Mutual capacitance type touch product triggering device and method and electronic touch equipment

Abstract

The invention discloses a mutual capacitance type touch product triggering device and method and electronic touch equipment, and is applied to the technical field of mutual capacitance type touch. The force sensor and the mutual capacitance detection module are used for cooperatively detecting the touch signal applied to the touch product, and the Shiled electrode provides the potential equal to the Tx electrode in potential, so that water drops falling on the touch surface of the touch product have the potential equal to the environment; the influence on mutual capacitance between the Tx electrode and the Rx electrode when water drops only contact the Tx electrode or the Rx electrode is shielded; and meanwhile, the force sensor can detect the pressure when a finger touches the touch surface of the touch product. Therefore, the touch function arousing when the water drops drop to touch the product is reasonably avoided, and the problem of mistaken touch caused by the fact that conductors such as the water drops make contact with mutual capacitance products is solved.

Description

Technical Field

[0001] The present invention relates to the field of mutual-capacitive touch technology, and in particular to a mutual-capacitive touch product triggering device, method and electronic touch equipment. Background Art

[0002] Mutual capacitance touch technology is a technology based on the principle of capacitive sensing and is widely used in electronic touch devices. In a mutual capacitance touch system, there are transmitting electrodes and receiving electrodes. When a conductive object such as a finger approaches the touch panel, it changes the mutual capacitance between the electrodes. The touch controller determines the touch position by detecting these changes in capacitance. Figure 1 As shown in the figure, the Tx electrode is the transmitting electrode and the Rx electrode is the receiving electrode. When the finger touches the Rx electrode and the Tx electrode, Figure 2 As shown in Figure 2, the mutual capacitance between the Rx electrode and the Tx electrode decreases. When the water droplet contacts the Rx electrode and the Tx electrode, as shown in Figure 2, the mutual capacitance between the Rx electrode and the Tx electrode decreases. Figure 3 As shown, an inductive capacitance Cf is generated between the water droplets and the Rx electrode and the Tx electrode, which is equivalent to two inductive capacitances connected in series and in parallel with the original Cm capacitance, which is equivalent to the water droplets increasing the mutual capacitance between the Rx electrode and the Tx electrode.

[0003] If the water droplets stay for a while and then are removed, the equivalent mutual capacitance between the Rx electrode and the Tx electrode becomes smaller, similar to the reduction in mutual capacitance caused by a finger touch, thus causing false touches.

[0004] It can be seen that how to solve the false touch caused by conductors such as water droplets contacting mutual capacitance products is a technical problem that needs to be solved urgently by people in this field. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a mutual-capacitance touch product triggering device, method and electronic touch device, which solves the problem of false touch caused by conductors such as water droplets contacting mutual-capacitance products. The specific scheme is as follows:

[0006] In a first aspect, the present application provides a mutual capacitance touch product trigger device, including: a force sensor, a mutual capacitance detection module and a microcontroller unit (MCU);

[0007] The mutual capacitance detection module comprises: a group of Tx electrodes, Rx electrodes and Shiled electrodes, wherein the Tx electrodes, the Rx electrodes, the Shiled electrodes and the force sensor are all arranged between the electrode attachment and support materials and the covering protective layer;

[0008] The Shiled electrode surrounds the Tx electrode and the Rx electrode and is used to provide a potential equal to that of the Tx electrode;

[0009] The Tx electrode is used to transmit an electrical signal, and the Rx electrode is used to receive an electrical signal, and the two electrodes are coupled to form mutual capacitance;

[0010] The MCU is connected to the Tx electrode, the Rx electrode, the Shiled electrode and the force sensor, and is used to provide an equipotential voltage source for the Tx electrode and the Shiled electrode, and receive a first signal representing the pressure on the force sensor and a second signal representing the equivalent mutual capacitance between the Tx electrode and the Rx electrode, and then determine whether to trigger the touch function based on the first signal and the second signal.

[0011] Optionally, the force sensor is arranged below the mutual capacitance detection module.

[0012] Optionally, there are multiple mutual capacitance detection modules, and the multiple mutual capacitance detection modules are connected to the same MCU.

[0013] Optionally, the Tx electrode, the Rx electrode and the Shiled electrode are connected to a signal end that sends a fixed sequence charge and discharge signal.

[0014] In a second aspect, the present application provides a method for triggering a mutual-capacitance touch product, including:

[0015] Acquire a first signal representing a pressure change of the force sensor and a second signal representing a capacitance change detected by a mutual capacitance detection module;

[0016] Whether a touch function is triggered is determined according to the first signal and the second signal.

[0017] Optionally, determining whether to trigger a touch function according to the first signal and the second signal includes:

[0018] detecting the first signal transmitted by the force sensor;

[0019] If the first signal meets a first condition, the second signal transmitted by the mutual capacitance detection module is detected, and the first condition is: the pressure increase of the force sensor reflected by the first signal is greater than a first threshold value;

[0020] If the second signal meets the second condition, the touch product function is triggered, and the second condition is that the capacitance value detected by the mutual capacitance detection module reflected by the second signal is greater than the first baseline and the difference between the two is greater than a threshold value, and the threshold value is a sensitivity-related variable;

[0021] If the first signal does not satisfy the first condition or the second signal does not satisfy the second condition, it is determined that the current touch operation is an incorrect touch operation.

[0022] Optionally, obtaining a second signal representing a capacitance change detected by the mutual capacitance detection module includes:

[0023] Discharging the mutual capacitance and the measurement capacitance of the Tx electrode and the Rx electrode until the charge amounts of the mutual capacitance and the measurement capacitance are zero;

[0024] Setting the Tx electrode to a high potential and the Rx electrode to a low potential, so that the mutual inductance capacitor short-circuits the Tx electrode and the Rx electrode, and charges the mutual inductance capacitor;

[0025] The Tx electrode and the Rx electrode disconnect the input of the electrical signal, so that the mutual capacitance shorts the measuring capacitance to transfer all the charges to the measuring capacitance until the measuring capacitance voltage is greater than the reference voltage. If the measuring capacitance voltage is less than the reference voltage, the mutual capacitance charging step is returned;

[0026] The mutual capacitance charging times are counted, and the mutual capacitance charging times are recorded as the second signal.

[0027] Optionally, the first baseline is a time-related variable;

[0028] When the duration of the second signal exceeds a time threshold, the first baseline changes asymptotically, gradually approaching the value of the second signal within a given time period.

[0029] Optionally, also include:

[0030] If the first signal is detected to indicate that the pressure of the force sensor is reduced or the second signal is detected to indicate that the capacitance detected by the mutual capacitance detection module is less than the first baseline, the current round of detection is stopped and the process returns to the step of obtaining the first signal.

[0031] In a third aspect, the present application provides an electronic touch device, including the mutual-capacitance touch product triggering device.

[0032] It can be seen that in this application, the force sensor and the mutual capacitance detection module are used to detect the touch signal applied to the touch product in coordination. Since the Shiled electrode provides a potential equal to that of the Tx electrode, the water droplets falling on the touch surface of the touch product are equal to the potential of the environment, so as to shield the influence of the water droplets on the mutual capacitance between the Tx electrode and the Rx electrode when they only contact the Tx electrode or the Rx electrode; at the same time, the force sensor can detect the pressure when the finger touches the touch surface of the touch product. It can be seen that this application reasonably avoids the awakening of the touch function when water droplets fall on the touch product, and solves the problem of false touch caused by conductors such as water droplets contacting mutual capacitance products. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0034] Figure 1 A diagram of a mutual-capacitance touch product triggering device provided in an embodiment of the present application;

[0035] Figure 2 A mutual capacitance schematic diagram provided for an embodiment of the present application;

[0036] Figure 3 A mutual capacitance equivalent circuit diagram provided in an embodiment of the present application;

[0037] Figure 4 A schematic diagram of finger touch during mutual capacitance provided by the prior art;

[0038] Figure 5 An equivalent circuit diagram of finger touch in mutual capacitance provided by an embodiment of the present application;

[0039] Figure 6 An equivalent circuit diagram of the effect of water droplets on mutual capacitance during mutual capacitance provided in an embodiment of the present application;

[0040] Figure 7 A touch detection flow chart provided in an embodiment of the present application;

[0041] Figure 8 A touch detection flow chart provided in an embodiment of the present application;

[0042] Fig. 9 A touch detection flow chart provided in an embodiment of the present application;

[0043] Fig.10 A detection diagram of a mutual-capacitance touch product trigger device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The core of this application is to provide a mutual-capacitance touch product trigger device.

[0046] In order to enable those skilled in the art to better understand the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0047] Mutual capacitance touch technology is a technology based on the principle of capacitive sensing and is widely used in electronic touch devices. In a mutual capacitance touch system, there are transmitting electrodes and receiving electrodes. When a conductive object such as a finger approaches the touch panel, it changes the mutual capacitance between the electrodes. The touch controller determines the touch position by detecting these changes in capacitance. Figure 1 As shown in the figure, the Tx electrode is the transmitting electrode and the Rx electrode is the receiving electrode. When the finger touches the Rx electrode and the Tx electrode, Figure 2 As shown in Figure 2, the mutual capacitance between the Rx electrode and the Tx electrode decreases. When the water droplet contacts the Rx electrode and the Tx electrode, as shown in Figure 2, the mutual capacitance between the Rx electrode and the Tx electrode decreases. Figure 3 As shown, an inductive capacitance Cf is generated between the water droplets and the Rx electrode and the Tx electrode, which is equivalent to two inductive capacitances connected in series and in parallel with the original Cm capacitance. The water droplets increase the equivalent mutual capacitance between the Rx electrode and the Tx electrode.

[0048] If the water droplets stay for a while and then are removed, the equivalent mutual capacitance between the Rx electrode and the Tx electrode becomes smaller, similar to the reduction in mutual capacitance caused by a finger touch, thus causing false touches.

[0049] It can be seen that how to solve the false touch caused by conductors such as water droplets contacting mutual capacitance products is a technical problem that needs to be solved urgently by people in this field.

[0050] See also Figure 1 and Figure 2 As shown, in order to solve the above problems, this embodiment discloses a mutual capacitance touch product triggering device, including: a force sensor, a mutual capacitance detection module and an MCU;

[0051] The mutual capacitance detection module includes: a group of Tx electrodes, Rx electrodes and Shiled electrodes, wherein the Tx electrodes, Rx electrodes, Shiled electrodes and force sensors are all arranged between the electrode attachment and support materials and the covering protective layer;

[0052] The shiled electrode surrounds the Tx electrode and the Rx electrode and is used to provide an electric potential equal to that of the Tx electrode;

[0053] The Tx electrode is used to transmit electrical signals, and the Rx electrode is used to receive electrical signals. The two electrodes are coupled to form mutual capacitance;

[0054] The MCU is connected to the Tx electrode, the Rx electrode, the Shiled electrode and the force sensor, and is used to provide an equipotential voltage source for the Tx electrode and the Shiled electrode, and receive a first signal representing the pressure on the force sensor and a second signal representing the equivalent mutual capacitance between the Tx electrode and the Rx electrode, and then determine whether to trigger the touch function based on the first signal and the second signal.

[0055] like Figure 2 As shown in the figure, Overlay is a protective layer, Printed Circuit Board (PCB) is the attachment and support material of the electrode, and mutual capacitance refers to the capacitance between the Rx electrode and the Tx electrode. Figure 3 The equivalent circuit diagram between the Rx electrode and the Tx electrode is shown in Figure 2. The sensor and the Rx port near the Rx port together form the Rx electrode, and the sensor and the Tx port near the Tx port together form the Tx electrode. There is a mutual capacitance Cm between the Tx electrode and the Rx electrode, and there is a measurement capacitance Cp1 between the Rx electrode and the ground. In the traditional mutual capacitance detection module, only the Rx electrode and the Tx electrode are included: the Tx electrode is used to transmit electrical signals, and the Rx electrode is used to receive electrical signals. The two electrodes are coupled to form mutual capacitance. Figure 4 As shown in FIG. 1 , since the volume and spacing of the Rx electrode and the Tx electrode are small, when the finger touches the touch point, it touches the Rx electrode and the Tx electrode at the same time. At this time, the equivalent circuit is as follows: Figure 5 As shown in FIG. 1 , the finger forms an inductive capacitor with the Rx electrode and the Tx electrode respectively, and is grounded at the same time. When a water drop contacts the Rx electrode and the Tx electrode, due to the small volume of the water drop, there are many situations that cause false touches.

[0056] In a specific embodiment, when the water drop only contacts the Rx electrode or the Tx electrode, an inductive capacitor Cf is formed between the water drop and the Rx electrode or the Tx electrode, and the mutual capacitance Cm between the Rx electrode and the Tx electrode is reduced. In the embodiment of the present application, a Shiled electrode is added to the mutual capacitance detection module, and the Shiled electrode has an equipotential potential with the Tx electrode. Since the water drop and the environment have the same potential, the influence of the water drop on the mutual capacitance Cm between the Rx electrode and the Tx electrode is eliminated.

[0057] In another specific embodiment, Figure 6 As shown in the figure, the water droplet simultaneously generates an inductive capacitance Cf between the Rx electrode and the Tx electrode, which is equivalent to two inductive capacitances connected in series and in parallel with the original mutual capacitance Cm. At this time, the water droplet increases the equivalent mutual capacitance between the Rx electrode and the Tx electrode. If the water droplet stays for a period of time and is then removed, the equivalent mutual capacitance between Rx and Tx decreases, similar to the process of mutual capacitance reduction caused by finger touch, thus causing false touches. At this time, it is necessary to cooperate with the force sensor to detect the touch signal applied to the touch product to avoid false touches.

[0058] Therefore, in a specific embodiment, the Tx electrode, the Rx electrode and the Shiled electrode appear in a group, while the force sensor does not appear in a group with the mutual capacitance detection module. They are often set in areas where false touches are easily formed when the touch product only has mutual capacitance sensors, or when the device needs to implement some advanced touch interaction functions, the mutual capacitance detection module and the force sensor may need to appear in pairs. For example, in a touch product with a 3DTouch function, each touch point where a mutual capacitance detection module is set requires a force sensor to detect the pressure. In this way, when the user touches the screen, the two work together to accurately sense the touch position and pressure level, thereby achieving different operations under different pressures.

[0059] It is understandable that selectively placing force sensors at specific locations can control costs to a certain extent. Mutual capacitance detection modules are relatively low in cost, and by increasing the number of mutual capacitance detection modules, good touch position detection accuracy can be ensured. However, force sensors are relatively expensive, and placing force sensors at key locations can meet the pressure sensing needs that most users may have during use.

[0060] It can be seen that in the embodiment of the present application, the force sensor and the mutual capacitance detection module are used to detect the touch signal applied to the touch product in coordination. Since the Shiled electrode provides a potential equal to that of the Tx electrode, the water droplets falling on the touch surface of the touch product are equal to the environment, so as to shield the influence of the water droplets on the mutual capacitance between the Tx electrode and the Rx electrode when they only contact the Tx electrode or the Rx electrode; at the same time, the force sensor can detect the pressure when the finger touches the touch surface of the touch product. It can be seen that the present application reasonably avoids the awakening of the touch function when water droplets fall on the touch product, and solves the problem of false touch caused by conductors such as water droplets contacting mutual capacitance products.

[0061] According to the above embodiments, this embodiment provides a specific solution, in which the force sensor is arranged below the mutual capacitance detection module.

[0062] In a specific embodiment, since the mutual capacitance detection module is mainly used to detect the position information of the touch product when it is touched, the position of the finger is sensed by detecting the change in mutual capacitance caused by the touch. Because the touch operation is first of all the contact between the finger and the screen surface, placing the mutual capacitance detection module closer to the touch surface can capture the touch position signal more sensitively and accurately. The force sensor is used to detect the pressure. When the finger presses the screen, the pressure can be transmitted through the upper mutual capacitance detection module and / or the covering layer. Placing the force sensor in the lower layer can realize the reception and measurement of the pressure after transmission, avoiding the interference of the touch position signal caused by the force sensor above the mutual capacitance detection module. It can be understood that the position of the force sensor and the mutual capacitance detection module is set to be adjacent to each other in the same layer, and the touch position of the touch product can be more accurately identified.

[0063] In a specific embodiment, the force sensor can be a spring force sensor. The spring force sensor works based on the strain effect. When subjected to external force, the spring will deform slightly. There is a copper-clad area at the position corresponding to the spring force sensor on the PCB circuit board. An inductive capacitor is formed between the copper-clad area and the metal spring of the force sensor. The deformation of the spring will cause the distance between the copper-clad area and the spring to change, which in turn causes the capacitance value of the strain gauge pasted on the spring to change. By measuring this capacitance change, the pressure can be accurately calculated, which can meet the high-precision requirements of the touch device for pressure perception and achieve accurate distinction between different pressure levels. At the same time, the spring itself has a certain elasticity and can quickly deform with the application of external force, so that the strain gauge can quickly sense the pressure change and generate a corresponding electrical signal. It has high sensitivity and fast response capability, and can provide real-time feedback on the change of touch pressure. It is understandable that the force sensor here can also be an optoelectronic sensor, an ultrasonic force sensor, a piezoresistive force sensor, a Hall force sensor, etc.

[0064] According to the above embodiment, this embodiment provides a specific solution, wherein there are multiple mutual capacitance detection modules, and the multiple mutual capacitance detection modules are connected to the same MCU.

[0065] In a specific implementation, the same multiple groups of sensors can be connected to the same MCU. This architecture can effectively integrate the touch detection function, thereby facilitating unified control and coordination of all mutual capacitance detection modules. At the same time, the MCU can communicate with other system components, such as display screens, audio modules, communication modules, etc. The second signal collected by the mutual capacitance detection module is combined with other functions to achieve richer product functions. In addition, using one MCU to manage multiple touch detection modules can reduce hardware costs and circuit board space. Compared with equipping each touch detection module with an independent processor, one MCU can centrally process all touch information, improving the utilization of hardware resources.

[0066] According to the above embodiment, this embodiment provides a specific solution, the Tx electrode, the Rx electrode and the Shiled electrode are connected to the signal end that sends the fixed sequence charge and discharge signal. The mutual capacitance detection module realizes touch detection through the fixed sequence charge and discharge signal of the transmitting electrode, the receiving electrode and the protection electrode. The equivalent circuit diagram is as follows Figure 3 When the capacitor is continuously charged and maintained in a fully charged state, the branch where it is located is equivalent to an open circuit. Therefore, a pulse signal with a suitable interval makes the mutual capacitance Cm measurable, thereby realizing the detection of the change of the mutual capacitance Cm by the touch signal. Figure 7 This embodiment discloses a mutual-capacitance touch product triggering method, which is applied to the aforementioned touch product triggering device, and includes:

[0067] Step S11, acquiring a first signal representing a pressure change of the force sensor and a second signal representing a capacitance change detected by a mutual capacitance detection module.

[0068] In this embodiment, the MCU is connected to the mutual capacitance detection module and the force sensor, and simultaneously receives a first signal representing a pressure change of the force sensor and a second signal representing a capacitance change detected by the mutual capacitance detection module. It can be seen from the above embodiment that the force sensor and the mutual capacitance detection module do not appear in a group, and when there is only the mutual capacitance detection module, only the second signal is collected.

[0069] Step S12: determining whether the touch function is triggered according to the first signal and the second signal.

[0070] In this embodiment, when the water droplets contact the Rx electrode and the Tx electrode at the same time, Figure 6 As shown in the figure, the water droplets generate inductive capacitance Cf between the Rx electrode and the Tx electrode respectively, which is equivalent to two inductive capacitances connected in series and in parallel with the original mutual capacitance Cm. At this time, the water droplets are equivalent to increasing the mutual capacitance between the Rx electrode and the Tx electrode. If the water droplets stay for a period of time and then removed, the equivalent mutual capacitance between Rx and Tx will decrease, similar to the process of mutual capacitance reduction caused by finger touch, thus causing false touches. At this time, it is necessary to cooperate with the force sensor to detect the touch signal applied to the touch product to avoid false touches.

[0071] According to the above embodiment, this embodiment provides a specific solution, and judging whether to trigger the touch function according to the first signal and the second signal includes:

[0072] Step S21, detecting a first signal transmitted by the force sensor;

[0073] In this embodiment, the force sensor detects the external pressure signal that the touch product is subjected to. Compared with the change in the force sensor detection value caused by finger pressing, the change in the force sensor detection value caused by water droplets is very small because the water droplets are lighter. Therefore, the force sensor can be used to help eliminate accidental touches of the touch product caused by water droplets.

[0074] Step S22: If the first signal meets a first condition, the second signal transmitted by the mutual capacitance detection module is detected, and the first condition is: the pressure increase of the force sensor reflected by the first signal is greater than a first threshold value;

[0075] In this embodiment, the pressure detection result is queried first. If the force sensor is not triggered, it is considered that it is not a normal finger touch and press action, and the touch product function is not triggered. If the force sensor is triggered and the touch sensor is triggered, it is considered that it is a normal finger touch and press action, and the touch product function is triggered normally.

[0076] Step S23: If the second signal meets the second condition, the touch product function is triggered, and the second condition is that the capacitance detected by the mutual capacitance detection module reflected by the second signal is greater than the first baseline and the difference between the two is greater than the threshold, and the threshold is a sensitivity-related variable; if the first signal does not meet the first condition or the second signal does not meet the second condition, it is determined that the current touch operation is a false touch operation.

[0077] In this embodiment, when the force sensor and the mutual capacitance detection module are triggered at the same time, the first signal and the second signal are determined to be from a finger touch. When the first signal meets the first condition but the second signal does not meet the second condition, or the first signal does not meet the first condition, the touch event is determined to be a false touch.

[0078] Figure 3 A mutual capacitance equivalent circuit diagram provided in an embodiment of the present application is as follows: Figure 3 As shown, according to the above embodiment, this embodiment provides a specific solution for obtaining a second signal representing a capacitance change detected by a mutual capacitance detection module, including:

[0079] Step S31, discharging the mutual capacitance and the measurement capacitance of the Tx electrode and the Rx electrode until the charge amounts of the mutual capacitance and the measurement capacitance are zero.

[0080] In this embodiment, the first step is full discharge: at the beginning of the entire charge and discharge measurement cycle, all the charges on the mutual capacitance Cm and the measurement capacitor Cp1 are discharged.

[0081] Step S32, setting the Tx electrode to a high potential and the Rx electrode to a low potential, so that the mutual inductance capacitor short-circuits the Tx electrode and the Rx electrode, and charges the mutual inductance capacitor.

[0082] In this embodiment, the second step is charging: the Tx electrode is set to a high potential, the Rx electrode is set to a low potential, the measuring capacitor Cp1 is disconnected from the mutual capacitance Cm and the Rx electrode, Cm short-circuits the Tx electrode and the Rx electrode, and the signal end charges the mutual capacitance Cm.

[0083] Step S33, the Tx electrode and the Rx electrode disconnect the input of the electrical signal, so that the mutual capacitance short-circuits the measuring capacitance to transfer all the charges to the measuring capacitance until the measuring capacitance voltage is greater than the reference voltage. If the measuring capacitance voltage is less than the reference voltage, the mutual capacitance charging step is returned.

[0084] In this embodiment, the third step is transfer: disconnecting the Tx electrode from the signal end, disconnecting the Rx electrode from the signal end, short-circuiting the measuring capacitor Cp1 and the mutual capacitance Cm, disconnecting the measuring capacitor Cp1 from the Rx electrode, and partially transferring the charge on the mutual capacitance Cm to the measuring capacitor Cp1.

[0085] Step S34, counting the number of times the mutual inductance capacitor is charged, and recording the number of times the mutual inductance capacitor is charged as a second signal.

[0086] In this embodiment, the fourth step is measurement: the comparator is used to compare the reference voltage Vref and the voltage across the measurement capacitor Cp1. If the voltage across the measurement capacitor Cp1 > Vref, the entire charge-discharge measurement cycle ends, and the number of charging times during the entire process is recorded; if the voltage across the measurement capacitor Cp1 < Vref, the charging, transfer, and measurement processes are repeated until the voltage across the measurement capacitor Cp1 > Vref and the entire measurement cycle ends.

[0087] As Figure 5 shown, if a finger touches, since the human body is in a high-impedance state, it is equivalent to ground for high-frequency signals during the charge-discharge measurement cycle. For a single charging process, part of the charge emitted by the Tx electrode is shunted by the sensing capacitance Cf of the finger, resulting in less charge on the mutual capacitance Cm, which is equivalent to the finger touch reducing the mutual capacitance Cm. Therefore, after the finger touches, during the transfer process, less charge can be transferred from the mutual capacitance Cm to Cp1, and since V = Q / C, the number of charging times for the voltage across the measurement capacitor Cp1 to reach the reference voltage Vref becomes more. Furthermore, the change in the mutual capacitance is characterized by the number of charging times.

[0088] According to the above embodiment, this embodiment provides a specific solution where the first reference line is a time-related variable;

[0089] When the duration for which the second signal is maintained exceeds the time threshold, the first reference line exhibits an asymptotic change and gradually approaches the value of the second signal within a given time period.

[0090] Fig.10 This is a detection diagram of a mutual capacitance type touch product triggering device provided by an embodiment of the present application. As Fig.10 shown, the green line is the reference line Baseline, and the orange line is the number of charging times of the measured mutual capacitance Cm. When the orange line remains at a fixed value with a fluctuation amplitude not exceeding the preset error and the duration is greater than the time threshold, the green reference line follows the orange second signal line to adapt to measurement events under different environments and device states. For example, due to temperature changes, electromagnetic interference, etc., causing an overall increase or decrease in the number of charging times, the reference line should change accordingly.

[0091] According to the above embodiment, this embodiment provides a specific solution, which further includes:

[0092] If it is detected that the first signal indicates a decrease in the pressure of the force sensor or it is detected that the capacitance detected by the second signal representing the mutual capacitance detection module is less than the first reference line, this round of detection is stopped, and the step of obtaining the first signal is returned.

[0093] Since errors are inevitable in the measurement data, when the second signal represents that the capacitance detected by the mutual capacitance detection module is less than the first baseline, it is determined that there is an error in the second signal value, and the step of obtaining the first signal is returned to improve the measurement accuracy.

[0094] In order to make the working principle of the present application more clear to those skilled in the art, the following will describe in detail different situations. The collected second signal detection diagram, the second signal is characterized by the number of times the equivalent mutual capacitance is charged from zero to the reference voltage, Fig.10 A detection diagram of a mutual-capacitance touch product trigger device provided in an embodiment of the present application, such as Fig.10 As shown, the orange line is the second signal line, and the green line is the baseline. There are five situations: finger touch (Finger-Touch), liquid droplet contacts the Tx electrode and the shield electrode (Liquid-droplet-on-the-Tx-and-grounded-shield-hatch), liquid drop contacts the Tx electrode and the Rx electrode at the same time (Liquid-drop-present-on-the-Tx-electrode-and-Rx-electrode-only), finger touch when there are liquid drops only on the Tx electrode and the Rx electrode (Finger-Touch-when-Liquid-drop-on-the-Tx-electrode-and-Rx-electrode-only) and liquid drop is removed from the Tx electrode and the Rx electrode (Liquid-drop-removed-from-the-Tx-electrode-and-Rx-electrode).

[0095] In the first case, a finger touches the touch screen. At this time, the mutual capacitance Cm decreases greatly, and the difference between the orange second signal line and the green baseline is greater than the threshold, triggering the touch function.

[0096] In the second case, the droplet contacts the Tx electrode and the shield electrode. At this time, due to the existence of the shiled electrode, the change in mutual capacitance Cm is small and is not enough to trigger the touch function.

[0097] In the third case, the droplet contacts the Tx electrode and the Rx electrode at the same time. At this time, the water droplet generates an inductive capacitance Cf between the Rx electrode and the Tx electrode, which is equivalent to connecting two inductive capacitances in series and in parallel with the original mutual capacitance Cm. At this time, the water droplet increases the equivalent mutual capacitance between the Rx electrode and the Tx electrode, and the charging times decrease. After the water droplet stays for a long time, the green baseline follows the change of the orange second signal line.

[0098] The fourth case is when there are only droplets on the Tx electrode and the Rx electrode when the finger touches. At this time, the finger also reduces the equivalent mutual capacitance, and the number of charging times increases.

[0099] In the fifth case, when the water droplets are removed from the Tx electrode and the Rx electrode, the equivalent mutual capacitance between Rx and Tx decreases, similar to the mutual capacitance reduction process caused by finger touch, thus causing false touches. At this time, it is necessary to cooperate with the force sensor to detect the touch signal applied to the touch product to avoid false touches.

[0100] Finally, this embodiment provides an electronic touch device, including the above-mentioned mutual-capacitance touch product triggering device.

[0101] The above is a detailed introduction to a mutual-capacitance touch product triggering device, method and electronic touch device provided by the present application. The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can refer to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can refer to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

[0102] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A mutual-capacitance touch product trigger device, characterized in that: include: Force sensor, mutual capacitance detection module and MCU; The mutual capacitance detection module comprises: a group of Tx electrodes, Rx electrodes and Shiled electrodes, wherein the Tx electrodes, the Rx electrodes, the Shiled electrodes and the force sensor are all arranged between the electrode attachment and support materials and the covering protective layer; The Shiled electrode surrounds the Tx electrode and the Rx electrode and is used to provide a potential equal to that of the Tx electrode; The Tx electrode is used to transmit an electrical signal, and the Rx electrode is used to receive an electrical signal, and the two electrodes are coupled to form mutual capacitance; The MCU is connected to the Tx electrode, the Rx electrode, the Shiled electrode and the force sensor, and is used to provide an equipotential voltage source for the Tx electrode and the Shiled electrode, and receive a first signal representing the pressure on the force sensor and a second signal representing the equivalent mutual capacitance between the Tx electrode and the Rx electrode, and then determine whether to trigger the touch function based on the first signal and the second signal.

2. The mutual-capacitance touch product triggering device according to claim 1, characterized in that: The force sensor is arranged below the mutual capacitance detection module.

3. The mutual-capacitance touch product triggering device according to claim 1, characterized in that: There are multiple mutual capacitance detection modules, and the multiple mutual capacitance detection modules are connected to the same MCU.

4. The mutual-capacitance touch product triggering device according to any one of claims 1 to 3, characterized in that: The Tx electrode, the Rx electrode and the Shiled electrode are connected to a signal end that sends a fixed sequence charge and discharge signal.

5. A mutual-capacitance touch product triggering method, applied to the touch product triggering device according to any one of claims 1 to 4, characterized in that: include: Acquire a first signal representing a pressure change of the force sensor and a second signal representing a capacitance change detected by a mutual capacitance detection module; Whether a touch function is triggered is determined according to the first signal and the second signal.

6. The method for triggering a mutual-capacitive touch product according to claim 5, characterized in that: Determining whether to trigger a touch function according to the first signal and the second signal includes: detecting the first signal transmitted by the force sensor; If the first signal meets a first condition, the second signal transmitted by the mutual capacitance detection module is detected, and the first condition is: the pressure increase of the force sensor reflected by the first signal is greater than a first threshold value; If the second signal meets the second condition, the touch product function is triggered, and the second condition is that the capacitance value detected by the mutual capacitance detection module reflected by the second signal is greater than the first baseline and the difference between the two is greater than a threshold value, and the threshold value is a sensitivity-related variable; If the first signal does not satisfy the first condition or the second signal does not satisfy the second condition, it is determined that the current touch operation is an incorrect touch operation.

7. The method for triggering a mutual-capacitive touch product according to claim 5, characterized in that: Acquiring a second signal representing a capacitance change detected by the mutual capacitance detection module includes: Discharging the mutual capacitance and the measurement capacitance of the Tx electrode and the Rx electrode until the charge amounts of the mutual capacitance and the measurement capacitance are zero; Setting the Tx electrode to a high potential and the Rx electrode to a low potential, so that the mutual inductance capacitor short-circuits the Tx electrode and the Rx electrode, and charges the mutual inductance capacitor; The Tx electrode and the Rx electrode disconnect the input of the electrical signal, so that the mutual capacitance shorts the measuring capacitance to transfer all the charges to the measuring capacitance until the measuring capacitance voltage is greater than the reference voltage. If the measuring capacitance voltage is less than the reference voltage, the mutual capacitance charging step is returned; The mutual capacitance charging times are counted, and the mutual capacitance charging times are recorded as the second signal.

8. The method for triggering a mutual-capacitive touch product according to claim 6, characterized in that: The first baseline is a time-related variable; When the duration of the second signal exceeds a time threshold, the first baseline changes asymptotically, gradually approaching the value of the second signal within a given time period.

9. The method for triggering a mutual-capacitive touch product according to claim 6, characterized in that: Also includes: If the first signal is detected to indicate that the pressure of the force sensor is reduced or the second signal is detected to indicate that the capacitance detected by the mutual capacitance detection module is less than the first baseline, the current round of detection is stopped and the process returns to the step of obtaining the first signal.

10. An electronic touch device, characterized in that: The invention comprises the trigger device of a mutual-capacitance touch product as described in any one of claims 1 to 9.

Images