Automotive touch circuit device with electrostatic discharge protection

Abstract

A touch circuit device for a vehicle comprises an analog front-end circuit, a first memory, a second memory, a micro-control unit and an electrostatic discharge protector. The analog front-end circuit is provided with an electrostatic discharge detector which is used for detecting the automotive touch circuit device and outputting a detection result signal; the first memory stores a control parameter with a first debugging code, and correspondingly generates a first debugging signal according to the first debugging code; the second memory stores the touch data with a second debugging code, and correspondingly generates a second debugging signal according to the second debugging code; the micro-control unit generates a notification signal according to the control parameter and the touch data; when the detection result signal shows that no electrostatic discharge interference exists, the electrostatic discharge protector allows the notification signal to be output, and when the detection result signal shows that the electrostatic discharge interference exists and the debugging result represented by at least one of the first debugging signal and the second debugging signal is wrong, the electrostatic discharge protector forbids the notification signal to be output.

Description

Technical Field

[0001] The present invention relates to the technical field of touch circuit devices, and more particularly to a vehicle touch circuit device with electrostatic discharge protection. Background Art

[0002] With the advancement of touch technology, the application demand and market share of automotive touch panels have also increased year by year, and automotive touch products pay more attention to and have higher requirements for functional safety, especially for the vehicle central control screen composed of touch panels. Since it can control the vehicle's gear, lights, handbrake and other settings related to driving safety, if electrostatic discharge (ESD) interferes with the touch panel and causes a false touch event, it may seriously threaten the driving safety of vehicles on the road, which cannot meet the actual needs.

[0003] Therefore, there are still many deficiencies in the application of existing automotive touch panels, and there is a need for improvement. Summary of the invention

[0004] The main purpose of the present invention is to provide a touch circuit device for a vehicle with electrostatic discharge protection, which can realize electrostatic discharge protection of a touch panel for a vehicle with low cost and high reliability, prevent false touch events caused by electrostatic discharge interference, and thus realize a safer touch product.

[0005] To achieve the aforementioned objectives, the present invention provides a vehicle touch circuit device, which includes: an analog front-end circuit, receiving a touch input generated by a vehicle touch panel and outputting touch data accordingly, the analog front-end circuit having an electrostatic discharge detector for detecting the vehicle touch circuit device and outputting a detection result signal, the detection result signal representing whether electrostatic discharge interference occurs; a first storage, storing a control parameter for controlling the operation of the vehicle touch circuit device, the control parameter having a first error detection code, wherein a first error detection signal is generated in response to the first error detection code, the first error detection signal representing whether the error detection result according to the first error detection code is an error; a second storage, coupled to the analog front-end circuit, receiving and storing the touch data, the touch data having a second error detection code, wherein the second error detection code is used to detect the touch circuit device. A second debugging signal should be generated, and the second debugging signal represents whether the debugging result according to the second debugging code is an error; a micro control unit is coupled to the first storage and the second storage, and generates a notification signal according to the control parameter and the touch data; an electrostatic discharge protector is coupled to the electrostatic discharge detector, the first storage, the second storage and the micro control unit to receive the detection result signal, the first debugging signal, the second debugging signal and the notification signal respectively, wherein when the detection result signal shows that no electrostatic discharge interference occurs, the electrostatic discharge protector allows the notification signal to be output, and when the detection result signal shows that electrostatic discharge interference occurs and the debugging result represented by at least one of the first debugging signal and the second debugging signal is an error, the electrostatic discharge protector prohibits the notification signal from being output.

[0006] The above summary and the following detailed description are exemplary in nature and are intended to further illustrate the claims of the present invention. Other objects and advantages of the present invention will be described in the subsequent description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 The schematic diagram schematically shows a vehicle central control system using the vehicle touch circuit device with electrostatic discharge protection of the present invention.

[0008] Figure 2 A schematic diagram showing a vehicle touch control circuit device with electrostatic discharge protection according to the present invention.

[0009] Figure 3A A truth table is shown corresponding to a combinational logic circuit used to implement an ESD protector.

[0010] Figure 3B A combinational logic circuit diagram of an electrostatic discharge protector according to an embodiment of the present invention is shown.

[0011] Explanation of symbols:

[0012] Car touch panel 10

[0013] Automotive touch circuit device 20

[0014] Terminal host 30

[0015] Vehicle equipment31

[0016] Analog front end circuit 21

[0017] First storage 22

[0018] Second storage 23

[0019] Micro control unit 24

[0020] Electrostatic discharge protector 25

[0021] Data transmission interface 26

[0022] Electrostatic Discharge Detector 211

[0023] Data bus 29

[0024] First logic OR gate 31

[0025] The second logic OR gate 32

[0026] Logical Mutex OR Gate 33

[0027] Logic AND Gate 34 DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the implementation of the present invention and are not intended to limit the present invention.

[0029] Figure 1 The schematic diagram of the vehicle central control system using the vehicle touch circuit device with electrostatic discharge protection of the present invention is schematically shown, wherein the vehicle central control system includes a vehicle touch panel 10, a vehicle touch circuit device 20 and a terminal host 30. The vehicle touch panel 10 can be used for the driver or passenger of the vehicle to perform touch operations to control the settings of the vehicle, such as but not limited to gear settings, light settings, handbrake settings, etc. The vehicle touch circuit device 20 is coupled to the vehicle touch panel 10 to control the terminal host 30 accordingly according to the touch operation performed on the vehicle touch panel 10. The terminal host 30 is electrically connected to at least one vehicle device 31, such as but not limited to gear devices, light devices, handbrake devices, etc., so as to control at least one vehicle device 31 according to the touch operation performed on the vehicle touch panel 10.

[0030] Figure 2A schematic diagram showing the vehicle touch circuit device with electrostatic discharge protection of the present invention. Among them, the vehicle touch circuit device 20 includes an analog front-end circuit 21, a first memory 22, a second memory 23, a microcontroller unit 24, an electrostatic discharge protector 25, and a data transmission interface 26. The aforementioned analog front-end circuit 21 is used to receive the touch input generated by the vehicle touch panel 10 according to the touch operations performed by the driver or passengers, and output touch data based on this touch input. The aforementioned first memory 22 stores control parameters for controlling the operation of the vehicle touch circuit device 20. The aforementioned second memory 23 is coupled to the analog front-end circuit 21 to receive and store touch data. The aforementioned microcontroller unit 24 is coupled to the first memory 22 and the second memory 23, and according to the touch scan behavior mode of the vehicle touch circuit device 20 represented by the control parameters, reads the touch data from the second memory 23 and performs corresponding arithmetic processing, calculates the touch coordinates, writes the touch coordinates back to the second memory 23, and then sends a notification signal INT to the terminal host 30. When receiving the notification signal, the terminal host 30 then obtains the touch coordinates via the data transmission interface 26, and thus can complete a processing flow of touch data. Among them, the data transmission interface 26 can be a serial interface such as a Serial Peripheral Interface Bus (SPI) or an Inter-Integrated Circuit Bus (I2C), but this is only an example and not a limitation.

[0031] To provide the function of electrostatic discharge protection, the aforementioned analog front-end circuit 21 further has an electrostatic discharge detector 211, which is used to detect the vehicle touch circuit device 20 and output a detection result signal ESDD. The detection result signal ESDD represents whether there is an electrostatic discharge interference. In an embodiment, the electrostatic discharge detector 211 is an analog detection circuit, which is used to detect the working voltage WV of the vehicle touch circuit device 20. When the detected working voltage VW is higher than a default upper critical voltage TH1 or lower than a default lower critical voltage TH2 (that is, WV>TH1 or WV<TH2), the output detection result signal ESDD indicates that there is an electrostatic discharge interference. Among them, the upper critical voltage TH1 is greater than the lower critical voltage TH2. The detection result signal ESDD being 1 can indicate that there is an electrostatic discharge interference, and the detection result signal ESDD being 0 can indicate that there is no electrostatic discharge interference.

[0032] Furthermore, in one embodiment, the first storage 22 is a register, and the control parameter stored therein has a first debugging code, wherein a first debugging signal CS1 can be generated according to the first debugging code, and the first debugging signal CS1 represents whether the debugging result according to the first debugging code is an error, and the second storage 23 is a static random access memory (SRAM), and the touch data stored therein has a second debugging code, wherein a second debugging signal CS2 can be generated according to the second debugging code, and the second debugging signal CS2 represents whether the debugging result according to the second debugging code is an error.

[0033] The first error detection code or the second error detection code may be any mechanism that can detect whether the data is erroneous, such as a checksum, a parity check, etc. In one embodiment, the first error detection code and the second error detection code are both checksums. That is, in the automotive touch control circuit device 20, the first error detection code is generated by dividing the control parameter into K small blocks of data, and then adding all the values ​​of each small block of data to obtain a number, and then taking the 1's complement to obtain the first error detection code. The first error detection signal CS1 is generated by adding all the values ​​of all the K small blocks of data and adding the first error detection code, and then taking the 1's complement to obtain the first error detection signal CS1. If the result is 0, it means that the error detection signal CS1 is erroneous. The error detection result is no error, and the result is 1, which indicates that the error detection result is an error; similarly, the second error detection code is generated by dividing the aforementioned touch data into K small blocks of data, and then adding all the values ​​of each small block of data to obtain a number, and then taking the 1's complement of the number to obtain the second error detection code, and the second error detection signal CS2 is generated by adding all the values ​​in all K small blocks of data and adding the second error detection code, and then taking the 1's complement of the number to obtain the second error detection signal CS2. If the result is 0, it means that the error detection result is no error, and the result is 1, which indicates that the error detection result is an error.

[0034] The aforementioned micro control unit 24, data transmission interface 24, first storage 22 and second storage 23 are coupled together via a data bus 29. Therefore, the micro control unit 24 can access the first storage 22 and the second storage 23 via the data bus 29 to generate a notification signal INT according to the control parameters and touch data.

[0035] The electrostatic discharge protector 25 is coupled to the electrostatic discharge detector 211, the first storage 22, the second storage 23 and the micro control unit 24 to receive the detection result signal ESDD, the first error detection signal CS1, the second error detection signal CS2 and the notification signal INT respectively. When the detection result signal ESDD shows that no electrostatic discharge interference occurs, the electrostatic discharge protector 25 allows the notification signal INT to be output to the terminal host 30 to notify the terminal host 30 to receive the touch coordinate data ( Figure 2When the detection result signal ESDD indicates that electrostatic discharge interference occurs and the debugging result represented by at least one of the first debugging signal CS1 and the second debugging signal CS2 is an error, the electrostatic discharge protector 25 prohibits the notification signal INT from being output to the terminal host 30.

[0036] The terminal host 30 is electrically connected to at least one vehicle device 31. The data transmission interface 26 can access the touch coordinates generated by the micro control unit 24 based on the control parameters and touch data via the data bus 29, and transmit the touch coordinates to the terminal host 30. Therefore, the terminal host 30 can control the operation of the vehicle device 31 based on the touch coordinates.

[0037] Furthermore, since the aforementioned electrostatic discharge protector 25 determines whether to allow or prohibit the output of the notification signal INT according to the values ​​of the detection result signal ESDD, the first error detection signal CS1, and the second error detection signal CS2, the logical relationship between the notification signal INTP output by the electrostatic discharge protector 25 and the detection result signal ESDD, the first error detection signal CS1, the second error detection signal CS2, and the notification signal INT input to the electrostatic discharge protector 25 can be realized by only a combinational logic circuit, such as Figure 3A The truth table shown shows that the logical relationship is:

[0038] When (INT, CS1, CS2, ESDD) is (0, 0, 0, 0), INTP is 0,

[0039] When (INT, CS1, CS2, ESDD) is (0, 0, 0, 1), INTP is 0,

[0040] When (INT, CS1, CS2, ESDD) is (0, 0, 1, 0), INTP is 0,

[0041] When (INT, CS1, CS2, ESDD) is (0, 0, 1, 1), INTP is 0,

[0042] When (INT, CS1, CS2, ESDD) is (0, 1, 0, 0), INTP is 0,

[0043] When (INT, CS1, CS2, ESDD) is (0, 1, 0, 1), INTP is 0,

[0044] When (INT, CS1, CS2, ESDD) is (0, 1, 1, 0), INTP is 0,

[0045] When (INT, CS1, CS2, ESDD) is (0, 1, 1, 1), INTP is 0,

[0046] When (INT, CS1, CS2, ESDD) is (1, 0, 0, 0), INTP is 1,

[0047] When (INT, CS1, CS2, ESDD) is (1, 0, 0, 1), INTP is 0,

[0048] When (INT, CS1, CS2, ESDD) is (1, 0, 1, 0), INTP is 0,

[0049] When (INT, CS1, CS2, ESDD) is (1, 0, 1, 1), INTP is 0,

[0050] When (INT, CS1, CS2, ESDD) is (1, 1, 0, 0), INTP is 0,

[0051] When (INT, CS1, CS2, ESDD) is (1, 1, 0, 1), INTP is 0,

[0052] When (INT, CS1, CS2, ESDD) is (1, 1, 1, 0), INTP is 0,

[0053] When (INT, CS1, CS2, ESDD) is (1,1,1,1), INTP is 0,

[0054] Wherein, INT represents the input notification signal, CS1 represents the first error detection signal, CS2 represents the second error detection signal, ESDD represents the detection result signal, INTP represents the output notification signal, INT is 1, indicating that the input notification signal is valid, INT is 0, indicating that the input notification signal is invalid, CS1 is 1, indicating that the error detection result of the first error detection code is an error, CS1 is 0, indicating that the error detection result of the first error detection code is not an error, CS2 is 1, indicating that the error detection result of the second error detection code is an error, CS2 is 0, indicating that the error detection result of the second error detection code is not an error, ESDD is 1, indicating that electrostatic discharge interference occurs, ESDD is 0, indicating that no electrostatic discharge interference occurs, INTP is 1, indicating that the output notification signal is valid, and INTP is 0, indicating that the output notification signal is invalid.

[0055] Figure 3BThe combinational logic circuit diagram of the electrostatic discharge protector according to an embodiment of the present invention is shown. The electrostatic discharge protector described above is implemented by logic gates. The electrostatic discharge protector 25 includes a first logic OR gate (OR) 31, a second logic OR gate (OR) 32, a logic exclusive OR gate (XOR) 33 and a logic AND gate (AND) 34. The first logic OR gate 31 has an output terminal and two input terminals respectively connected to the first error detection signal CS1 and the second error detection signal CS2. The second logic OR gate 32 has an output terminal and two input terminals respectively connected to the detection result signal ESDD and the output terminal of the first logic OR gate 31. The logic exclusive OR gate 33 has an output terminal and two input terminals respectively connected to the input notification signal INT and the output terminal of the second logic OR gate 32. The logic AND gate 34 has two input terminals respectively connected to the input notification signal INT and the output terminal of the logic exclusive OR gate 33, and an output terminal for generating the output notification signal INTP. With this combinational logic circuit of the electrostatic discharge protector 25, the combinational logic circuit can be implemented by logic gates only. Figure 3A The logical relationship shown in the truth table achieves electrostatic discharge protection for automotive touch panels at low cost and high reliability.

[0056] The above embodiments are merely examples for the convenience of description. The scope of rights claimed by the present invention should be based on the claims, but not limited to the above embodiments.

Claims

1. A touch circuit device for a vehicle, characterized in that: include: an analog front-end circuit, receiving a touch input generated by a vehicle touch panel and outputting touch data accordingly, the analog front-end circuit having an electrostatic discharge detector for detecting the vehicle touch circuit device and outputting a detection result signal, the detection result signal indicating whether electrostatic discharge interference occurs; A first storage device stores a control parameter for controlling the operation of the vehicle touch circuit device, wherein the control parameter has a first debugging code, wherein a first debugging signal is generated in response to the first debugging code, and the first debugging signal indicates whether the debugging result according to the first debugging code is an error; A second storage device coupled to the analog front-end circuit receives and stores the touch data, wherein the touch data has a second debugging code, wherein a second debugging signal is generated in accordance with the second debugging code, and the second debugging signal indicates whether the debugging result according to the second debugging code is an error; A micro control unit is coupled to the first storage and the second storage, and generates a notification signal according to the control parameter and the touch data; an electrostatic discharge protector coupled to the electrostatic discharge detector, the first storage, the second storage and the micro control unit to receive the detection result signal, the first debugging signal, the second debugging signal and the notification signal respectively; When the detection result signal shows that no electrostatic discharge interference occurs, the electrostatic discharge protector allows the notification signal to be output; when the detection result signal shows that electrostatic discharge interference occurs and the debugging result represented by at least one of the first debugging signal and the second debugging signal is an error, the electrostatic discharge protector prohibits the notification signal from being output.

2. The vehicle touch circuit device according to claim 1, wherein: The first error detection code is a checksum, and the second error detection code is a checksum.

3. The vehicle touch circuit device according to claim 1, wherein: The electrostatic discharge detector is an analog detection circuit for detecting the operating voltage of the automotive touch circuit device, and when the detected operating voltage is higher than a default upper threshold voltage or lower than a default lower threshold voltage, the output detection result signal indicates that electrostatic discharge interference occurs.

4. The vehicle touch circuit device according to claim 1, wherein: The notification signal is used to be output to a terminal host, and the terminal host is electrically connected to and controls at least one vehicle device.

5. The vehicle touch circuit device according to claim 4, wherein: It further includes a data transmission interface, wherein the micro control unit generates a touch coordinate according to the control parameter and the touch data, and the transmission interface is used to transmit the touch coordinate to the terminal host.

6. The vehicle touch circuit device according to claim 5, wherein: The micro control unit, the data transmission interface, the first storage and the second storage are coupled together via a data bus.

7. The vehicle touch circuit device according to claim 1, wherein: The first storage is a buffer, and the control parameter stored therein represents the touch scanning behavior mode of the vehicle touch circuit device.

8. The vehicle touch circuit device according to claim 1, wherein: The second storage is a static random access memory.

9. The vehicle touch circuit device according to claim 1, wherein: The electrostatic discharge protector is a combinational logic circuit for realizing the logic relationship between the notification signal output by the electrostatic discharge protector and the detection result signal, the first error detection signal, the second error detection signal and the notification signal input to the electrostatic discharge protector.

10. The vehicle touch circuit device according to claim 9, characterized in that: The logical relationship is: when (INT, CS1, CS2, ESDD) is (0,0,0,0), (0,0,0,1), (0,0,1,0), (0,0,1,1), (0,1,0,0), (0,1,0,1), (0,1,1,0), (0,1,1,1), (1,0,0,0), (1,0,0,1), (1,0,1,0), (1,0,1,1), (1,1,0,0), (1,1,0,1), (1,1,0,0), (1,1,0,1), (1,1,1,0), (1,1,1,1), respectively, INTP is 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, where INT represents the input notification signal and CS1 represents the input notification signal. CS1 represents the first error detection signal, CS2 represents the second error detection signal, ESDD represents the detection result signal, INTP represents the output notification signal, INT is 1, indicating that the input notification signal is valid, INT is 0, indicating that the input notification signal is invalid, CS1 is 1, indicating that the error detection result of the first error detection code is an error, CS1 is 0, indicating that the error detection result of the first error detection code is not an error, CS2 is 1, indicating that the error detection result of the second error detection code is an error, CS2 is 0, indicating that the error detection result of the second error detection code is not an error, ESDD is 1, indicating that electrostatic discharge interference occurs, ESDD is 0, indicating that no electrostatic discharge interference occurs, INTP is 1, indicating that the output notification signal is valid, and INTP is 0, indicating that the output notification signal is invalid.

11. The vehicle touch circuit device according to claim 9, wherein: The ESD protector includes: A first logic OR gate having an output terminal and two input terminals respectively connected to the first error detection signal and the second error detection signal; a second logic OR gate having an output terminal and two input terminals respectively connected to the detection result signal and the output terminal of the first logic OR gate; a logic exclusive OR gate having an output terminal and two input terminals respectively connected to the input notification signal and the output terminal of the second logic OR gate; and A logic AND gate has two input terminals respectively connected to the input notification signal and the output terminal of the logic exclusive OR gate, and an output terminal for generating the output notification signal.

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