lock, the smart door lock comprises an indoor mainboard, an outdoor mainboard and a connecting harness, the connecting harness is used to connect the indoor mainboard and the outdoor mainboard, the connecting harness comprises a plug identification line, the indoor mainboard comprises the hot-swap protection circuit and a battery, the hot-swap protection circuit comprises a power input terminal for accessing the battery and a power output terminal for accessing the outdoor mainboard, characterized in that: The hot-swap protection circuit comprises: A switch circuit, wherein an input end of the switch circuit is connected to the power input end, and an output end of the switch circuit is connected to the power output end; A control circuit, wherein the input end of the control circuit is used to be connected to the plug-in identification line, and the output end of the control circuit is connected to the controlled end of the switch circuit; when the input end of the control circuit is connected to the outdoor mainboard through the plug-in identification line, the output end of the control circuit outputs a connection signal to control the switch circuit to be turned on; when the input end of the control circuit is not connected to the outdoor mainboard through the plug-in identification line, the output end of the control circuit outputs a disconnection signal to control the switch circuit to be disconnected.

2. The hot-swap protection circuit according to claim 1, characterized in that: The plug-in identification line comprises: A first resistor, one end of the first resistor is grounded, when the other end of the first resistor is connected to the input end of the control circuit, the output end of the control circuit outputs the connection signal to control the switch circuit to be turned on; when the other end of the first resistor is not connected to the input end of the control circuit, the output end of the control circuit outputs the disconnection signal to control the switch circuit to be turned off.

3. The hot-swap protection circuit according to claim 2, characterized in that: The control circuit comprises: a first switch tube, a second switch tube, a second resistor, a third resistor, a fourth resistor and a fifth resistor, wherein the first end of the second resistor is connected to the power input end, the second end of the second resistor is connected to the controlled end of the first switch tube, the controlled end of the first switch tube is also used to be connected to the other end of the first resistor, and the output end of the first switch tube is grounded; the controlled end of the second switch tube is connected to the input end of the first switch tube, the input end of the second switch tube and the first end of the third resistor are both connected to the power input end, the second end of the third resistor is connected to the controlled end of the second switch tube, the output end of the second switch tube is respectively connected to the controlled end of the switch circuit and the first end of the fourth resistor, the second end of the fourth resistor is grounded, the first end of the fifth resistor is connected to the power input end, and the second end of the fifth resistor is connected to the first end of the fourth resistor; Wherein, the controlled end of the first switch tube is the input end of the control circuit, and the output end of the second switch tube is the output end of the control circuit.

4. The hot-swap protection circuit according to claim 3, characterized in that: The switch circuit comprises: A third switch tube, wherein the input end of the third switch tube is connected to the power input end, the output end of the third switch tube is connected to the power output end, and the controlled end of the third switch tube is connected to the output end of the second switch tube; wherein the controlled end of the third switch tube is the controlled end of the switch circuit.

5. The hot-swap protection circuit according to claim 2, characterized in that: The control circuit comprises: A main control chip, wherein the input end of the main control chip is used to be connected to the other end of the first resistor, and the output end of the main control chip is connected to the controlled end of the switch circuit; when the other end of the first resistor is connected to the input end of the main control chip, the output end of the main control chip outputs the connection signal to control the switch circuit to be turned on; when the other end of the first resistor is not connected to the input end of the main control chip, the output end of the main control chip outputs the disconnection signal to control the switch circuit to be disconnected.

6. The hot-swap protection circuit according to claim 5, characterized in that: The control circuit further comprises: A voltage divider circuit, wherein the first end of the voltage divider circuit is used to be connected to the other end of the first resistor, the input end of the main control chip includes an ADC sampling end, the second end of the voltage divider circuit is electrically connected to the ADC sampling end, the main control chip collects the voltage of the voltage divider circuit according to the ADC sampling end, and outputs the connection signal / the disconnection signal to control the switching circuit to be turned on / off; the power supply end of the voltage divider circuit is connected to the power input end, and the ground end of the voltage divider circuit is grounded.

7. The hot-swap protection circuit according to claim 6, characterized in that: The voltage divider circuit comprises: A sixth resistor and a seventh resistor, wherein the first end of the sixth resistor is connected to the power input terminal, the second end of the sixth resistor is connected to the first end of the seventh resistor, the second end of the seventh resistor is grounded, the second end of the sixth resistor and the first end of the seventh resistor are used to be connected to the other end of the first resistor, and the second end of the sixth resistor and the first end of the seventh resistor are also connected to the ADC sampling terminal.

8. The hot-swap protection circuit according to claim 7, characterized in that: The switch circuit comprises: A fourth switch tube, a fifth switch tube, an eighth resistor and a ninth resistor, wherein the controlled end of the fourth switch tube is connected to the output end of the main control chip, the input end of the fourth switch tube is connected to the second end of the ninth resistor, and the output end of the fourth switch tube is grounded; the first end of the eighth resistor is connected to the controlled end of the fourth switch tube, and the second end of the eighth resistor is grounded; the first end of the ninth resistor is connected to the power input end; the input end of the fifth switch tube is connected to the power input end, the output end of the fifth switch tube is connected to the power output end, and the controlled end of the fifth switch tube is connected to the input end of the fourth switch tube.

9. The hot-swap protection circuit according to claim 1, characterized in that: The hot-swap protection circuit also includes: A slow start circuit, wherein a first end of the slow start circuit is connected to an input end of the switch circuit, a second end of the slow start circuit is connected to a controlled end of the switch circuit, and the slow start circuit is used to slow down a conduction process of the switch circuit.

10. A smart door lock, characterized in that: The invention comprises an indoor main board, an outdoor main board, a connecting wire harness and a hot-swap protection circuit as claimed in any one of claims 1 to 9.

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