In-vehicle button state detection device

Abstract

A kind of vehicle-mounted key state detection device, comprising: key unit, contains different states;Detection unit is electrically connected to the key unit, for detecting the state of the key unit according to enable detection signal and output detection voltage;Control unit is electrically connected to the detection unit, for outputting the enable detection signal, and judging the current state of the key unit according to the detection voltage, so that user can know whether there is abnormal key in time. User cannot seek help in time in emergency.

Description

Technical Field

[0001] This invention relates to the field of vehicle networking technology, and in particular to an in-vehicle button status detection device and system. Background Technology

[0002] To meet user needs, cars are equipped with increasingly more functions. To ensure user safety, many cars are now equipped with TBOXes with ECALL functionality. When a vehicle encounters an emergency, such as a rollover or collision in a deserted area or on a highway, the ECALL function can automatically trigger an emergency call, or it can be triggered manually by pressing the SOS button. However, the bumps and vibrations during vehicle operation may cause the button interface to malfunction, resulting in the connection cable coming loose. This can cause the button to short-circuit, become detached, or become stuck, potentially preventing the emergency call from being triggered automatically or manually. This could prevent the driver from seeking timely assistance, delaying the process and potentially leading to serious injuries or fatalities. Summary of the Invention

[0003] In view of this, it is necessary to provide a button status detection device so that users can know in time whether the button is abnormal and users cannot seek help in time in an emergency.

[0004] One embodiment of the present invention provides a key state detection device, comprising:

[0005] The button unit includes different states;

[0006] A detection unit, electrically connected to the button unit, is used to detect the state of the button unit according to an enable detection signal and output a detection voltage.

[0007] The control unit is electrically connected to the detection unit and is used to output the enable detection signal and determine the current state of the button unit based on the detection voltage.

[0008] Preferably, the detection unit includes:

[0009] The first resistor has one end connected to the main voltage;

[0010] The second resistor has one end electrically connected to the other end of the first resistor and the other end electrically connected to the button unit;

[0011] The third resistor has one end electrically connected to the other end of the second resistor;

[0012] The first MOSFET has its gate electrically connected to the other end of the third resistor, its drain electrically connected to the common terminal of the second and third resistors, and its source outputting the detection voltage to the control unit through the fourth resistor.

[0013] The second MOSFET has its gate electrically connected to the control unit to receive the enable detection signal. The gate of the second MOSFET is also grounded through a fifth resistor, the source of the second MOSFET is grounded through a sixth resistor, and the drain of the second MOSFET is electrically connected to the gate of the first MOSFET.

[0014] Preferably, the button unit comprises:

[0015] The buttons have different states;

[0016] The first capacitor has one end connected to the button and the other end grounded.

[0017] Preferably, the state of the button includes any one of the following: shorted to the main voltage, shorted to ground, button floating, and normal connection.

[0018] Preferably, when the second MOSFET receives the enable detection signal, causing the second MOSFET to turn on and the first MOSFET to turn on, and when the voltage sampled by the control unit is a detection voltage within a first voltage range, the button is shorted to the main voltage.

[0019] Preferably, when the second MOSFET receives the enable detection signal, causing the second MOSFET to turn on and the first MOSFET to turn off, and when the voltage sampled by the control unit is the detection voltage within the second voltage range, the button is shorted to ground.

[0020] Preferably, when the second MOSFET receives the enable detection signal, causing the second MOSFET to turn on and the first MOSFET to turn on, and when the voltage sampled by the control unit is a detection voltage within the third voltage range, the button is in a floating state.

[0021] Preferably, when the second MOSFET receives the enable detection signal, causing the second MOSFET to turn on and the first MOSFET to turn on, and when the voltage sampled by the control unit is the detection voltage within the fourth voltage range, the button is in a normal connection state.

[0022] Preferably, the control unit is further configured to send the status of the button to the user terminal device.

[0023] Preferably, the enable detection signal is a low-level to high-level signal.

[0024] Compared to existing technologies, the button status detection device provided in this invention outputs an enable detection signal from the control unit, enabling the detection unit to detect the status of the button unit and output a detection voltage based on the enable detection signal. The control unit then determines the current status of the button unit based on the detection voltage output by the detection unit, allowing the user to promptly understand whether the button is malfunctioning and preventing the user from being unable to seek help in an emergency. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of a module of one embodiment of the button status detection device of the present invention;

[0026] Figure 2 This is a circuit diagram of one embodiment of the button status detection device of the present invention.

[0027] Explanation of main component symbols

[0028] 10: Button status detection device

[0029] 100: Button unit

[0030] 101: Detection Unit

[0031] 102: Control Unit

[0032] R1-R7: First resistor - Seventh resistor

[0033] Q1-Q2: First MOSFET - Second MOSFET

[0034] 16A, 16B: Electronic devices

[0035] V BAT Main voltage

[0036] V ADC Detection voltage

[0037] Key: Button

[0038] V Key Key voltage

[0039] Cr: Capacitor

[0040] C1: First capacitor

[0041] EN: Enable detection signal

[0042] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0044] In this document, the term "implementation" means that a specific feature, structure, or characteristic described in connection with an implementation may be included in at least one implementation of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same implementation, nor is it a separate or alternative implementation mutually exclusive with other implementations. It will be explicitly and implicitly understood by those skilled in the art that the implementations described herein can be combined with other implementations.

[0045] See Figure 1 As shown, Figure 1 This is a schematic diagram of a module of one embodiment of the button state detection device 10 of the present invention. In this embodiment, the button state detection device 10 can be applied to an automobile. Figure 1As shown, the button state detection device 10 includes a button unit 100, a detection unit 101, and a control unit 102. The button unit 100 has different states; in this embodiment, the button unit 100 can be in any of the following states: shorted to main voltage, shorted to ground, button floating, or normally connected. The detection unit 101 is electrically connected to the button unit 101 and is used to detect the state of the button unit 100 according to the enable detection signal EN and output a detection voltage. The control unit 102 is electrically connected to the detection unit 101 and is used to output the enable detection signal and determine the current state of the button unit 100 based on the detection voltage output by the detection unit 101. The enable detection signal is a low-level to high-level signal. The range of the detection voltage output by the detection unit 101 varies depending on the different states of the button unit 100: shorted to main voltage, shorted to ground, button floating, and normally connected. For example, when the detection voltage output by the detection unit 101 falls within the first voltage range, the control unit 102 determines that the current state of the button unit 100 is shorted to the main voltage; when the detection voltage output by the detection unit 101 falls within the second voltage range, the control unit 102 determines that the current state of the button unit 100 is shorted to ground; when the detection voltage output by the detection unit 101 falls within the third voltage range, the control unit 102 determines that the current state of the button unit 100 is that the button is floating; when the detection voltage output by the detection unit 101 falls within the first and fourth voltage ranges, the control unit 102 determines that the current state of the button unit 100 is that the connection is normal.

[0046] In this embodiment, the control unit 102 is also used to report the status of the button unit 100 to the user's terminal device, so that the user can know in a timely manner whether the car's buttons are working properly. The control unit 102 can also cyclically sample the detection voltage output by the detection unit 101 N times. When all N samples are abnormal, that is, when the button is shorted to the main voltage, shorted to ground, or floating, the control unit 102 reports the abnormal status to the user's terminal device. When all N samples are normal, that is, when the button is properly connected, the control unit 102 reports the normal status to the user's terminal device.

[0047] See Figure 2 As shown, Figure 2 This is a schematic diagram of another embodiment of the button state detection device 10 of the present invention. (See attached diagram.) Figure 2As shown, in this embodiment, the button state detection device 10 includes a button unit 100, a detection unit 101, and a control unit 102. Its working principle is similar to that of the above embodiment and will not be described again here. In this embodiment, the detection unit 101 includes a first resistor R1, a second resistor R2, a third resistor R3, a first MOSFET Q1, and a second MOSFET Q2. In this circuit, one end of the first resistor R1 is connected to the main voltage Vbat; one end of the second resistor R2 is electrically connected to the other end of the first resistor R1, and the other end is electrically connected to the button unit 100; one end of the third resistor R3 is electrically connected to the other end of the second resistor R2; the gate of the first MOSFET Q1 is electrically connected to the other end of the third resistor R3, the drain of the first MOSFET Q1 is electrically connected to the common terminal of the second resistor R2 and the third resistor R3, and the source of the first MOSFET Q1 outputs the detection voltage to the control unit 102 through the fourth resistor R4, that is, one end of the fourth resistor R4 serves as the output terminal to output the detection voltage to the control unit 102; the gate of the second MOSFET Q2 is electrically connected to the control unit 102 to receive the enable detection signal, the gate of the second MOSFET Q2 is also grounded through the fifth resistor R5, the source of the second MOSFET Q2 is grounded through the sixth resistor R6, and the drain of the second MOSFET Q2 is electrically connected to the gate of the first MOSFET Q1. The detection unit 101 may further include a seventh resistor R7 and a capacitor Cr. One end of the seventh resistor R7 is electrically connected between the fourth resistor R4 and the control unit 102, and the capacitor Cr is connected in parallel with the seventh resistor R7. In this embodiment, the control unit 102 may include an analog-to-digital converter (ADC) to sample the output voltage of the detection unit 101, that is, to sample the voltage divided by the fourth resistor R4 and the seventh resistor R7.

[0048] In this embodiment, the button unit 100 includes a button Key and a first capacitor C1. The button Key has different states, such as being shorted to the main voltage, shorted to ground, floating, or in a normal connection state. The first capacitor C1 has one end connected to the button Key and the other end grounded. It is understood that there can be multiple button units 100, and this is not limited here.

[0049] In this embodiment, when the second MOSFET Q2 receives the enable detection signal EN, causing both the second MOSFET Q2 and the first MOSFET Q1 to turn on, the control unit 102 samples the voltage divided by the fourth resistor R4 and the seventh resistor R7 within the first voltage range (the sampling time is time t after the control unit 102 starts timing from when the output enable detection signal changes from low to high level; the formula for t is given below). The control unit 102 determines that the state of the button Key is shorted to the main voltage VBAT, meaning that the external connection of the button Key is normal, but the button Key is shorted to the main voltage VAT.BAT Specifically, the button voltage V KEY =V BAT Output voltage V ADC =V BAT *R7 / (R4+R7).

[0050] In this embodiment, when the second MOSFET Q2 receives the enable detection signal EN, causing it to turn on and the first MOSFET Q1 to turn off, the control unit 102 samples the voltage divided by the fourth resistor R4 and the seventh resistor R7 within the second voltage range (the sampling time is time t after the control unit 102 starts timing from when the output enable detection signal changes from low to high level; the formula for t is given below). The control unit 102 determines that the state of the button Key is shorted to ground, meaning the external connection of the button Key is normal, but the button Key is shorted to ground. Specifically, VKEY = 0, MOSFET Q1 is not turned on, and the output voltage V... ADC =0.

[0051] In this embodiment, when the second MOSFET Q2 receives the enable detection signal, causing both the second MOSFET Q2 and the first MOSFET Q1 to turn on, and the voltage sampled by the ADC of the control unit 102 from the voltage divider voltage of the fourth resistor R4 and the seventh resistor R7 is within the third voltage range (the sampling time is time t after the control unit 102 starts timing from when the output enable detection signal changes from low to high level; the formula for calculating t is given below), the control unit 102 determines that the state of the key button is floating. Specifically,

[0052] V KEY =V BAT *R' / (R1+R2+R'),R'=(R3+R6)*(R4+R7) / (R3+R4+R6+R7)

[0053] V ADC =V KEY *R6 / (R4+R7)

[0054] =V BAT *(R3+R6)*(R4+R7)*R7 / [(R1+R2+(R3+R6)*(R4+R7))*(R4+R7)]

[0055] In this embodiment, when the second MOSFET Q2 receives the enable detection signal, it causes both the second MOSFET Q2 and the first MOSFET Q1 to turn on. However, at this time, due to the presence of the first capacitor C1, V... KEY The point voltage cannot change abruptly, V KEY Voltage from the initial V BAT The discharge slowly decreases through R' until it reaches V. KEY =VBAT *R' / (R1+R2+R'), where R'=(R3+R6)*(R4+R7) / (R3+R4+R6+R7). The control unit 102 starts timing from the output enable detection signal changing from low to high. After timing t, the ADC of the control unit 102 starts sampling the voltage divided by the fourth resistor R4 and the seventh resistor R7. When the voltage is within the fourth voltage range, the control unit 102 determines that the key is connected normally. Specifically, the discharge time t of the first capacitor C1 is t=R'*C1*ln[(V1-V0) / (V1-Vt)], where V0 is the initial voltage value of the first capacitor C1, V1 is the final discharge voltage of the first capacitor C1, and Vt is the voltage value of the first capacitor C1 at time t (the optimal value of Vt is V). BAT and V KEY =V BAT The middle value of *R' / (R1+R2+R').

[0056] In one specific embodiment of the present invention, the resistance value of the first resistor R1 is 220K, the resistance value of the second resistor R2 is 0, the resistance value of the third resistor R3 is 220K, the resistance value of the fourth resistor R4 is 100K, the resistance value of the sixth resistor R6 is 180K, and the resistance value of the seventh resistor R7 is 30K. Then, when the key button is shorted to the main voltage V... BAT When the enable detection signal output by control unit 102 changes from low to high, the sampled voltage at time t falls within the first voltage range: 2.5V. <V ADC <3V; When the key is shorted to ground, the voltage sampled at time t after the enable detection signal output by the control unit 102 changes from low to high falls within the second voltage range: V ADC <0.3V; When the key is in a floating state, the voltage sampled at time t after the enable detection signal output by the control unit 102 changes from low to high falls within the third voltage range: 0.5V. <V ADC <1.3V; When the button Key is in the normal connection state, the voltage sampled at time t after the enable detection signal output by the control unit 102 changes from low to high falls within the fourth voltage range: 1.5V. <V ADC <2.3V.

[0057] Compared to existing technologies, the button status detection device provided in this invention outputs an enable detection signal from the control unit, enabling the detection unit to detect the status of the button unit and output a detection voltage based on the enable detection signal. The control unit then determines the current status of the button unit based on the detection voltage output by the detection unit, allowing the user to promptly understand whether the button is malfunctioning and preventing the user from being unable to seek help in an emergency.

[0058] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any appropriate changes and modifications made to the above embodiments within the essential spirit and scope of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A button status detection device, characterized in that, include: A button unit includes a button and a first capacitor. The button has different states. One end of the first capacitor is connected to the button, and the other end of the first capacitor is grounded. A detection unit, electrically connected to the button unit, is used to detect the state of the button unit according to an enable detection signal and output a detection voltage. A control unit, electrically connected to the detection unit, is used to output the enable detection signal and determine the current state of the button unit based on the detection voltage. The state of the button includes any one of the following: shorted to the main voltage, shorted to ground, button floating, and normal connection. The detection unit includes: The first resistor has one end connected to the main voltage; The second resistor has one end electrically connected to the other end of the first resistor and the other end electrically connected to the button unit; The third resistor has one end electrically connected to the other end of the second resistor; The first MOS transistor has its gate electrically connected to the other end of the third resistor, its drain electrically connected to the common terminal of the second resistor and the third resistor, and its source outputting the detection voltage to the control unit through the fourth resistor. The second MOSFET has its gate electrically connected to the control unit to receive the enable detection signal. The gate of the second MOSFET is also grounded through a fifth resistor, the source of the second MOSFET is grounded through a sixth resistor, and the drain of the second MOSFET is electrically connected to the gate of the first MOSFET.

2. The button status detection device as described in claim 1, characterized in that, When the second MOSFET receives the enable detection signal, the second MOSFET is turned on, the first MOSFET is turned on, and when the voltage sampled by the control unit is the detection voltage within the first voltage range, the button is shorted to the main voltage.

3. The button status detection device as described in claim 1, characterized in that, When the second MOSFET receives the enable detection signal, it turns on while the first MOSFET turns off. When the voltage sampled by the control unit is a detection voltage within the second voltage range, the button is shorted to ground.

4. The button status detection device as described in claim 1, characterized in that, When the second MOSFET receives the enable detection signal, the second MOSFET is turned on, the first MOSFET is turned on, and when the voltage sampled by the control unit is the detection voltage within the third voltage range, the button is in a floating state.

5. The button status detection device as described in claim 1, characterized in that, When the second MOSFET receives the enable detection signal, causing the second MOSFET to turn on, the first MOSFET to turn on, and when the voltage sampled by the control unit is the detection voltage within the fourth voltage range, the button is in a normal connection state.

6. The button state detection device according to any one of claims 1-5, characterized in that, The control unit is also used to send the status of the button to the user terminal device.

7. The button state detection device according to any one of claims 1-5, characterized in that, The enable detection signal is a low-level to high-level signal.

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