Protection circuit and game equipment

Abstract

The invention provides a protection circuit and game equipment. The protection circuit is connected between the quick connection interface and the MCU, and the quick connection interface comprises a power supply end, a first signal end and a second signal end; the protection circuit comprises a detection circuit, a first switch tube and a second switch tube. The input end of the detection circuit is connected with the power end of the quick connection interface and can respond to the access condition of the power end voltage and output a first level control signal or a second level control signal. The first switch tube is connected to the first signal end and the MCU, the second switch tube is connected to the second signal end and the MCU, and the first switch tube and the second switch tube are both connected with the output end of the detection circuit. When a power supply signal is connected to the power supply end of the quick connection interface, the detection circuit outputs a first level control signal, and the first switch tube and the second switch tube are conducted, so that the signal end is communicated with the MCU; and when the power supply signal is not accessed, a second level control signal is output, the first switch tube and the second switch tube are disconnected, and the connection between the signal end and the MCU is cut off, so that the working safety of the MCU is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of circuit, in particular to a protection circuit and a game device comprising the same. BACKGROUND

[0002] In the field of automobile, industrial control, etc., the base and the steering wheel are often detachably connected through a quick release structure. After the physical connection is completed through the quick release structure, the base needs to provide 12V power supply for the steering wheel and realize data communication through signal contacts. However, the existing quick release structure has defects. The locking needs the base and the steering wheel to be relatively rotated to a specific position, and during the rotation process, the power contacts and the signal contacts in the quick release structure are easy to be miscontacted due to position deviation. Once the 12V power is miscontacted to the signal line, the high voltage will intrude into the MCU signal pin in the steering wheel, far exceeding the tolerance range of the MCU, causing the MCU to fail, and further causing equipment failure, increasing maintenance cost and safety hazards. SUMMARY

[0003] The present application aims to provide a protection circuit and a game device to solve the problems mentioned in the background.

[0004] To solve the above problems, in a first aspect, a protection circuit is provided, which is used to be connected between a quick connection interface and an MCU. The quick connection interface includes a power supply end and a signal end, and the signal end includes a first signal end and a second signal end. The protection circuit includes a detection circuit, which includes an input end and an output end. The input end is used to be connected with the power supply end of the quick connection interface. The detection circuit is used to output corresponding control signals through the output end in response to the voltage access state of the power supply end of the quick connection interface. The control signals include a first level control signal and a second level control signal. A first switch tube is used to be connected between the first signal end and the MCU. A second switch tube is used to be connected between the second signal end and the MCU. The first switch tube and the second switch tube are also connected with the output end of the detection circuit. When the power supply signal is accessed to the power supply end of the quick connection interface, the detection circuit outputs the first level control signal through the output end. The first switch tube and the second switch tube are turned on in response to the first level control signal, thereby turning on the connection between the first signal end, the second signal end and the MCU. When the power supply signal is not accessed to the power supply end of the quick connection interface, the detection circuit outputs the second level control signal through the output end. The first switch tube and the second switch tube are turned off in response to the second level control signal, thereby turning off the connection between the first signal end, the second signal end and the MCU.

[0005] In one of the embodiments, the first switch tube comprises a first connection end, a second connection end and a first control end, the second switch tube comprises a third connection end, a fourth connection end and a second control end, the first connection end of the first switch tube is connected with the first signal end of the quick connection interface, the second connection end of the first switch tube is connected with the first signal pin of the MCU, the third connection end of the second switch tube is connected with the second signal end of the quick connection interface, the fourth end of the second switch tube is connected with the second signal pin of the MCU, and the first control end of the first switch tube and the second control end of the second switch tube are both connected with the output end of the detection circuit.

[0006] In one of the embodiments, the first switch tube and the second switch tube are high-level conduction switch tubes, the first level control signal is a high-level signal, the second level control signal is a low-level signal, the detection circuit comprises a first resistor and a second resistor, the first resistor and the second resistor are connected in series between the input end and the ground end, a first connection node of the first resistor and the second resistor is connected with the output end of the detection circuit, wherein, when the power signal is connected to the power end of the quick connection interface, the first connection node is at a high level, so that the output end outputs the first level control signal which is a high-level signal, and the first switch tube and the second switch tube are controlled to be turned on; when the power signal is not connected to the power end of the quick connection interface, the first connection node is grounded through the second resistor and is at a low level, so that the output end outputs the second level control signal which is a low-level signal, and the first switch tube and the second switch tube are controlled to be turned off.

[0007] In one of the embodiments, the detection circuit further comprises a first diode, which is connected between the ground end and the output end of the detection circuit to suppress transient voltage.

[0008] In one of the embodiments, the protection circuit further comprises a second diode and a third diode, the second diode is connected between a second connection node and the ground end, and the third diode is connected between a third connection node and the ground end, wherein the second connection node is a connection node between the first switch tube and the first signal end, and the third connection node is a connection node between the second switch tube and the second signal end.

[0009] In one of the embodiments, the first switch tube and the second switch tube are both NMOS tubes, the first control end and the second control end are the gates of the NMOS tubes, the first connection end and the third connection end are the drains of the NMOS tubes, and the second connection end and the fourth connection end are the sources of the NMOS tubes.

[0010] In one of the embodiments, the protection circuit further comprises a third resistor and a fourth resistor, the third resistor is connected between the output end of the detection circuit and the first control end of the first switch tube, and the fourth resistor is connected between the output end of the detection circuit and the second control end of the second switch tube, so as to limit the current flowing into the first switch tube and the second switch tube.

[0011] In one of the embodiments, the protection circuit further comprises a fifth resistor and a sixth resistor, one end of the fifth resistor is connected with a high level end, and the other end is connected with the second connection end of the first switch tube, one end of the sixth resistor is connected with the high level end, and the other end is connected with the fourth connection end of the second switch tube, wherein the high level end is used for providing a high level voltage, and the fifth resistor and the sixth resistor are pull-up resistors used for providing high level bias for the first switch tube and the second switch tube.

[0012] In one of the embodiments, the power end of the quick connection interface is used for connecting a direct current voltage signal, the first signal end is a TX signal end, and the second signal end is a RX signal end; the first signal pin of the MCU is an USART0_TX pin, and the second signal pin of the MCU is an USART0_RX pin.

[0013] In a second aspect, a game device is provided, comprising a quick connection interface, an MCU and the protection circuit as described in the first aspect, wherein the protection circuit is arranged in the game device and connected between the quick connection interface and the MCU.

[0014] Therefore, the protection circuit of the application can effectively avoid high voltage or abnormal current flowing into the MCU pin when the quick connection interface is not correctly connected (the power end is not connected with the power supply) and the first switch tube and the second switch tube are disconnected, prevent the MCU from being damaged due to overvoltage and overcurrent, and improve the safety of the MCU operation; at the same time, the signal path is only conducted when the power end N1 of the quick connection interface 200 is normally connected (the interface is correctly connected), which reduces the signal interference and false triggering in the unstable connection stage of the interface, and ensures the stability of the signal transmission between the quick connection interface and the MCU. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0016] Figure 1Structure diagram of a protection circuit in some embodiments of the present application; Figure 2 Structure diagram of another protection circuit in some embodiments of the present application; Figure 3 Circuit structure diagram of a detection circuit in some embodiments of the present application; Figure 4 Structure diagram of another protection circuit in some embodiments of the present application; Figure 5 Circuit structure diagram of a protection circuit in some embodiments of the present application; Figure 6 Structure diagram of another protection circuit in some embodiments of the present application; Figure 7 Structure diagram of another protection circuit in some embodiments of the present application; Figure 8 Structure block diagram of a game device in some embodiments of the present application; Figure 9 Structure diagram of a connecting surface of a steering wheel and a base in some embodiments of the present application. DETAILED DESCRIPTION

[0017] In order to enable persons skilled in the art to better understand the schemes of the present application, the technical schemes in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative labor fall within the scope of protection of the present application.

[0018] The terms “first”, “second”, and the like in the specification of the present application, the claims, and the above-described drawings are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms “include” and “have” and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product, or device.

[0019] In this document, the phrase “embodiment” means that the specific features, structures, or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment is referred to, nor does it mean that independent or alternative embodiments are mutually exclusive or alternative to each other. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0020] Referring to Figure 1 , Figure 1 Fig. 1 is a schematic diagram of a protection circuit according to some embodiments of the present application. In some embodiments, the protection circuit 100 is configured to be connected between a fast interface 200 and a MCU (Microcontroller Unit) 300. The fast interface 200 includes a power terminal N1 and a signal terminal, which includes a first signal terminal S1 and a second signal terminal S2. The protection circuit 100 includes a detection circuit 110, a first switch tube 120 and a second switch tube 130. The detection circuit 110 includes an input terminal N2 and an output terminal N3. The input terminal N2 is configured to be connected to the power terminal N1 of the fast interface 200. The detection circuit 110 is configured to output a corresponding control signal through the output terminal N3 in response to a voltage connection state of the power terminal N1 of the fast interface 200. The control signal includes a first level control signal and a second level control signal. The first switch tube 120 is configured to be connected between the first signal terminal S1 and the MCU 300. The second switch tube 130 is configured to be connected between the second signal terminal S2 and the MCU 300.

[0021] In some embodiments, the first switch tube 120 and the second switch tube 130 are also connected to the output terminal N3 of the detection circuit 110. When the power terminal N1 of the fast interface 200 is connected to a power signal, the detection circuit 110 outputs the first level control signal through the output terminal N3. The first switch tube 120 and the second switch tube 130 are turned on in response to the first level control signal, thereby turning on the connection between the first signal terminal S1, the second signal terminal S2 and the MCU 300. When the power terminal N1 of the fast interface 200 is not connected to a power signal, the detection circuit 110 outputs the second level control signal through the output terminal N3. The first switch tube 120 and the second switch tube 130 are turned off in response to the second level control signal, thereby turning off the connection between the first signal terminal S1, the second signal terminal S2 and the MCU 300.

[0022] The protection circuit 100 is used for connecting the quick connection interface 200 and the MCU 300 to realize protection of the MCU. The quick connection interface 200 is provided with a power supply end N1 and a first signal end S1 and a second signal end S2 for transmitting signals. The protection circuit 100 comprises a detection circuit 110, a first switch tube 120 and a second switch tube 130. The input end N2 of the detection circuit 110 is connected with the power supply end N1 of the quick connection interface 200, and is used for detecting whether the power supply end N1 is connected with a power supply signal in real time. When the power supply end N1 of the quick connection interface 200 is connected with the power supply signal, the detection circuit 110 receives the power supply signal of the power supply end N1, and outputs a first level control signal through the output end N3. When the power supply end N1 is not connected with the power supply signal, the detection circuit 110 outputs a second level control signal.

[0023] The first switch tube 120 is connected between the first signal end S1 of the quick connection interface 200 and the MCU 300, and the second switch tube 130 is connected between the second signal end S2 and the MCU 300. The control ends of the first switch tube 120 and the second switch tube 130 are connected with the output end N3 of the detection circuit 110 to receive the control signal. When the detection circuit 110 outputs the first level control signal, the first switch tube 120 and the second switch tube 130 are turned on in response to the signal, so that the first signal end S1 and the second signal end S2 of the quick connection interface 200 form a conduction path with the corresponding signal pins of the MCU 300, to ensure normal transmission of the signals. When the detection circuit 110 outputs the second level control signal, the first switch tube 120 and the second switch tube 130 are turned off in response to the signal, to cut off the path between the first signal end S1, the second signal end S2 and the MCU 300.

[0024] Therefore, when the quick connection interface 200 is not correctly connected (for example, the power supply end N1 is not connected with the power supply, and at this time, the signal end may be incorrectly connected with the power supply), the first switch tube 120 and the second switch tube 130 are turned off, which can effectively avoid that the signal end of the quick connection interface 200 is incorrectly connected with the power supply, for example, is incorrectly connected with high voltage or abnormal current and is conducted to the MCU pin, to prevent the MCU from being damaged due to overvoltage and overcurrent, and to improve the safety of the MCU operation. At the same time, the signal path is only conducted when the power supply end N1 of the quick connection interface 200 is normally connected (the interface is correctly connected), to reduce the signal interference and the false triggering in the stage when the interface is not correctly connected, and to ensure the stability of the signal transmission between the quick connection interface and the MCU.

[0025] Wherein, taking the connection between the steering wheel and the base as an example, the docking of the two is initially assembled through the quick release structure (such as the quick release buckle and the clamping structure are clamped, etc.), and then rotated by a certain angle to a preset locking position (for example, clockwise rotation by 15° until the quick release structure is clamped in place), at this time the power terminal N1 and the signal terminal are completely aligned and conductive, and the quick connection interface 200 is correctly docked. However, incorrect docking includes only initial assembly but no rotation, or insufficient rotation angle without triggering the lock, etc., resulting in misalignment of the contact points, i.e. the quick connection interface 200 is not correctly docked.

[0026] Please refer to Figure 2 , Figure 2 Another structure diagram of the protection circuit in some embodiments of the present application, in some embodiments, the first switch tube 120 includes a first connection end C1, a second connection end C2, and a first control end C3, the second switch tube 130 includes a third connection end C4, a fourth connection end C5, and a second control end C6, the first connection end C1 of the first switch tube 120 is connected with the first signal end S1 of the quick connection interface 200, the second connection end C2 of the first switch tube 120 is connected with the first signal pin S3 of the MCU 300, the third connection end C4 of the second switch tube 130 is connected with the second signal end S2 of the quick connection interface 200, the fourth connection end C5 of the second switch tube 130 is connected with the second signal pin S4 of the MCU 300, the first control end C3 of the first switch tube 120 and the second control end C6 of the second switch tube 130 are both connected with the output end N3 of the detection circuit 110, and the first switch tube 120 and the second switch tube 130 are respectively in the on or off state in response to the corresponding control signals received by the first control end C3 and the second control end C6.

[0027] Wherein, the first switch tube 120 is provided with a first connection end C1, a second connection end C2, and a first control end C3, wherein the first connection end C1 is connected with the first signal end S1 of the quick connection interface 200 for accessing the signal on the side of the quick connection interface 200; the second connection end C2 is connected with the first signal pin S3 of the MCU 300 for transmitting the signal to the MCU 300; the first control end C3 receives the control signal of the detection circuit 110 to control the on-off of the first connection end C1 and the second connection end C2. The second switch tube 130 is provided with a third connection end C4, a fourth connection end C5, and a second control end C6, wherein the third connection end C4 is connected with the second signal end S2 of the quick connection interface 200, the fourth connection end C5 is connected with the second signal pin S4 of the MCU 300, and the second control end C6 is connected with the first control end C3 of the first switch tube 120 to commonly connect the output end N3 of the detection circuit 110 to synchronously receive the control signal to control the on-off of the third connection end C4 and the fourth connection end C5.

[0028] Thus, when the power terminal N1 of the fast interface 200 is connected to the power signal, the detection circuit 110 outputs the first level control signal, and the first control terminal C3 of the first switch tube 120 and the second control terminal C6 of the second switch tube 130 synchronously receive the signal, so that the first switch tube 120 and the second switch tube 130 are turned on, thereby forming a conduction path between the first signal terminal S1 and the second signal terminal S2 of the fast interface 200 and the first signal pin S3 and the second signal pin S4 of the MCU; when the power terminal N1 is not connected to the power signal, the detection circuit 110 outputs the second level control signal, and the two switch tubes are synchronously turned off, thereby cutting off the signal path between the fast interface and the MCU.

[0029] Thus, the control terminals of the first switch tube 120 and the second switch tube 130 synchronously receive the signal of the detection circuit, which ensures that the two signals (the signals corresponding to the first signal terminal S1 and the second signal terminal S2) can be turned on or turned off at the same time, avoids the problems such as signal transmission abnormality or protection failure caused by the asynchronization of the switch tubes, and further guarantees the consistency of the signal transmission between the MCU and the fast interface 200 and the working safety of the MCU.

[0030] Please refer to Figure 3 , Figure 3 The circuit structure diagram of the detection circuit in some embodiments of the present application is shown in FIG. 2. In some embodiments, the first switch tube 120 and the second switch tube 130 are high-level conduction switch tubes, the first level control signal is a high-level signal, the second level control signal is a low-level signal, the detection circuit 110 includes a first resistor R1 and a second resistor R2, the first resistor R1 and the second resistor R2 are connected in series between the input terminal N2 and the ground terminal GND, and a first connection node N4 of the first resistor R1 and the second resistor R2 is connected to the output terminal N3 of the detection circuit 110. In the present application, when the power terminal N1 of the fast interface 200 is connected to the power signal, the first connection node N4 is at a high level, so that the output terminal N3 outputs the first level control signal which is a high-level signal, thereby controlling the first switch tube 120 and the second switch tube 130 to be turned on; when the power terminal N1 of the fast interface 200 is not connected to the power signal, the first connection node N4 is grounded through the second resistor R2 and is at a low level, so that the output terminal N3 outputs the second level control signal which is a low-level signal, thereby controlling the first switch tube 120 and the second switch tube 130 to be turned off.

[0031] The first switch tube 120 and the second switch tube 130 are high-level conduction type switch tubes, triggered to be turned on by high level, and the first level control signal is high level and the second level control signal is low level. The detection circuit 110 is implemented by a voltage dividing circuit, which is specifically composed of a first resistor R1 and a second resistor R2. The first resistor R1 and the second resistor R2 are connected in series between an input end N2 (connected with a power supply end N1 of the fast connection interface 200) and a ground end GND of the detection circuit, and a connection node (a first connection node N4) of the first resistor R1 and the second resistor R2 is connected to an output end N3 of the detection circuit 110 and outputs the corresponding control signal.

[0032] Therefore, when the power supply end N1 of the fast connection interface 200 is connected to a power supply signal, the current flows from the input end N2 to the ground through the first resistor R1 and the second resistor R2, and the level of the first connection node N4 is determined by the voltage division ratio of the first resistor R1 and the second resistor R2, and is in a high level state, so that the output end N3 of the detection circuit 110 outputs the first level control signal of high level. Since the first switch tube 120 and the second switch tube 130 are high-level conduction type, they will be turned on in response to the high-level signal, so that the signal end of the fast connection interface 200 and the corresponding pin of the MCU 300 form a path. When the power supply end N1 of the fast connection interface 200 is not connected to the power supply signal, the input end N2 has no power supply input, the first connection node N4 is directly connected to the ground through the second resistor R2, and is in a low level state, so that the output end N3 of the detection circuit 110 outputs the second level control signal of low level. At this time, the first switch tube 120 and the second switch tube 130 of high-level conduction type will be turned off in response to the low-level signal, cutting off the signal path between the fast connection interface and the MCU 300.

[0033] Therefore, the detection circuit 110 can realize the functions of power supply connection detection and control signal output by only voltage dividing through the series connection of the first resistor R1 and the second resistor R2, without the need for complex integrated circuits or other devices, thereby reducing the design difficulty. At the same time, by reasonably designing the voltage division ratio of R1 and R2, the high and low levels matched with the switching tube conduction logic can be accurately output, so that the switching tube can be reliably turned on when the power supply is normal and reliably turned off when the power supply is missing, further ensuring the safety of the MCU.

[0034] Please continue to refer to Figure 3 In some embodiments, the detection circuit 110 further includes a first diode D1 connected between the ground end GND and the output end N3 of the detection circuit 110 to suppress transient voltage.

[0035] The first diode D1 is connected between the ground terminal GND and the output terminal N3 of the detection circuit 110, and functions to suppress the transient voltage that may occur at the output terminal N3. Thus, when the output terminal N3 has an abnormal transient high voltage (exceeding the safe voltage range of the control terminal of the switch tube) due to interference, the first diode D1 will rapidly reverse breakdown, discharging the transient high voltage through the ground terminal GND, so that the voltage at the output terminal N3 is clamped within the safe range, avoiding the direct effect of the transient voltage on the control terminal of the first switch tube 120 and the second switch tube 130.

[0036] Thus, by effectively suppressing the transient high voltage at the output terminal N3, the damage of the control terminal of the switch tube due to overvoltage is avoided, and the working reliability of the switch tube and the control accuracy of the protection circuit are ensured. At the same time, the transient voltage suppression is realized only by the diode, without introducing complex circuit structures, thereby improving the anti-interference ability of the circuit while reducing the complexity of the circuit.

[0037] The first diode D1 in the detection circuit 110 is a Zener diode, with the cathode connected to the output terminal N3 and the anode connected to the ground terminal GND. In the normal working scenario of the circuit, when the power supply terminal N1 of the fast connection interface 200 is connected to the power supply signal, the voltage level at the first connection node N4 is determined by the voltage division ratio after the voltage division by the first resistor R1 and the second resistor R2. If the voltage level is lower than 6.8V, the first diode D1 is in the reverse blocking state, without affecting the high-level control signal at the output terminal N3, thereby ensuring the normal conduction of the first switch tube 120 and the second switch tube 130. When the power supply terminal N1 is not connected to the power supply, the output terminal N3 is at low level, and the first diode D1 is forward biased, without interfering with the low-level control of the switch tube. When the voltage at the output terminal N3 exceeds the preset threshold value due to interference, the first diode D1 reversely breaks down, clamping the voltage at the output terminal at 6.8V, and the excess current is discharged to the ground through the voltage stabilizing tube, thereby avoiding the continuous rise of the voltage exceeding the voltage threshold of the control terminal of the first switch tube 120 and the second switch tube 130.

[0038] Please refer to Figure 4 , Figure 4 Fig. 4 is another structural schematic diagram of the protection circuit in some embodiments of the present application. In some embodiments, the protection circuit 100 further includes a second diode D2 and a third diode D3. The second diode D2 is connected between the second connection node N5 and the ground terminal GND, and the third diode D3 is connected between the third connection node N6 and the ground terminal GND. The second connection node N5 is the connection node between the first switch tube 120 and the first signal terminal S1, and the third connection node N6 is the connection node between the second switch tube 130 and the second signal terminal S2.

[0039] The second diode D2 is connected between a second connection node N5 and a ground terminal GND, wherein the second connection node N5 is a connection point between the first switch tube 120 and a first signal terminal S1 of the fast interface 200; and the third diode D3 is connected between a third connection node N6 and the ground terminal GND, wherein the third connection node N6 is a connection point between the second switch tube 130 and a second signal terminal S2 of the fast interface 200.

[0040] In the normal working scenario of the circuit (normal signals are transmitted through the first signal terminal S1 and the second signal terminal S2), the second diode D2 and the third diode D3 are in reverse blocking state, which does not affect the signal transmission from the first signal terminal S1 to the first switch tube 120 and from the second signal terminal S2 to the second switch tube 130, and ensures that the normal communication is not disturbed. In the scenario of abnormal high voltage at the signal terminal (such as electrostatic discharge), if abnormal high voltage is introduced through the first signal terminal S1, the voltage of the second connection node N5 rises suddenly, and when the voltage exceeds the forward conduction threshold of the second diode D2, the D2 is forward-biased to discharge the abnormal high voltage through the ground terminal GND, thereby avoiding the direct application of high voltage to the first connection terminal C1 of the first switch tube 120. Similarly, if abnormal high voltage is introduced through the second signal terminal S2, the third diode D3 is forward-biased to discharge the high voltage to the ground, thereby protecting the third connection terminal C4 of the second switch tube 130.

[0041] Therefore, for the abnormal high voltage (such as electrostatic discharge) that may be encountered at the signal terminal of the fast interface, the diode can directly discharge the high voltage to the ground before the signal enters the switch tube, thereby avoiding damage to the switch tube or the conduction of the high voltage to the MCU 300 through the switch tube, and complementing the on-off protection of the switch tube. In addition, the diode is in reverse blocking state under normal signal level, which does not affect the normal conduction of the signal, thereby ensuring the stability of the signal transmission between the fast interface and the MCU 300.

[0042] Please refer to Figure 5 , Figure 5 The circuit structure diagram of the protection circuit in some embodiments of the present application is shown in FIG. 1. In some embodiments, the first switch tube 120 and the second switch tube 130 are both NMOS tubes, as shown in FIG. 1. Figure 5 The first switch tube 120 is Q1, the second switch tube 130 is Q2, the first control terminal C3 and the second control terminal C6 are the gate of the NMOS tube, the first connection terminal C1 and the third connection terminal C4 are the drain of the NMOS tube, and the second connection terminal C2 and the fourth connection terminal C5 are the source of the NMOS tube.

[0043] The gate of the NMOS tube corresponds to the first control end C3 and the second control end C6, the drain corresponds to the first connection end C1 and the third connection end C4, and the source corresponds to the second connection end C2 and the fourth connection end C5. Thus, the drain (C1) of the first switch tube 120 (Q1) is connected with the first signal end S1 of the fast connection interface 200, and the source (C2) is connected with the first signal pin S3 of the MCU 300; the drain (C4) of the second switch tube 130 (Q2) is connected with the second signal end S2 of the fast connection interface 200, and the source (C5) is connected with the second signal pin S4 of the MCU 300; the gates (C3, C6) of Q1 and Q2 are connected with the output end N3 of the detection circuit 110 to receive the control signal.

[0044] The on-off characteristic of the NMOS tube is that the tube is turned on when the gate-source voltage (Vgs) is greater than the threshold voltage. When the power supply end N1 of the fast connection interface 200 is connected with the power supply signal, the detection circuit 110 outputs the first control signal with high level, which is applied to the gates of Q1 and Q2, so that the gate-source voltage meets the on-off condition (Vgs is greater than the threshold voltage), the drain and the source of Q1 and Q2 are turned on, the first signal end S1 and the second signal end S2 form the path with the corresponding pins of the MCU 300 through Q1 and Q2, and the signal transmission is realized; when the power supply end N1 is not connected with the power supply signal, the detection circuit 110 outputs the second control signal with low level, the gate-source voltage of Q1 and Q2 is insufficient, the drain and the source are cut off, and the signal path between the fast connection interface and the MCU 300 is cut off.

[0045] Thus, the high-level on-off characteristic of the NMOS tube matches the first control signal output by the detection circuit, and no additional level conversion circuit is needed to realize the control; and the resistance between the drain and the source of the NMOS tube is small when the tube is turned on, so that the signal attenuation in the transmission process is reduced, and the communication quality between the fast connection interface and the MCU is ensured.

[0046] Please refer to Figure 6 , Figure 6 It is another circuit structure schematic diagram of the protection circuit in some embodiments of the application. In some embodiments, the protection circuit 100 further includes a third resistor R3 and a fourth resistor R4. The third resistor R3 is connected between the output end N3 of the detection circuit 110 and the first control end C3 of the first switch tube 120, and the fourth resistor R4 is connected between the output end N3 of the detection circuit 110 and the second control end C6 of the second switch tube 130, to limit the current flowing into the first switch tube 120 and the second switch tube 130.

[0047] The third resistor R3 is connected in series between the output end N3 of the detection circuit 110 and the first control end C3 of the first switch tube 120, and the fourth resistor R4 is connected in series between the output end N3 of the detection circuit 110 and the second control end C6 of the second switch tube 130. When the detection circuit 110 outputs a high-level first control signal, the current flows from the output end N3 to the first control end C3 of the first switch tube 120 through R3 and to the second control end C6 of the second switch tube 130 through R4. R3 and R4 limit the size of the current, avoiding excessive current flowing into the control end. When there is a transient high voltage at the output end N3, R3 and R4 can reduce the transient current flowing into the gate through the current limiting effect, and cooperate with the voltage clamping function of the first diode D1 to further reduce the electrical stress borne by the control end, avoiding damage to the switch tube.

[0048] Therefore, by directly limiting the current flowing into the control end of the switch tube through the resistor, the damage of the control end caused by the abnormal output signal of the detection circuit is avoided. The resistor and the first diode D1 in the detection circuit form double protection. Under transient interference, the resistor limits the current and the diode clamps the voltage, which together form protection for the control end of the switch tube, further improving the overall anti-interference ability of the circuit.

[0049] Please refer to Figure 7 , Figure 7 Another circuit structure diagram of the protection circuit in some embodiments of the present application is shown. In some embodiments, the protection circuit 100 further includes a fifth resistor R5 and a sixth resistor R6. One end of the fifth resistor R5 is connected with a high-level end N7, and the other end is connected with the second connection end C2 of the first switch tube 120. One end of the sixth resistor R6 is connected with the high-level end N7, and the other end is connected with the fourth connection end C5 of the second switch tube 130. The high-level end N7 is used to provide a high-level voltage. The fifth resistor R5 and the sixth resistor R6 are pull-up resistors, which are used to provide high-level bias for the first switch tube 120 and the second switch tube 130.

[0050] The high-level end N7 is the level source of the pull-up resistor, which is used to provide a stable high-level that meets the signal logic of the MCU 300. The high-level end N7 can be directly connected with an external independent constant voltage source, such as a common VCC_3V3, etc. It can also obtain a stable high-level from an existing power supply through a voltage dividing circuit, so that an independent constant voltage source does not need to be introduced additionally, and the power supply of the fast connection interface can be reused, simplifying the circuit structure.

[0051] The fifth resistor R5 has one end connected with the high level terminal N7 and the other end connected with the second connection terminal C2 of the first switch tube 120. The sixth resistor R6 has one end connected with the high level terminal N7 and the other end connected with the fourth connection terminal C5 of the second switch tube 130. Thus, when the power supply terminal N1 of the quick connection interface 200 is connected with the power supply, the detection circuit outputs the high level to control the first switch tube 120 and the second switch tube 130 to be turned on, the fifth resistor and the sixth resistor will not interfere with the normal signal transmission. When the power supply terminal N1 of the quick connection interface is not connected with the power supply, the first switch tube 120 and the second switch tube 130 are turned off, the S3 and S4 pins of the MCU 300 are connected with the high level terminal N7 through the R5 and R6 and are forced to be pulled to the stable high level of the high level terminal, avoiding the MCU pin being triggered by mistake.

[0052] Thus, when the switch tube is turned off, the pull-up resistor forces the MCU pin to be pulled to the stable high level, avoiding the pin being interfered to generate the abnormal level. When the switch tube is turned on, the pull-up resistor will not change the normal level of the signal terminal, further improving the functionality of the protection circuit.

[0053] Please continue to refer to Figure 7 In some embodiments, the protection circuit 100 further comprises a seventh resistor R7 and an eighth resistor R8. The seventh resistor R7 is connected between the first connection terminal C1 of the first switch tube 120 and the first signal terminal S1 of the quick connection interface 200. The eighth resistor R8 is connected between the third connection terminal C4 of the second switch tube 130 and the second signal terminal S2 of the quick connection interface 200.

[0054] The seventh resistor R7 is connected in series between the first connection terminal C1 of the first switch tube 120 and the first signal terminal S1 of the quick connection interface 200. The eighth resistor R8 is connected in series between the third connection terminal C4 of the second switch tube 130 and the second signal terminal S2 of the quick connection interface 200. The R7 and R8 are usually small resistance resistors, which have negligible influence on the normal signal transmission and will not change the state of the signal, ensuring the integrity of the signal transmission between the quick connection interface and the MCU. In the scenario of abnormal current at the signal terminal, if the first signal terminal S1 introduces an abnormal large current, the current needs to pass through the R7 to reach the first connection terminal C1, and the R7 will reduce the current flowing into the first connection terminal C1 of the first switch tube 120 through the current limiting effect, avoiding the switch tube being damaged due to overcurrent. Similarly, the abnormal current introduced by the second signal terminal S2 will be limited by the R8 to protect the third connection terminal C4 of the second switch tube 130.

[0055] Therefore, when the abnormal current is introduced into the signal end, the resistance can directly limit the current size, avoid the damage of the switch tube drain caused by bearing too large current, and prolong the service life of the protection element; at the same time, the small resistance value is selected to ensure that the normal signal transmission is not disturbed, which not only meets the protection requirement, but also ensures the integrity of the signal transmission between the fast connection interface and the MCU.

[0056] In some embodiments, the power end N1 of the fast connection interface 200 is used to access a DC voltage signal, specifically a 12V DC voltage signal, the first signal end S1 is a TX signal end, and the second signal end S2 is a RX signal end; the first signal pin of the MCU 300 is a USART0_TX pin, and the second signal pin of the MCU 300 is a USART0_RX pin.

[0057] Among them, the power end N1 of the fast connection interface 200 is used to access a 12V DC voltage signal; the first signal end S1 is a TX signal end (i.e. a sending signal end, used to send data externally), and the second signal end S2 is a RX signal end (i.e. a receiving signal end, used to receive external data), which form a pair of serial communication signal ends, the first signal pin S3 of the MCU 300 is a USART0_TX pin, and the second signal pin S4 is a USART0_RX pin, which are respectively connected with the TX signal end (S1) and the RX signal end (S2) of the fast connection interface through the first switch tube 120 and the second switch tube 130.

[0058] Therefore, when the power end N1 of the fast connection interface 200 accesses a 12V DC voltage, the detection circuit 110 outputs a high-level control signal, the first switch tube 120 and the second switch tube 130 are turned on, the TX signal is transmitted to the USART0_TX pin of the MCU 300 through the first switch tube, the RX signal is transmitted to the USART0_RX pin of the MCU 300 through the second switch tube, and the normal transmission and reception of serial data is realized; when the power end N1 does not access a 12V voltage (such as the disconnection of the fast connection interface), the switch tube is turned off, and the connection between the TX and RX signals and the MCU serial port pins is cut off, avoiding the damage of the USART interface caused by abnormal voltage / current.

[0059] Therefore, the 12V DC power supply and the TX / RX serial signal are limited in a targeted manner, so that the protection circuit adapts to the actual application scenarios of most fast connection interfaces; and the USART serial port pin is the interface for communication between the MCU and external devices, and the protection circuit ensures that the serial port path is turned on only when the 12V power supply is normally accessed (the interface is correctly connected), which can prevent damage caused by the intrusion of the 12V power supply into the serial port pin when the fast connection interface is misaligned, and improve the working safety of the MCU serial port interface.

[0060] Please refer to Figure 8 , Figure 8A structural diagram of a game device in some embodiments of the present application, in some embodiments, the game device 400 comprises a quick connection interface 410, an MCU 420 and a protection circuit 100 as in any of the preceding embodiments, wherein the protection circuit 100 is arranged in the game device 400 and connected between the quick connection interface and the MCU.

[0061] In the game device 400, the quick connection interface 410 is an interface for connecting the game device 400 with an external device, including a power supply end N1, a first signal end S1 (such as a TX end) and a second signal end S2 (such as an RX end); the MCU realizes data transmission and reception through a first signal pin (such as USART0_TX) and a second signal pin (such as USART0_RX); and the protection circuit 100 is built-in in the game device 400, one end of which is connected with the quick connection interface and the other end of which is connected with the MCU.

[0062] In the game device 400, the quick connection interface 410 is an interface for connecting the game device 400 with an external device (such as a game base), including a power supply end N1 (receiving working power supplied by the base, such as 12V DC voltage), a first signal end S1 (TX end, transmitting game operation signal) and a second signal end S2 (RX end, receiving control signal fed back by the base); the MCU realizes data transmission and reception and processing through a first signal pin (such as USART0_TX) and a second signal pin (such as USART0_RX); and the protection circuit 100 is built-in in the game device 400, one end of which is connected with the quick connection interface and the other end of which is connected with the MCU, wherein an input end of a detection circuit of the protection circuit is connected with the power supply end N1 of the quick connection interface, and a switch tube is connected in series between the signal end and the MCU pin.

[0063] Therefore, when the game device 400 is correctly connected with the external base through the quick connection interface (such as completing the initial insertion and rotation locking of the quick release structure), the base inputs a power supply signal to the power supply end N1 of the quick connection interface, the detection circuit of the protection circuit outputs a first level control signal to drive the switch tube to be conductive, so that the TX / RX signal end is connected with the corresponding pin of the MCU, realizing normal transmission of the game operation signal; when the connection is not in place (such as insufficient rotation of the quick release structure or mispositioning of the contact), there is no power supply input to the power supply end N1, the detection circuit outputs a second level control signal, and the switch tube is disconnected, cutting off the connection between the signal end and the MCU, thereby avoiding damage of the MCU caused by erroneous contact of the signal end with the power supply.

[0064] Therefore, due to the frequent disassembly and assembly of the game device (such as a game steering wheel), the contact is prone to mispositioning during the rotation of the quick disassembly structure, which causes the signal end to be mistakenly connected to the power supply. The protection circuit avoids the flow of high-voltage signals into the MCU and the device failure caused by accidental contact by enabling the signal path through the power supply connection. This ensures that the MCU is always in a protected state during the entire docking of the game device 400 and the external device, thereby reducing the risk of damage during interface operation.

[0065] In some embodiments, the protection circuit 100 can also be applied to other devices, such as toys, vehicles, and the like. The quick connection interface 200 in the foregoing embodiments can be a quick connection interface in the other devices, and the MCU 300 in the foregoing embodiments can be an MCU in the other devices.

[0066] Please refer to Figure 9 , Figure 9 The connection surface of the steering wheel and the base in some embodiments of the present application is shown in the figure. In some embodiments, taking a game device as an example, the steering wheel is generally docked with an external base, and the two are connected through a quick connection structure for detachable connection. The steering wheel is internally integrated with a quick connection interface, an MCU, and a protection circuit 100. As shown in Figure 9 The connection surface of the quick connection interface is provided with a power end contact K1 (corresponding to a power end N1, receiving 12V power supply), a first signal end contact K2 (corresponding to an RX end S2), a second signal end contact K3 (corresponding to a TX end S1), and a GND contact K4. The base is provided with a corresponding docking interface, and the connection surface includes a docking power end contact M1, a docking first signal end contact M2, a docking second signal end contact M3, and a GND contact M4. Mechanical guide structures are designed on the connection surfaces of the two to limit the relative position and ensure accurate docking.

[0067] When the steering wheel is correctly docked with the base, the connection surfaces are fitted and docked under the action of the mechanical guide structure. The power end contact K1 is in contact with the docking power end contact M1, and the 12V power signal is transmitted to the power end N1 of the steering wheel. At the same time, the signal end contacts K2 / K3 are in contact with the docking signal end contacts M2 / M3, and the GND contacts K4 and M4 are conductive (realizing the common ground of the steering wheel and the base, ensuring the consistency of the ground potential of the two circuits, and ensuring the accuracy of signal identification). At this time, the detection circuit 110 of the protection circuit 100 detects the power signal and outputs a first level control signal to drive the first switch tube 120 and the second switch tube 130 to be conductive, so that the TX / RX signal end of the steering wheel is connected with the USART0_TX / USART0_RX pin of the MCU, realizing stable transmission of data.

[0068] When the steering wheel is separated from the base, the connecting surface contact is disconnected from the mechanical structure, the power supply end contact is disconnected, the power supply signal stops inputting, the detection circuit 110 outputs a second level control signal, the switch tube is immediately turned off, the connection between the signal end and the MCU is cut off, and the signal end contact, the GND contact and the mechanical guiding structure are also disconnected, so that the separation is completed.

[0069] Therefore, the transmission of the power supply signal is determined by whether the interface is correctly connected, avoiding the problems of mis-supplying power when the interface is not connected or still supplying power when the interface is separated, ensuring that the protection circuit 100 can accurately control the signal path based on the actual connection state, avoiding the protection failure caused by the mismatch between the power supply and the connection state; at the same time, the quick connection interface can cut off the power supply signal immediately when the interface is separated, so that the protection circuit quickly turns off the signal path, further improving the safety of the connection operation.

[0070] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments. The above describes the embodiments of the present application in detail, and the specific examples are applied to describe the principles and implementation modes of the present application. The above description of the embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed, and the above description of the embodiments should not be understood as the limitation of the present application. Any modification, equivalent replacement and improvement within the spirit and principles of the above embodiments should be included in the protection scope of the technical scheme.

Claims

1. A protection circuit, characterized in that, The protection circuit is used to connect between the quick-connect interface and the MCU. The quick-connect interface includes a power terminal and a signal terminal. The signal terminal includes a first signal terminal and a second signal terminal. The protection circuit includes: The detection circuit includes an input terminal and an output terminal. The input terminal is used to connect to the power supply terminal of the quick-connect interface. The detection circuit is used to respond to the voltage input status of the power supply terminal of the quick-connect interface and output a corresponding control signal through the output terminal. The control signal includes a first-level control signal and a second-level control signal. The first switching transistor is used to connect between the first signal terminal and the MCU; The second switching transistor is used to connect between the second signal terminal and the MCU; The first and second switching transistors are both connected to the output terminal of the detection circuit. When a power signal is connected to the power terminal of the quick-connect interface, the detection circuit outputs a first-level control signal through its output terminal. The first and second switching transistors turn on in response to the first-level control signal, thereby connecting the first and second signal terminals to the MCU. When no power signal is connected to the power terminal of the quick-connect interface, the detection circuit outputs a second-level control signal through its output terminal. The first and second switching transistors turn off in response to the second-level control signal, thereby disconnecting the first and second signal terminals from the MCU.

2. The protection circuit according to claim 1, characterized in that, The first switch includes a first connection terminal, a second connection terminal, and a first control terminal. The second switch includes a third connection terminal, a fourth connection terminal, and a second control terminal. The first connection terminal of the first switch is connected to the first signal terminal of the quick-connect interface. The second connection terminal of the first switch is connected to the first signal pin of the MCU. The third connection terminal of the second switch is connected to the second signal terminal of the quick-connect interface. The fourth terminal of the second switch is connected to the second signal pin of the MCU. The first control terminal of the first switch and the second control terminal of the second switch are both connected to the output terminal of the detection circuit.

3. The protection circuit according to claim 1, characterized in that, The first and second switching transistors are high-level turn-on switching transistors. The first level control signal is a high-level signal, and the second level control signal is a low-level signal. The detection circuit includes a first resistor and a second resistor, which are connected in series between the input terminal and the ground terminal. The first connection node of the first and second resistors is connected to the output terminal of the detection circuit. When a power signal is connected to the power supply terminal of the quick-connect interface, the first connection node is at a high level, thereby the output terminal outputs a high-level first level control signal, which controls the first and second switching transistors to turn on. When no power signal is connected to the power supply terminal of the quick-connect interface, the first connection node is grounded through the second resistor and is at a low level, thereby the output terminal outputs a low-level second level control signal, which controls the first and second switching transistors to turn off.

4. The protection circuit according to claim 1, characterized in that, The detection circuit also includes a first diode connected between the ground terminal and the output terminal of the detection circuit to suppress transient voltage.

5. The protection circuit according to claim 1, characterized in that, The protection circuit further includes a second diode and a third diode. The second diode is connected between the second connection node and the ground terminal, and the third diode is connected between the third connection node and the ground terminal. The second connection node is the connection node between the first switching transistor and the first signal terminal, and the third connection node is the connection node between the second switching transistor and the second signal terminal.

6. The protection circuit according to claim 2, characterized in that, Both the first and second switching transistors are NMOS transistors. The first and second control terminals are the gates of the NMOS transistors, the first and third connection terminals are the drains of the NMOS transistors, and the second and fourth connection terminals are the sources of the NMOS transistors.

7. The protection circuit according to claim 2, characterized in that, The protection circuit further includes a third resistor and a fourth resistor. The third resistor is connected between the output terminal of the detection circuit and the first control terminal of the first switching transistor, and the fourth resistor is connected between the output terminal of the detection circuit and the second control terminal of the second switching transistor, so as to limit the current flowing into the first switching transistor and the second switching transistor.

8. The protection circuit according to claim 2, characterized in that, The protection circuit further includes a fifth resistor and a sixth resistor. One end of the fifth resistor is connected to a high-level terminal, and the other end is connected to a second connection terminal of the first switching transistor. One end of the sixth resistor is connected to the high-level terminal, and the other end is connected to a fourth connection terminal of the second switching transistor. The high-level terminal is used to provide a high-level voltage, and the fifth and sixth resistors are pull-up resistors used to provide a high-level bias for the first and second switching transistors.

9. The protection circuit according to any one of claims 1-8, characterized in that, The power supply terminal of the quick-connect interface is used to receive a DC voltage signal. The first signal terminal is the TX signal terminal, and the second signal terminal is the RX signal terminal. The first signal pin of the MCU is the USART0_TX pin, and the second signal pin of the MCU is the USART0_RX pin.

10. A gaming device, characterized in that, It includes a quick-connect interface, an MCU, and a protection circuit as described in any one of claims 1-9, wherein the protection circuit is located within the gaming device and connected between the quick-connect interface and the MCU.

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