Key trigger circuit and electronic equipment

Abstract

The invention relates to the technical field of electronic circuits, and discloses a key trigger circuit and electronic equipment, and the circuit comprises a touch sensor and a conversion module; the conversion module is respectively connected with the main control module and the touch sensor; the touch sensor is used for transmitting a generated pressing signal to the conversion module when the touch sensor is pressed, and the pressing signal is a low-level signal; and the conversion module is used for converting the pressing signal into a digital signal when the falling edge of the pressing signal is detected, and transmitting the digital signal to the main control module, so that the main control module triggers a corresponding function according to the digital signal. Compared with an existing method that the main control module is mistakenly triggered due to high-level burrs caused by vibration sensing, the touch sensor can output a low-level pressing signal when being pressed, and the conversion module outputs a digital signal to the main control module to trigger a corresponding function when detecting a falling edge of the pressing signal, so that the mistakenly triggered of the main control module is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to a key trigger circuit and an electronic device. Background Art

[0002] At present, many multifunctional seats have exciters and other vibration devices embedded in the backrests, armrests, etc. These multifunctional seats also abandon the traditional combination of multiple mechanical buttons and switches for the overall beauty and integration of the seats, and use touch sensors (such as thin film pressure sensors) that are light, thin, and customizable.

[0003] When the touch sensor is pressed, the generated pressing signal can be transmitted to the main control module of the seat, where the analog-to-digital converter converts it into a digital signal, which is then recognized by the main control module and triggers the corresponding function. However, since multifunctional seats generally have a vibration function, in addition to the strong vibration in the vibration area, the vibration will also be transmitted to the touch sensor area. These vibrations may cause interference to the touch sensor circuit, generally in the form of high-level glitches, which in turn causes the subsequent main control module to trigger the corresponding function immediately after detecting the rising edge, resulting in false triggering. Summary of the invention

[0004] The main purpose of the present application is to provide a key trigger circuit and an electronic device, aiming to solve the existing technical problem that the circuit of the touch sensor is disturbed due to vibration, thereby causing false triggering of the main control module.

[0005] To achieve the above-mentioned purpose, the present application provides a key trigger circuit, the circuit comprising: a touch sensor and a conversion module;

[0006] The conversion module is connected to the main control module and the touch sensor respectively;

[0007] The touch sensor is used to transmit a generated pressing signal to the conversion module when pressed, and the pressing signal is a low-level signal;

[0008] The conversion module is used to convert the pressing signal into a digital signal when a falling edge of the pressing signal is detected, and transmit the digital signal to the main control module, so that the main control module triggers a corresponding function according to the digital signal.

[0009] In one embodiment, the conversion module includes: a discharge unit and a conversion unit;

[0010] The discharge unit is connected to the touch sensor and the conversion unit respectively, and the conversion unit is also connected to the main control module;

[0011] The discharge unit is used to discharge the pressing signal and transmit the discharged pressing signal to the conversion unit;

[0012] The conversion unit is used to convert the released pressure signal into a digital signal when a falling edge of the released pressure signal is detected, and transmit the digital signal to the main control module.

[0013] In one embodiment, the circuit further comprises: a voltage follower module;

[0014] The voltage follower module is connected to the touch sensor and the conversion module respectively;

[0015] The voltage following module is used to perform voltage following on the pressing signal and transmit the pressing signal after voltage following to the conversion module;

[0016] The conversion module is further used to convert the voltage-followed pressing signal into a digital signal when a falling edge of the voltage-followed pressing signal is detected, and transmit the digital signal to the main control module.

[0017] In one embodiment, the circuit further comprises: a filter gain module;

[0018] The filtering gain module is connected to the touch sensor and the conversion module respectively;

[0019] The filtering gain module is used to perform low-pass filtering on the pressing signal, and to gain the pressing signal after the low-pass filtering, and transmit the gained pressing signal to the conversion module;

[0020] The conversion module is further configured to convert the gained pressing signal into a digital signal when a falling edge of the gained pressing signal is detected, and transmit the digital signal to the main control module.

[0021] In one embodiment, the first end of the touch sensor is connected to the power supply and the conversion module respectively, and the second end of the touch sensor is grounded;

[0022] The touch sensor is also used to convert the power supply signal provided by the power supply into a pressing signal when being pressed, and transmit the pressing signal to the conversion module.

[0023] In one embodiment, the circuit further includes: a first voltage dividing module;

[0024] The first voltage dividing module is connected to the power source and the first end of the touch sensor respectively;

[0025] The first voltage dividing module is used to perform a voltage division on the power supply signal provided by the power source, and transmit the voltage-divided power supply signal to the touch sensor.

[0026] In one embodiment, the circuit further comprises: a filtering module;

[0027] The filtering module is respectively connected to the power source and the first end of the touch sensor;

[0028] The filtering module is used to filter the power supply signal provided by the power supply, and transmit the filtered power supply signal to the touch sensor.

[0029] In one embodiment, the circuit further includes: a second voltage dividing module;

[0030] The second voltage dividing module is connected to the power source and the first end of the touch sensor respectively;

[0031] The second voltage dividing module is used to perform secondary voltage division on the power supply signal output by the power supply, and transmit the secondary voltage divided power supply signal to the touch sensor.

[0032] In one embodiment, the conversion module is further used to convert the pressing signal into a digital signal with a preset pulse width when a falling edge of the pressing signal is detected;

[0033] The main control module is used to trigger a corresponding function according to the digital signal when it is detected that the preset pulse width of the digital signal reaches a preset trigger condition.

[0034] In addition, to achieve the above-mentioned purpose, the present application also provides an electronic device, which includes the key trigger circuit as described above.

[0035] The present application provides a key trigger circuit and an electronic device, the circuit comprising: a touch sensor and a conversion module; the conversion module is connected to a main control module and the touch sensor respectively; the touch sensor is used to transmit a generated pressing signal to the conversion module when being pressed, and the pressing signal is a low-level signal; the conversion module is used to convert the pressing signal into a digital signal when detecting a falling edge of the pressing signal, and transmit the digital signal to the main control module, so that the main control module triggers a corresponding function according to the digital signal.

[0036] Since the touch sensor in the present application can generate a low-level pressing signal when pressed, and transmit the pressing signal to the conversion module, the conversion module converts the pressing signal into a digital signal when detecting the falling edge of the pressing signal and transmits it to the main control module, so that the main control module triggers the corresponding function according to the digital signal. Compared with the high-level burrs caused by the existing vibration sensing that cause the main control module to be falsely triggered, the present application can make the touch sensor output a low-level pressing signal when pressed, and make the conversion module output a digital signal to the main control module to trigger the corresponding function when detecting the falling edge of the pressing signal, thereby reducing the false triggering of the main control module. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0038] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0039] Figure 1 This is a structural diagram of the first embodiment of the key trigger circuit of the present application;

[0040] Figure 2 It is the force-sensitivity characteristic-pressure characteristic curve of the thin film pressure sensor;

[0041] Figure 3 This is a circuit schematic diagram of the first embodiment of the key trigger circuit of the present application;

[0042] Figure 4 This is a logic configuration diagram of the conversion chip in the first embodiment of the key trigger circuit of this application;

[0043] Figure 5 This is a schematic diagram of the trigger characteristics of the conversion chip in the first embodiment of the key trigger circuit of this application;

[0044] Figure 6 This is a structural diagram of the second embodiment of the key trigger circuit of the present application;

[0045] Figure 7 This is a circuit schematic diagram of the second embodiment of the key trigger circuit of the present application;

[0046] Figure 8 This is a structural diagram of the third embodiment of the key trigger circuit of the present application;

[0047] Fig. 9 This is a circuit schematic diagram of the third embodiment of the key trigger circuit of the present application.

[0048] Description of Figure Numbers:

[0049] Label name Label name C1~C5 The first capacitor to the fifth capacitor U1~U4 The first chip to the fourth chip R1~R11 The first resistor to the eleventh resistor

[0050] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0051] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0052] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0053] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0054] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0055] Understandably, many multifunctional seats currently have exciters and other vibration devices embedded in the backrests, armrests, etc. These multifunctional seats also abandon the traditional combination of multiple mechanical key switches for the overall aesthetics and integration of the seats, and use touch sensors (such as film pressure sensors) that are thin, light, and customizable.

[0056] When the touch sensor is pressed, the generated pressing signal can be transmitted to the analog-to-digital converter in the main control module and converted into a digital signal, which is then recognized by the main control module and triggers the corresponding function. However, since multifunctional seats generally have a vibration function, in addition to the strong vibration in the vibration area, the vibration will also be transmitted to the touch sensor area. These vibrations may cause interference to the touch sensor circuit, generally in the form of high-level glitches, which in turn causes the subsequent main control module to immediately trigger the corresponding function upon detecting the rising edge, resulting in false triggering.

[0057] Therefore, in order to solve the above defects, this embodiment provides a key trigger circuit. The touch sensor in this embodiment can generate a low-level pressing signal when pressed, and transmit the pressing signal to the conversion module. When the conversion module detects the falling edge of the pressing signal, it converts the pressing signal into a digital signal and transmits it to the main control module, so that the main control module triggers the corresponding function according to the digital signal. Compared with the high-level burrs caused by the existing vibration sense that cause the main control module to be falsely triggered, this embodiment can make the touch sensor output a low-level pressing signal when pressed, and make the conversion module output a digital signal to the main control module to trigger the corresponding function when detecting the falling edge of the pressing signal, thereby reducing the false triggering of the main control module.

[0058] For ease of understanding, the following combination Figures 1 to 9 The key trigger circuit provided in the embodiment of the present application is specifically introduced.

[0059] Reference Figure 1 , Figure 1 This is a structural diagram of the first embodiment of the key trigger circuit of the present application, and the first embodiment of the key trigger circuit of the present application is proposed, such as Figure 1 As shown, in this embodiment, the key trigger circuit includes: a touch sensor and a conversion module;

[0060] The conversion module is connected to the main control module and the touch sensor respectively;

[0061] The touch sensor is used to transmit a generated pressing signal to the conversion module when pressed, and the pressing signal is a low-level signal;

[0062] The conversion module is used to convert the pressing signal into a digital signal when a falling edge of the pressing signal is detected, and transmit the digital signal to the main control module, so that the main control module triggers a corresponding function according to the digital signal.

[0063] It is understandable that the key trigger circuit provided in this embodiment can be a circuit for triggering any key, such as the above-mentioned touch sensor, and of course other keys. This embodiment uses the scenario of triggering the key function of the touch sensor on the multifunctional seat for illustration. The above-mentioned touch sensor can be any device that realizes touch control. This embodiment uses a thin film pressure sensor for illustration, but is not limited to this.

[0064] It should be understood that the main control module can be a module for triggering functions on a multifunctional seat, such as a microcontroller unit (MCU), etc., which can be set according to actual conditions. The conversion module can be a module that converts analog signals into digital signals. In the application of vibration seats, the thin-film pressure sensor realizes a digital logic key function similar to a physical key 0 or 1. Therefore, the present embodiment can convert the pressing signal in the form of an analog signal into a digital signal through the conversion module.

[0065] It should also be understood that reference Figure 2 , Figure 2 It is the force-sensitive characteristic-pressure characteristic curve of the thin film pressure sensor, such as Figure 2 As shown, when the user does not press (i.e. Figure 2 When the pressure value is low (medium pressure value / Kgf), the first end of the thin film pressure sensor and the second end of the thin film pressure sensor are in a high resistance state (i.e. Figure 2 Medium resistance value / KΩ is higher), when the user presses (i.e. Figure 2 When the pressure value is high (Kgf), the first end of the thin film pressure sensor and the second end of the thin film pressure sensor are in a low resistance state (i.e. Figure 2 Medium resistance value / KΩ is lower);

[0066] The existing touch sensor is generally connected to a power supply at one end and to a main control module and a pair of ground resistors at the other end. When not pressed, the high-resistance state keeps it at a low level and the main control module is not triggered. When pressed, the low-resistance state causes it to output a high level, thereby generating a high-level pressing signal and transmitting it to the main control module, so that the main control module can immediately trigger the corresponding function when detecting the rising edge of the pressing signal. Since the interference caused by the vibration is also a high-level glitch, when the touch sensor is interfered by the vibration, a high-level pressing signal will also be generated, thereby causing the main control module to be falsely triggered.

[0067] The above-mentioned press signal in this embodiment is a low-level signal. In actual use, when the user presses the touch sensor, the touch sensor can generate a low-level press signal and transmit it to the conversion module. The conversion module determines whether the falling edge of the press signal is detected; if detected, it can be said that the user presses at this time, and then the press signal can be converted into a digital signal and transmitted to the main control module. The main control module can determine the corresponding function according to the digital signal to trigger it.

[0068] It should be emphasized that when the touch sensor is disturbed by vibration but the user does not press the touch sensor, a high-level glitch will be generated and transmitted to the conversion module. However, the conversion module does not detect the falling edge at this time, and thus will not generate a digital signal to transmit to the main control module. The main control module will not trigger the corresponding function, thereby reducing the false triggering phenomenon.

[0069] It should also be emphasized that when the touch sensor is disturbed by vibration but the user presses the touch sensor, since the touch sensor is pressed at this time, a low-level pressing signal can be generated and transmitted to the conversion module. The conversion module can detect the falling edge of the pressing signal and also trigger the main control module normally.

[0070] Furthermore, the existing touch sensor generally outputs a high-level pressing signal when pressed. In order to realize that the touch sensor in this embodiment outputs a low-level pressing signal when pressed, refer to Figure 3 , Figure 3 This is a circuit diagram of the first embodiment of the key trigger circuit of the present application, as shown in FIG. Figure 3 As shown, in this embodiment, the first end of the touch sensor is connected to the power supply and the conversion module respectively, and the second end of the touch sensor is grounded;

[0071] The touch sensor is also used to convert the power supply signal provided by the power supply into a pressing signal when being pressed, and transmit the pressing signal to the conversion module.

[0072] It is understandable that the power supply can be any power supply for operating the touch sensor, and this embodiment does not limit this. The power supply signal can be a signal provided by the power supply for operating the touch sensor. Since the film pressure sensor generally requires 3-5V DC, the power supply signal can be a DC signal of the corresponding voltage.

[0073] It should be understood that the first end of the touch sensor may be the first pin of the touch sensor, and the second end of the touch sensor may be the second pin of the touch sensor. Since in this embodiment, only one pin of the touch sensor needs to be connected to the power supply and the other pin is grounded, as another implementation, the first end of the touch sensor may also be the second pin of the touch sensor, and the second end of the touch sensor may also be the first pin of the touch sensor, and this embodiment does not limit this.

[0074] Furthermore, Figure 3 As shown, since the first end of the touch sensor is connected to the power supply and the conversion module, and the second end of the touch sensor is grounded, when the user does not press the touch sensor and the seat does not vibrate, the first end of the touch sensor and the second end of the touch sensor maintain a high impedance state, the first end of the touch sensor can maintain a high level, and the conversion module will not detect the falling edge, and no digital signal is generated and transmitted to the main control module, and the main control module is not triggered; when the user does not press the touch sensor, but the seat vibrates, the first end of the touch sensor and the second end of the touch sensor maintain a high impedance state, and the output of the first end of the touch sensor is also a high-level burr, and the conversion module still has no digital signal transmitted to the main control module, and the main control module is not triggered;

[0075] When the user presses the touch sensor, if the seat does not vibrate, the first end of the touch sensor and the second end of the touch sensor become low-resistance state and are turned on, and the first end of the touch sensor outputs a low-level pressing signal. The conversion module can detect the falling edge of the pressing signal and transmit the obtained digital signal to the main control module, and the main control module triggers the corresponding function normally; when the user presses the touch sensor, but the seat vibrates, the first end of the touch sensor and the second end of the touch sensor are low-resistance state and are turned on, and there will be no high-level burrs at the first end of the touch sensor, but a low-level pressing signal is output. The conversion module can detect the falling edge of the pressing signal and transmit the obtained digital signal to the main control module, and the main control module triggers the corresponding function normally.

[0076] Furthermore, in order to improve the response speed, continue as follows Figure 1 As shown, in this embodiment, the conversion module includes: a discharge unit and a conversion unit;

[0077] The discharge unit is connected to the touch sensor and the conversion unit respectively, and the conversion unit is also connected to the main control module;

[0078] The discharge unit is used to discharge the pressing signal and transmit the discharged pressing signal to the conversion unit;

[0079] The conversion unit is used to convert the released pressure signal into a digital signal when a falling edge of the released pressure signal is detected, and transmit the digital signal to the main control module.

[0080] It should be noted that the above-mentioned discharge unit can be a unit for realizing rapid discharge of charge. In this embodiment, when the touch sensor does not output a pressing signal, the discharge unit does not output a pressing signal after discharge, the conversion unit does not output a digital signal, and the main control module does not trigger; when the touch sensor outputs a pressing signal, the discharge unit can quickly discharge the charge of the pressing signal, and transmit the discharged pressing signal to the conversion unit to ensure a rapid response of the input interface of the conversion unit, and the conversion unit then detects the falling edge of the discharged pressing signal, generates a digital signal and transmits it to the main control module, and the main control module triggers the corresponding function normally.

[0081] Further, continue as Figure 3 As shown, in this embodiment, the discharge unit includes: a first resistor R1 and a first capacitor C1;

[0082] The first end of the first resistor R1 is connected to the first end of the touch sensor and the first end of the first capacitor C1 respectively, and the second end of the first resistor R1 is connected to the second end of the first capacitor C1 and the conversion unit respectively.

[0083] In actual use, the first end of the touch sensor outputs a pressing signal to the discharge unit, and the first resistor R1 limits the large current input to the conversion unit, thereby protecting the conversion unit. The first capacitor C1 is connected in parallel with the first resistor R1, and when a low-level pressing signal is received, the charge on one end of the conversion unit connected to the second end of the first resistor R1 is quickly discharged, thereby ensuring that the conversion unit quickly responds to the low-level pressing signal.

[0084] Further, continue as Figure 3 As shown, in this embodiment, the conversion unit includes: a first chip U1, a second resistor R2, a second capacitor C2 and a third capacitor C3;

[0085] The clear terminal of the first chip U1 (i.e., the first pin of the first chip U1) is connected to the first input terminal of the first chip U1 (i.e., the second pin of the first chip U1), the second input terminal of the first chip U1 (i.e., the third pin of the first chip U1) is connected to the second end of the first resistor R1, the ground terminal of the first chip U1 (i.e., the fourth pin of the first chip U1) is grounded, and the power terminal of the first chip U1 (i.e., the fifth pin of the first chip U1) is respectively connected to the clear terminal of the first chip U1, the second end of the second resistor R2, the first end of the third capacitor C3, and the power supply (i.e., Figure 3 The first chip U1 is connected to VDD, the second end of the third capacitor C3 is grounded, the first adjustment end of the first chip U1 (that is, the sixth pin of the first chip U1) is respectively connected to the first end of the second resistor R2 and the second end of the second capacitor C2, the second adjustment end of the first chip U1 (that is, the seventh pin of the first chip U1) is connected to the first end of the second capacitor C2, and the output end of the first chip U1 (that is, the eighth pin of the first chip U1) is connected to the main control module.

[0086] It is understandable that the first chip U1 can be any chip that generates a digital signal when a falling edge is detected. This embodiment uses a Schmitt trigger as the first chip U1 for illustration. That is, after the first resistor R1 transmits the released pressing signal to the second input terminal of the Schmitt trigger, the Schmitt trigger can perform analog-to-digital conversion when its falling edge is detected, and transmit the generated digital signal to the main control module through the output terminal of the Schmitt trigger.

[0087] In order to make the Schmitt trigger realize falling edge trigger, Figure 3 As shown, in this embodiment, the first pin of the first chip U1 and the second pin of the first chip U1 can be connected to the power supply and set high, and then the output can follow the input of the third pin of the first chip U1 to achieve the level pulse falling edge trigger function, refer to Figure 4 , Figure 4 This is a logic configuration diagram of the first chip U1 in the first embodiment of the key trigger circuit of this application, such as Figure 4As shown, the first pin of the first chip U1 and the second pin of the first chip U1 are connected to the power supply, and then the first pin of the first chip U1 (ie Figure 4 CLR is high (i.e. Figure 4 H), the second pin of the first chip U1 (ie Figure 4 B) is also high level (i.e. Figure 4 H), the third pin of the first chip U1 (ie Figure 4 A) is a falling edge trigger (i.e. Figure 4 ↓), the eighth pin of the first chip U1 (i.e. Figure 4 OUT) outputs digital signal (i.e. Figure 4 middle ).

[0088] Reference Figure 5 , Figure 5 Schematic diagram of trigger characteristics of the first chip U1 in the first embodiment of the key trigger circuit of this application, as shown in FIG. Figure 5 As shown, the first pin of the first chip U1 and the second pin of the first chip U1 are connected to the power supply, and then the first pin of the first chip U1 (ie Figure 5 CLR) and the second pin of the first chip U1 (i.e. Figure 5 Middle B) is high level;

[0089] When the seat is not vibrating, the user presses the trigger (i.e. Figure 5 When the normal key recognition pulse is triggered, the trigger outputs a low-level pressing signal which is transmitted to the first chip U1 through the first resistor R1. The third pin (i.e. Figure 5 A) receives the low-level pressing signal, and since it is a low level, it has a falling edge (i.e. Figure 5 ↓), after detecting the falling edge of the pressing signal, the first chip U1 can convert it into a high-level digital signal and transmit it through the eighth pin (i.e. Figure 5 OUT) is output to the main control module, so that the main control module triggers the corresponding function;

[0090] When the seat vibrates, the user does not press the trigger (i.e. Figure 5 When the interference in ③ cannot trigger the button), the trigger can output a high-level glitch to the third pin of the first chip U1 (i.e. Figure 5 There is a fluctuation in A), the eighth pin of the first chip U1 has no digital signal output, and the main control chip is not triggered;

[0091] When the seat vibrates, the user presses the trigger (i.e. Figure 5 ② When the key is pressed, the trigger can output high-level glitch (i.e. Figure 5A fluctuates in the middle) and becomes a low-level pressing signal (i.e. Figure 5 ↓), after detecting the falling edge of the pressing signal, the first chip U1 can convert it into a high-level digital signal and transmit it through the eighth pin (i.e. Figure 5 OUT) is output to the main control module, so that the main control module triggers the corresponding function.

[0092] Furthermore, in order to further reduce the probability of false triggering, in this embodiment, the conversion module is also used to convert the pressing signal into a digital signal with a preset pulse width when a falling edge of the pressing signal is detected;

[0093] The main control module is used to trigger a corresponding function according to the digital signal when it is detected that the preset pulse width of the digital signal reaches a preset trigger condition.

[0094] It should be understood that the conversion module in this embodiment can generate a digital signal with a preset pulse width when generating a digital signal. For the convenience of subsequent description, the preset pulse width is recorded as t w The above-mentioned preset trigger condition can be a condition for detecting whether the pulse width of the digital signal meets the trigger requirement. In this embodiment, the preset trigger condition can be set to whether the pulse width of the digital signal is t w .

[0095] Then in actual use, continue as Figure 5 As shown, when the conversion module detects the falling edge of the pressing signal, the pressing signal can be converted into a pulse width of t w The digital signal (i.e. Figure 5 Medium w ) and transmit it to the main control module; after receiving the digital signal, the main control module can determine whether its pulse width is t w , if t w , it can be explained as a valid digital signal, thereby triggering the corresponding function. If it is not t w , it can be explained as other interference and judged as an invalid key, and then not triggered, further reducing false trigger recognition.

[0096] Further, continue as Figure 3 As shown, in this embodiment, the resistance value of the second resistor R2 and the capacitance value of the second capacitor C2 can be set to adjust t w , where t w The calculation formula can be as follows:

[0097] t w =K×R 2 ×C 2 Formula 1;

[0098] K is a coefficient constant, usually 0.85, R2 is the resistance of the second resistor R2, C 2 is the capacitance of the second capacitor C2. According to the actual simulated user key test, you can choose a suitable R 2 and C 2 , thus setting t w In this embodiment, according to the common key operation habits, t w The value is between 0.5ms and 10ms. In this embodiment, the specific value t w =1ms.

[0099] It should be emphasized that when the seat shakes, even if the third pin of the first chip U1 receives a downward fluctuation (i.e. Figure 5 However, since the fluctuation does not reach the voltage value when there is a falling edge, for the first chip U1, the downward fluctuation is not a falling edge, and thus no triggering occurs.

[0100] The touch sensor in this embodiment can generate a low-level pressing signal when pressed, and transmit the pressing signal to the conversion module. When the conversion module detects the falling edge of the pressing signal, it converts the pressing signal into a digital signal and transmits it to the main control module, so that the main control module triggers the corresponding function according to the digital signal. Compared with the high-level burrs caused by the existing vibration sensing that cause the main control module to be falsely triggered, this embodiment can make the touch sensor output a low-level pressing signal when pressed, and make the conversion module output a digital signal to the main control module to trigger the corresponding function when detecting the falling edge of the pressing signal, thereby reducing false triggering of the main control module.

[0101] At the same time, since the conversion module in this embodiment can convert the pressing signal in the form of an analog signal into a digital signal, digital filtering of the signal is realized, and the digital signal output by the first chip U1 is set to a preset pulse width. The main control module detects whether the pulse width of the received digital signal reaches the preset pulse width, thereby further reducing the probability of false triggering of the button.

[0102] Reference Figure 6 , Figure 6 This is a structural diagram of the second embodiment of the key trigger circuit of the present application. Based on the above-mentioned first embodiment, the second embodiment of the key trigger circuit of the present application is proposed.

[0103] In order to improve the input impedance of the subsequent circuit and reduce the impact on the subsequent circuit, such as Figure 6 As shown, in this embodiment, the above circuit further includes: a voltage follower module;

[0104] The voltage follower module is connected to the touch sensor and the conversion module respectively;

[0105] The voltage following module is used to perform voltage following on the pressing signal and transmit the pressing signal after voltage following to the conversion module;

[0106] The conversion module is further used to convert the voltage-followed pressing signal into a digital signal when a falling edge of the voltage-followed pressing signal is detected, and transmit the digital signal to the main control module.

[0107] It should be noted that the voltage following module can be any module that implements voltage following, such as a voltage follower, etc., and this embodiment does not limit this. Specifically, the voltage following module can be connected to the first end of the touch sensor and the discharge unit in the conversion module.

[0108] In actual use, when the touch sensor outputs a press signal, the voltage following module can perform voltage follow on the press signal, and transmit the press signal after voltage following to the discharge unit for discharge. The discharge unit then transmits the released press signal to the conversion unit. When the conversion unit detects the falling edge of the released press signal, it converts the released press signal into a digital signal and transmits the digital signal to the main control module.

[0109] Further, refer to Figure 7 , Figure 7 This is a circuit diagram of the second embodiment of the key trigger circuit of the present application, as shown in FIG. Figure 7 As shown, in this embodiment, the voltage follower module includes: a second chip U2 and a fourth resistor R4;

[0110] The inverting input terminal of the second chip U2 (i.e. Figure 7 The first pin of the second chip U2 in the circuit is connected to the first end of the fourth resistor R4, and the positive input end of the second chip U2 (i.e. Figure 7 The second pin of the second chip U2 in the circuit) is connected to the first end of the touch sensor, and the output end of the second chip U2 (i.e. Figure 7 The third pin of the second chip U2 is connected to the first end of the first resistor R1.

[0111] It should be noted that the second chip U2 may be a chip with a voltage follower function. In this embodiment, an emitter follower may be used. Of course, it may also be other chips with the same function, and this embodiment does not limit this.

[0112] In actual use, the positive input end of the second chip U2 can receive the pressing signal output by the touch sensor, and perform voltage following on it, and then transmit the pressing signal after voltage following to the first resistor R1 through the output end of the second chip U2, thereby reducing the impact on the subsequent circuit.

[0113] Furthermore, considering that the operating frequency range of the exciter of the vibration seat is generally within 200Hz, the vibration of the exciter will derive higher frequency harmonic vibrations through the entire system structure of the seat. Therefore, in order to reduce the interference caused by it, continue as follows Figure 6 As shown, in this embodiment, the above circuit further includes: a filter gain module;

[0114] The filtering gain module is connected to the touch sensor and the conversion module respectively;

[0115] The filtering gain module is used to perform low-pass filtering on the pressing signal, and to gain the pressing signal after the low-pass filtering, and transmit the gained pressing signal to the conversion module;

[0116] The conversion module is further used to convert the gained pressing signal into a digital signal when a falling edge of the gained pressing signal is detected, and transmit the digital signal to the main control module.

[0117] It is understandable that the filter gain module in this embodiment can be a module that implements low-pass filtering and gain functions. The filter gain module in this embodiment can be connected to the voltage follower module and the discharge unit in the conversion module respectively.

[0118] In actual use, after the voltage follower module outputs the pressing signal after voltage following to the filter gain module, the filter gain module can perform a low-pass filter on the pressing signal after voltage following, filter out the high-frequency harmonic vibration, and then perform a gain, and then transmit the gained pressing signal to the discharge unit for discharge.

[0119] Further, continue to refer to Figure 7 In this embodiment, the filtering gain module includes: a third chip U3, a fifth resistor R5 to an eighth resistor R8, a fourth capacitor C4 and a fifth capacitor C5;

[0120] The first end of the fifth resistor R5 is connected to the output end of the second chip U2, the second end of the fifth resistor R5 is respectively connected to the first end of the fifth capacitor C5 and the first end of the sixth resistor R6, the second end of the sixth resistor R6 is respectively connected to the first end of the fourth capacitor C4 and the reverse input end of the third chip U3 (i.e. Figure 7 The second end of the fourth capacitor C4 is grounded, and the second end of the fifth capacitor C5 is connected to the output end of the third chip U3 (i.e. Figure 7 The third pin of the third chip U3 is connected to the first end of the seventh resistor R7 and the first end of the first resistor R1, and the second end of the seventh resistor R7 is connected to the positive input end of the third chip U3 (ie Figure 7A second pin of the third chip U3 is connected to a first end of an eighth resistor R8, and a second end of the eighth resistor R8 is grounded.

[0121] It should be understood that the third chip U3 may be any chip that implements low-pass filtering and gain, such as an active low-pass filter, etc., and this embodiment does not limit this.

[0122] It should also be understood that in this embodiment, the low-pass cutoff frequency of the filter gain module can be set by setting the resistance of the fifth resistor R5, the resistance of the sixth resistor R6, the capacitance of the fourth capacitor C4 and the capacitance of the fifth capacitor C5. 1 The low-pass cutoff frequency f can be set by the following formula 2 1 ,Right now:

[0123]

[0124] Where R 5 is the resistance value of the fifth resistor R5, R 6 is the resistance value of the sixth resistor R6, C 4 is the capacitance of the fourth capacitor C4, C 5 is the capacitance of the fifth capacitor C5, which can be set according to actual conditions, and is not limited in this embodiment.

[0125] At the same time, in this embodiment, the gain multiple can be adjusted by setting the resistance value of the seventh resistor R7 and the resistance value of the eighth resistor R8. If the gain is recorded as G 1 The gain G can be set by the following formula 3 1 ,Right now:

[0126]

[0127] Where R 7 is the resistance value of the seventh resistor R7, R 8 is the resistance value of the eighth resistor R8, and the stability of the filter needs to be considered to prevent self-oscillation.

[0128] In addition, the quality factor (ie, Q value) of the third chip U3 should not be too high, usually Q=0.707 or so. The calculation formula of the Q value in this embodiment is shown in the following formula 4, that is:

[0129]

[0130] Then, according to the low-pass cutoff frequency f 1 , gain G 1 And Q value requirements, select appropriate resistance values ​​of the fifth resistor R5, the sixth resistor R6, the fourth capacitor C4 and the fifth capacitor C5 to meet the design requirements.

[0131] Reference Figure 8 , Figure 8 This is a structural schematic diagram of the third embodiment of the key trigger circuit of the present application. Based on the above embodiments, the third embodiment of the key trigger circuit of the present application is proposed.

[0132] Considering that the voltage of the power supply signal received by the touch sensor may be relatively high, in this embodiment, the circuit further includes: a first voltage dividing module;

[0133] The first voltage dividing module is connected to the power source and the first end of the touch sensor respectively;

[0134] The first voltage dividing module is used to perform a voltage division on the power supply signal provided by the power source, and transmit the voltage-divided power supply signal to the touch sensor.

[0135] It is understandable that the first voltage division module may be any module for voltage division, such as a resistor, etc., and this embodiment does not limit this.

[0136] In actual use, the power supply can transmit the power signal to the first voltage divider module, and the first voltage divider module can divide the power signal. For the convenience of subsequent description, this embodiment is recorded as one voltage division, and the power signal after the one voltage division is transmitted to the first end of the touch sensor. When the touch sensor is pressed, the power signal after the one voltage division can be converted into a pressing signal.

[0137] Furthermore, in order to provide the touch sensor with a stable power supply voltage with sufficient driving capability, such as Figure 8 As shown, in this embodiment, the circuit further includes: a filtering module;

[0138] The filtering module is respectively connected to the power source and the first end of the touch sensor;

[0139] The filtering module is used to filter the power supply signal provided by the power supply, and transmit the filtered power supply signal to the touch sensor.

[0140] It should be noted that the above-mentioned filtering module may be a module with filtering function, such as a follower, etc., and this embodiment does not limit this.

[0141] In actual use, the power supply can transmit the power supply signal to the filter module, which can filter it and transmit the filtered power supply signal to the touch sensor, so that when the touch sensor is pressed, the filtered power supply signal is converted into a pressing signal. When the above-mentioned first voltage divider module is provided, the above-mentioned filter module can be connected to the first voltage divider module, transmit the filtered power supply signal to the first voltage divider module for one voltage division, and then transmit the power supply signal after one voltage division to the touch sensor.

[0142] Further, in order to broaden the voltage range of the power supply signal received by the filter module, continue as follows Figure 8 As shown, in this embodiment, the circuit further includes: a second voltage dividing module;

[0143] The second voltage dividing module is connected to the power source and the first end of the touch sensor respectively;

[0144] The second voltage dividing module is used to perform secondary voltage division on the power supply signal output by the power supply, and transmit the secondary voltage divided power supply signal to the touch sensor.

[0145] It is understandable that the second voltage division module may be any module that performs voltage division, such as a resistor.

[0146] In actual use, the power supply signal output by the power supply can be first transmitted to the second voltage divider module for voltage division. For the convenience of subsequent description, this embodiment is recorded as secondary voltage division. The second voltage divider module can transmit the secondary voltage-divided power supply signal to the first end of the touch sensor, and when the touch sensor is pressed, the secondary voltage-divided power supply signal can be converted into a pressing signal. Similarly, when a filtering module is provided, the second voltage divider module can be connected to the filtering module, and then the second voltage divider module transmits the secondary voltage-divided power supply signal to the filtering module for filtering, and then transmits the filtered power supply signal to the first end of the touch sensor.

[0147] Since the present embodiment can perform secondary voltage division on the power supply signal through the second voltage division module, the voltage range of the power supply provided by the power supply can be widened.

[0148] Further, refer to Fig. 9 , Fig. 9 This is a circuit diagram of the third embodiment of the key trigger circuit of the present application, as shown in FIG. Fig. 9 As shown, in this embodiment, the first voltage dividing module includes: a third resistor R3;

[0149] A first end of the third resistor R3 is connected to a power source (i.e. Fig. 9 The second end of the third resistor R3 is connected to the first end of the touch sensor.

[0150] It should be understood that the resistance value of the third resistor R3 may be in the range of 1K to 100KΩ, and may be set according to actual conditions, which is not limited in this embodiment.

[0151] In actual use, the third resistor R3 can divide the power supply signal provided by the power supply and transmit the divided signal to the first end of the touch sensor.

[0152] Further, continue as Fig. 9 As shown, the second voltage dividing module includes: a ninth resistor R9 and a tenth resistor R10;

[0153] The first end of the ninth resistor R9 is connected to the power supply (ie Fig. 9 The second end of the ninth resistor R9 is connected to the filtering module and the first end of the tenth resistor R10 respectively, and the second end of the tenth resistor R10 is grounded.

[0154] It should be understood that the resistance value of the ninth resistor R9 and the resistance value of the tenth resistor R10 can be set according to actual conditions.

[0155] In actual use, after the power supply signal provided by the power source is transmitted to the second voltage divider module, the ninth resistor R9 and the tenth resistor R10 can divide the power supply voltage and transmit the divided power supply signal to the filter module.

[0156] Further, continue as Fig. 9 As shown, in this embodiment, the filtering module includes: a fourth chip U4 and an eleventh resistor R11;

[0157] The reverse input terminal of the fourth chip U4 (ie Fig. 9 The first pin of the fourth chip U4 is connected to the first end of the eleventh resistor R11, and the positive input terminal of the fourth chip U4 (i.e. Fig. 9 The second pin of the fourth chip U4 is connected to the second end of the ninth resistor R9, and the output end of the fourth chip U4 (i.e. Fig. 9 The third pin of the fourth chip U4 is respectively connected to the second end of the eleventh resistor R11 and the first end of the third resistor R3.

[0158] It should be noted that the fourth chip U4 may be a chip with a filtering function, and this embodiment uses an emitter follower for illustration.

[0159] In actual use, the positive input end of the fourth chip U4 can receive the divided power supply signal, filter the divided power supply signal, and then transmit the filtered power supply signal to the third resistor R3 through the output end of the fourth chip U4 for voltage division.

[0160] At the same time, through the above connection method, the fourth chip U4 can also form a voltage follower function, that is, it performs voltage following on the divided power supply signal, and then transmits the filtered and voltage-followed power supply signal to the touch sensor, further improving the stability of the touch sensor power supply.

[0161] In addition, to achieve the above-mentioned purpose, an embodiment of the present application further provides an electronic device, which includes the key trigger circuit as described above.

[0162] Other embodiments or specific implementation methods of the electronic device of the present application can refer to the embodiments of the above-mentioned key trigger circuits, which will not be repeated here.

[0163] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A key trigger circuit, characterized in that: The circuit includes: a touch sensor and a conversion module; The conversion module is connected to the main control module and the touch sensor respectively; The touch sensor is used to transmit a generated pressing signal to the conversion module when pressed, and the pressing signal is a low-level signal; The conversion module is used to convert the pressing signal into a digital signal when a falling edge of the pressing signal is detected, and transmit the digital signal to the main control module, so that the main control module triggers a corresponding function according to the digital signal.

2. The key trigger circuit according to claim 1, characterized in that: The conversion module includes: a discharge unit and a conversion unit; The discharge unit is connected to the touch sensor and the conversion unit respectively, and the conversion unit is also connected to the main control module; The discharge unit is used to discharge the pressing signal and transmit the discharged pressing signal to the conversion unit; The conversion unit is used to convert the released pressure signal into a digital signal when a falling edge of the released pressure signal is detected, and transmit the digital signal to the main control module.

3. The key trigger circuit according to claim 1, characterized in that: The circuit further comprises: a voltage follower module; The voltage follower module is connected to the touch sensor and the conversion module respectively; The voltage following module is used to perform voltage following on the pressing signal and transmit the pressing signal after voltage following to the conversion module; The conversion module is further used to convert the voltage-followed pressing signal into a digital signal when a falling edge of the voltage-followed pressing signal is detected, and transmit the digital signal to the main control module.

4. The key trigger circuit according to claim 1, characterized in that: The circuit further comprises: a filter gain module; The filtering gain module is connected to the touch sensor and the conversion module respectively; The filtering gain module is used to perform low-pass filtering on the pressing signal, and to gain the pressing signal after the low-pass filtering, and transmit the gained pressing signal to the conversion module; The conversion module is further used to convert the gained pressing signal into a digital signal when a falling edge of the gained pressing signal is detected, and transmit the digital signal to the main control module.

5. The key trigger circuit according to claim 1, characterized in that: The first end of the touch sensor is connected to the power supply and the conversion module respectively, and the second end of the touch sensor is grounded; The touch sensor is also used to convert the power supply signal provided by the power supply into a pressing signal when being pressed, and transmit the pressing signal to the conversion module.

6. The key trigger circuit as claimed in claim 5, characterized in that: The circuit further includes: a first voltage dividing module; The first voltage dividing module is connected to the power source and the first end of the touch sensor respectively; The first voltage dividing module is used to perform a voltage division on the power supply signal provided by the power source, and transmit the voltage-divided power supply signal to the touch sensor.

7. The key trigger circuit as claimed in claim 5, characterized in that: The circuit further comprises: a filtering module; The filtering module is respectively connected to the power source and the first end of the touch sensor; The filtering module is used to filter the power supply signal provided by the power supply, and transmit the filtered power supply signal to the touch sensor.

8. The key trigger circuit as claimed in claim 5, characterized in that: The circuit further includes: a second voltage dividing module; The second voltage dividing module is connected to the power source and the first end of the touch sensor respectively; The second voltage dividing module is used to perform secondary voltage division on the power supply signal output by the power supply, and transmit the secondary voltage divided power supply signal to the touch sensor.

9. The key trigger circuit according to any one of claims 1 to 8, characterized in that: The conversion module is further configured to convert the pressing signal into a digital signal of a preset pulse width when a falling edge of the pressing signal is detected; The main control module is used to trigger a corresponding function according to the digital signal when it is detected that the preset pulse width of the digital signal reaches a preset trigger condition.

10. An electronic device, characterized in that: The electronic device comprises the key trigger circuit according to any one of claims 1 to 9.

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