A mutual capacitance detection circuit with voltage regulation function and a mutual capacitance detection system

Abstract

A mutual capacitance detection circuit with a voltage regulation function and a mutual capacitance detection system with a voltage regulation function, the mutual capacitance detection circuit comprising: a voltage regulation module, a sensing module and a receiving module; the voltage regulation module outputs a voltage scanning signal after regulating an input voltage according to a received control signal; the sensing module outputs a response signal according to the voltage scanning signal; the sensing module comprises at least one sensing electrode and driving electrodes having the same number as the sensing electrodes, the sensing electrodes and the driving electrodes are arranged in a one-to-one correspondence, the driving electrodes are used to receive and transmit the voltage scanning signal, so that the sensing electrodes generate a response signal, and the response signal responds to the change in the operating parameter of the driving electrode driven by the voltage scanning signal; the receiving module obtains the change in the mutual capacitance between the driving electrode and the sensing electrode according to the response signal; the mutual capacitance detection circuit has a more flexible voltage regulation function, simplifies the circuit structure, and reduces the voltage regulation cost in mutual capacitance detection.

Description

Technical Field

[0001] The present invention belongs to the technical field of mutual capacitance detection, and in particular relates to a mutual capacitance detection circuit with a voltage regulation function and a mutual capacitance detection system with a voltage regulation function. Background Art

[0002] In the parameter detection technology of electronic circuits, mutual capacitance is an important parameter and is widely used in various technical fields such as fingerprint recognition and pressure detection systems. When the sensing block receives external disturbance, the mutual capacitance between adjacent sensing blocks will change accordingly. The actual change of the external disturbance can be obtained according to the change of mutual capacitance, and then the circuit parameter information required by the user can be obtained. Taking the capacitive fingerprint recognition system as an example, since the fingerprints of the user's fingers have different depths, as the fingerprints of the fingers press the sensing block, the mutual capacitance between the sensing blocks will change accordingly with the pressure of the fingerprint lines, and then the actual structural information of the user's fingerprint lines can be directly obtained by detecting the mutual capacitance between the sensing blocks. Therefore, real-time detection is performed through the change of mutual capacitance, and then the specific fingerprint line information of the user is accurately obtained. In addition, the mutual capacitance detection process is relatively simple, and the detection sensitivity is extremely high. Therefore, the actual structural information of the circuit can be obtained in real time by detecting the mutual capacitance.

[0003] However, in the process of mutual capacitance detection, it is necessary to change the amplitude of the input signal of the sensing block, and then detect the output signal of the adjacent sensing block to obtain the actual mutual capacitance change information, such as changing the voltage of the sensing block to obtain the corresponding output, and then determine whether the mutual capacitance of the adjacent sensing blocks has changed; the mutual capacitance detection circuit of the traditional technology has a small voltage regulation range, and technicians usually need to use auxiliary components such as inductors and voltage stabilizing circuits to change the voltage of the sensing block to increase the voltage regulation range; this voltage regulation method requires a large number of additional electronic components, resulting in a more complex circuit design of the mutual capacitance detection circuit, a larger circuit space, and higher manufacturing and application costs.

[0004] Therefore, the voltage regulation steps of the mutual capacitance detection circuit in the traditional technology are too complicated, which increases the circuit structure complexity and design cost of the capacitance detection circuit, and brings great inconvenience to the mutual capacitance detection. Summary of the invention

[0005] In view of this, an embodiment of the present invention provides a mutual capacitance detection circuit with a voltage regulation function and a mutual capacitance detection system with a voltage regulation function, aiming to solve the problem that the voltage regulation function of the mutual capacitance detection circuit in the traditional technical solution is low in flexibility, resulting in a more complex structure of the mutual capacitance detection circuit, an increase in its own space volume, and excessively high voltage regulation costs during the mutual capacitance detection process.

[0006] A first aspect of an embodiment of the present invention provides a mutual capacitance detection circuit with a voltage regulation function, including:

[0007] A voltage regulating module, used for regulating the input voltage according to the received control signal and then outputting a voltage scanning signal;

[0008] a sensing module connected to the voltage regulating module, the sensing module being used to output a response signal according to the voltage scanning signal; the sensing module comprising at least one sensing electrode and driving electrodes having the same number as the sensing electrodes, the sensing electrodes being arranged in a one-to-one correspondence with the driving electrodes, the driving electrodes being used to receive and transmit the voltage scanning signal so that the sensing electrodes generate the response signal, the response signal being in response to a change in an operating parameter of the driving electrode driven by the voltage scanning signal; and

[0009] A receiving module is connected to the sensing module, and is used to obtain a change in mutual capacitance between the driving electrode and the sensing electrode according to the response signal.

[0010] In one embodiment, the voltage regulation module includes:

[0011] A voltage access unit is connected to N first drive voltages and M first reference voltages, and the voltage access unit is used to be turned on or off according to a first control signal to output a first positive potential signal and M first negative potential signals, and to be turned on or off according to a second control signal to output a second positive potential signal and M second negative potential signals;

[0012] At least one voltage processing unit, each of which is connected to a logic control signal, and is used to perform potential conversion processing on the logic control signal to obtain a voltage driving signal; and

[0013] at least one switch control unit, the switch control unit being connected to the voltage access unit, and the switch control unit being connected to the voltage processing unit in a one-to-one correspondence, the switch control unit being connected to the drive electrodes in a one-to-one correspondence, and the switch control unit being used to conduct or shut down according to the inverted signal of the logic control signal, the first drive voltage, and the negative electrode potential signal output by the voltage access unit, so as to convert the voltage drive signal into the voltage scanning signal;

[0014] The negative electrode potential signal output by the voltage access unit is the first negative electrode potential signal or the second negative electrode potential signal, N is a positive integer greater than 1, M is a positive integer greater than 0, and N=M+1.

[0015] In one embodiment, the first driving voltage, the first reference voltage, the first positive potential signal, the first negative potential signal, the second positive potential signal, the logic control signal and the second negative potential signal satisfy the following relationship:

[0016] VPWR>VGND;

[0017] VSSTX1 = VGND;

[0018] VDDTX1 = VPWR;

[0019] VSSTX2 = (Ni) * VPWR;

[0020] VDDTX2 = N*VPWR;

[0021] VIN1 = VPWR;

[0022] VIN2 = VGND;

[0023] In the above formula, VPWR is the amplitude of the first driving voltage, VGND is the amplitude of the first reference voltage, VSSTX1 is the voltage amplitude of the first negative potential signal, VDDTX1 is the voltage amplitude of the first positive potential signal, VSSTX2 is the voltage amplitude of the second negative potential signal, and VDDTX2 is the voltage amplitude of the second positive potential signal; VIN1 is the high level amplitude of the logic control signal, VIN2 is the low level amplitude of the logic control signal, and i is a positive integer greater than 0 and less than N.

[0024] In one embodiment, when M=1, the voltage access unit includes:

[0025] A first switch tube, a second switch tube, a third switch tube and a first capacitor;

[0026] The first conducting end of the first switch tube is connected to the first driving voltage, the control end of the first switch tube is connected to the first control signal, the second conducting end of the first switch tube and the first end of the first capacitor are connected together to form the positive output end of the voltage access unit, and the positive output end of the voltage access unit outputs the first positive potential signal or the second positive potential signal;

[0027] The second end of the first capacitor, the first conduction end of the second switch tube, and the first conduction end of the third switch tube are connected together to form a negative output end of the voltage access unit, and the negative output end of the voltage access unit outputs the first negative potential signal or the second negative potential signal;

[0028] The control end of the second switch tube is connected to the first control signal;

[0029] The control terminal of the third switch tube is connected to the second control signal;

[0030] The second conduction end of the second switch tube is connected to the first reference voltage;

[0031] The second conduction end of the third switch tube is connected to the first driving voltage.

[0032] In one embodiment, the switch control unit includes:

[0033] a fourth switch tube, a fifth switch tube and a sixth switch tube;

[0034] The first conduction end of the fourth switch tube is connected to the voltage processing unit, the control end of the fourth switch tube is connected to the first negative electrode potential signal or the second negative electrode potential signal, the second conduction end of the fourth switch tube and the first conduction end of the fifth switch tube are connected together to form a signal output end of the switch control unit, and the signal output end of the switch control unit is used to output the voltage scanning signal;

[0035] The control terminal of the fifth switch tube is connected to the first driving voltage;

[0036] The second conduction terminal of the fifth switch tube is connected to the first conduction terminal of the sixth switch tube;

[0037] The second conduction terminal of the sixth switch tube is connected to the first reference voltage, and the control terminal of the sixth switch tube is connected to the inverted signal of the logic control signal.

[0038] In one embodiment, when M>1, the voltage access unit includes:

[0039] A seventh switch tube, an eighth switch tube, a ninth switch tube, a second capacitor and a switch array;

[0040] The first conduction end of the seventh switch tube is connected to the first driving voltage, the control end of the seventh switch tube is connected to the first control signal, the second conduction end of the seventh switch tube and the first end of the second capacitor are connected together to form the positive output end of the voltage access unit, and the positive output end of the voltage access unit outputs the first positive potential signal or the second positive potential signal;

[0041] The first conduction terminal of the eighth switch tube is connected to the first reference voltage, and the control terminal of the eighth switch tube is connected to the first control signal;

[0042] The first conduction terminal of the ninth switch tube is connected to the first driving voltage, and the control terminal of the ninth switch tube is connected to the second control signal;

[0043] The switch array includes M-1 switch drive units, a voltage input terminal of a preceding switch drive unit is connected to a voltage output terminal of a succeeding switch drive unit, a voltage output terminal of the first switch drive unit is connected to a second terminal of the second capacitor, and a voltage input terminal of the last switch drive unit is connected to a second conduction terminal of the eighth switch tube and a second conduction terminal of the ninth switch tube;

[0044] The voltage output end of the first switch driving unit is used to output one of the first negative electrode potential signals or one of the second negative electrode potential signals; the voltage input end of each switch driving unit outputs one of the first negative electrode potential signals or one of the second negative electrode potential signals;

[0045] Each of the switch driving units includes: a tenth switch tube, an eleventh switch tube, a twelfth switch tube and a third capacitor;

[0046] The first conduction end of the tenth switch tube is connected to the first reference voltage, the control end of the tenth switch tube is connected to the first control signal, the second conduction end of the tenth switch tube and the first conduction end of the eleventh switch tube are connected together to form the voltage output end of the switch driving unit, the control end of the eleventh switch tube is connected to the second control signal, the second conduction end of the eleventh switch tube and the first conduction end of the twelfth switch tube are connected together to the first end of the third capacitor, the control end of the twelfth switch tube is connected to the first control signal, and the second conduction end of the twelfth switch tube is connected to the first driving voltage; the second end of the third capacitor is the voltage input end of the switch driving unit.

[0047] In one embodiment, the switch control unit includes:

[0048] A thirteenth switch tube, a fourteenth switch tube and a voltage clamping unit;

[0049] The first conduction end of the thirteenth switch tube is connected to the first reference voltage, the control end of the thirteenth switch tube is connected to the inverted signal of the logic control signal, the second conduction end of the thirteenth switch tube is connected to the first conduction end of the fourteenth switch tube, and the control end of the fourteenth switch tube is connected to the first driving voltage;

[0050] The voltage clamping unit includes a first voltage processor and a second voltage processor, the first voltage processor includes M fifteenth switch tubes, and the second voltage processor includes M-1 sixteenth switch tubes;

[0051] In the first voltage processor, the first conductive end of the first fifteenth switch tube is connected to the voltage processing unit, the second conductive end of the last fifteenth switch tube is connected to the driving electrode, the second conductive end of the first fifteenth switch tube is connected to the first conductive end of the next fifteenth switch tube, and the control end of each fifteenth switch tube is connected to a first negative electrode potential signal or a second negative electrode potential signal;

[0052] In the second voltage processor, the first conductive end of the first sixteenth switch tube is connected to the driving electrode, the second conductive end of the last sixteenth switch tube is connected to the second conductive end of the fourteenth switch tube, the second conductive end of the first sixteenth switch tube is connected to the first conductive end of the next sixteenth switch tube, and the control end of each sixteenth switch tube is connected to the negative control voltage;

[0053] The negative electrode control voltage is the voltage of the first end of the third capacitor in each of the switch driving units.

[0054] In one embodiment, the voltage processing unit includes:

[0055] A potential converter, wherein a signal input terminal of the potential converter is connected to the logic control signal, and the potential converter is used to adjust the level amplitude of the logic control signal;

[0056] A first inverter, wherein an input terminal of the first inverter is connected to a signal output terminal of the potential converter; and

[0057] A second inverter, wherein an input terminal of the second inverter is connected to an output terminal of the first inverter, and an output terminal of the second inverter is connected to the switch control unit.

[0058] In one embodiment, the voltage processing unit includes:

[0059] A seventeenth switch tube, an eighteenth switch tube, an OR gate, a third inverter, a fourth inverter and a fifth inverter;

[0060] The first input end of the OR gate is connected to the logic control signal, the second input end of the OR gate is connected to the second control signal, the output end of the OR gate is connected to the first conduction end of the seventeenth switch tube, the second conduction end of the seventeenth switch tube and the first conduction end of the eighteenth switch tube are commonly connected to the input end of the third inverter, the second conduction end of the eighteenth switch tube is connected to the output end of the fourth inverter, the output end of the third inverter and the input end of the fourth inverter are commonly connected to the input end of the fifth inverter, and the output end of the fifth inverter is connected to the switch control unit;

[0061] The control end of the seventeenth switch tube is connected to the third control signal, and the control end of the eighteenth switch tube is connected to the fourth control signal;

[0062] The fourth control signal is an inverted signal of the third control signal, and the voltage amplitude of the third control signal is the same as the first driving voltage.

[0063] A second aspect of an embodiment of the present invention provides a mutual capacitance detection system with a voltage regulation function, including:

[0064] A mutual capacitance detection circuit as described above; and

[0065] A power module is connected to the mutual capacitance detection circuit, and the power module is used to supply power to the mutual capacitance detection circuit.

[0066] The mutual capacitance detection circuit with voltage regulation function can generate voltage scanning signals with different amplitudes through the voltage regulation module, and the operating parameters of the driving electrode can be changed through the voltage scanning signal; when the operating parameters of the driving electrode change, the sensing electrode will sense the change in the operating parameters of the driving electrode, and output a response signal corresponding to the change in the operating parameters of the driving electrode, and then after processing and analyzing the response signal, the change in the mutual capacitance of the driving electrode and the sensing electrode can be accurately obtained, and the detection accuracy is extremely high; therefore, the embodiment of the present invention can arbitrarily adjust the voltage amplitude in the mutual capacitance detection process through the voltage regulation module, so that the sensing module changes its own operating parameters with voltage scanning signals of different voltage amplitudes, and detects the change response of the sensing module to obtain the characterization of the mutual capacitance; therefore, this embodiment has a more flexible voltage regulation function in the mutual capacitance detection process, and the voltage amplitude of the voltage scanning signal has a wider range of variation to achieve a high-precision detection function for the mutual capacitance; and the mutual capacitance detection circuit does not require additional auxiliary voltage stabilization components, and the voltage regulation process is relatively simple, which reduces the space volume of the circuit structure, simplifies the circuit structure of the mutual capacitance detection circuit, and is conducive to reducing the voltage regulation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0068] Figure 1 A schematic diagram of the structure of a mutual capacitance detection circuit with a voltage regulation function provided by an embodiment of the present invention;

[0069] Figure 2 A schematic diagram of the structure of a voltage regulation module provided in one embodiment of the present invention;

[0070] Figure 3 A schematic diagram of the circuit structure of a voltage access unit provided in one embodiment of the present invention;

[0071] Figure 4 A voltage amplitude waveform diagram of each control signal in a voltage access unit provided in an embodiment of the present invention;

[0072] Figure 5 A schematic diagram of the circuit structure of a switch control unit provided in one embodiment of the present invention;

[0073] Figure 6 Another schematic diagram of the circuit structure of a voltage access unit provided in one embodiment of the present invention;

[0074] Figure 7 Another schematic diagram of the circuit structure of a switch control unit provided in one embodiment of the present invention;

[0075] Figure 8 A schematic diagram of the circuit structure of a voltage processing unit provided in one embodiment of the present invention;

[0076] Fig. 9 Another schematic diagram of a circuit structure of a voltage processing unit provided in one embodiment of the present invention;

[0077] Fig.10 A schematic diagram of the structure of a mutual capacitance detection system with a voltage regulation function provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0078] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0079] It should be noted first that mutual capacitance refers to the capacitance between two adjacent electrodes. Unlike self-capacitance, mutual capacitance comes from the electric field generated by the mutual attraction between the two electrodes. When the external pressure is applied, the electric field decays to produce a change in capacitance. Moreover, the mutual capacitance between the two electrodes has higher detection accuracy and sensitivity for external pressure. Therefore, the mutual capacitance can be used to accurately monitor the circuit's own operating information, and the mutual capacitance between the two electrodes can also be detected more easily. Therefore, the detection of mutual capacitance can realize the accurate acquisition of various circuit information.

[0080] See also Figure 1 , Figure 1The structure of the mutual capacitance detection circuit 10 with voltage regulation function provided by an embodiment of the present invention is shown, wherein the mutual capacitance detection circuit 10 can adjust the voltage amplitude during the mutual capacitance detection process to complete the real-time and accurate detection function of the mutual capacitance, and the voltage regulation process is relatively simplified, thereby reducing the circuit structure design cost and application cost of the mutual capacitance detection circuit 10; for the sake of convenience of explanation, only the part related to this embodiment is shown, which is described in detail as follows:

[0081] The mutual capacitance detection circuit 10 includes: a voltage regulation module 101 , a sensing module 102 and a receiving module 103 .

[0082] The voltage regulating module 101 is used to adjust the input voltage according to the received control signal and then output a voltage scanning signal.

[0083] The control signal includes circuit on-off control information, and the voltage conversion state of the electronic components can be adjusted through the control signal. The voltage regulation module 101 changes the amplitude of the input voltage according to the control information in the control signal, so that the voltage regulation module 101 outputs a voltage scanning signal with different voltage amplitudes; the voltage scanning signal has a circuit driving function; and when the voltage regulation module 101 has different adjustment amplitudes for the input voltage, the mutual capacitance detection circuit 10 can be driven by the voltage scanning signal to implement the corresponding mutual capacitance detection function; this embodiment can change the working state of the voltage regulation module 101 in real time through the control signal, so that the mutual capacitance detection circuit 10 has higher detection accuracy for mutual capacitance detection, the voltage scanning signal has higher operability and flexibility, and the mutual capacitance detection process can fully meet the actual circuit function detection needs of technicians.

[0084] As an optional implementation, the control signal is generated by a control signal generating circuit, wherein the control signal generating circuit is implemented using a circuit structure in traditional technology; the control signal includes user operation information, and the voltage amplitude of the voltage scanning signal can be changed in real time through the control signal. The voltage conversion state of the voltage regulation module 101 has high control flexibility, and the mutual capacitance detection circuit 10 has high accuracy and stability for mutual capacitance detection. The mutual capacitance detection circuit 10 can meet the actual circuit function requirements of technicians for the detection of mutual capacitance changes, and has wide compatibility.

[0085] The sensing module 102 is connected to the voltage regulating module 101, and is used to output a response signal according to the voltage scanning signal; the sensing module 102 includes at least one sensing electrode RX and driving electrodes TX having the same number as the sensing electrodes RX, the sensing electrodes RX and the driving electrodes TX are arranged in a one-to-one correspondence, and the driving electrodes TX are used to receive and transmit the voltage scanning signal so that the sensing electrodes RX generate a response signal, and the response signal responds to the change in the operating parameter of the driving electrode TX driven by the voltage scanning signal.

[0086] Specifically, the voltage regulation module 101 is connected to the driving electrode TX, and information exchange can be achieved between the voltage regulation module 101 and the driving electrode TX; in the sensing module 102, the sensing electrode RX and the driving electrode TX have high conductivity, each sensing electrode RX and the driving electrode TX are relatively arranged, and a certain capacitive coupling is generated between the sensing electrode RX and the driving electrode TX, so that a certain potential difference is generated between the sensing electrode RX and the driving electrode TX, and a mutual capacitance of a specific amplitude is formed between the sensing electrode RX and the driving electrode TX, and the mutual capacitance stores part of the charge; the corresponding mutual capacitance can be adjusted by changing the relative position between the sensing electrode RX and the driving electrode TX and the power characteristic information of each electrode.

[0087] In this embodiment, when the voltage regulation module 101 transmits the voltage scanning signal to the driving electrode TX, the operating parameter of the driving electrode TX will change accordingly according to the voltage amplitude of the voltage scanning signal, so that the mutual capacitance charge storage amount between the driving electrode TX and the corresponding sensing electrode RX will change regularly; optionally, the operating parameter of the driving electrode TX includes the charge storage amount of the driving electrode TX; the sensing electrode RX can sense the change in the operating parameter in the driving electrode TX, and then the operating parameter of the sensing electrode RX itself will also change to generate a response signal; the response signal includes the change in the mutual capacitance between the driving electrode TX and the sensing electrode RX, and the change in the operating parameter of the driving electrode TX can be completely obtained through the response signal, which is beneficial to the mutual capacitance detection circuit 10 for the detection accuracy and detection efficiency of the mutual capacitance between adjacent driving electrodes TX and sensing electrodes RX.

[0088] Optionally, the response signal is a voltage signal or a current signal, and the response signal is used to characterize the change in mutual capacitance between the driving electrode TX and the sensing electrode RX with extremely high accuracy; when the voltage amplitude of the voltage scanning signal changes, the capacitive coupling state between the driving electrode TX and the sensing electrode RX will also change accordingly; therefore, the mutual capacitance information can be accurately obtained through the response signal, the operation is simple, and the mutual capacitance detection steps are relatively simplified.

[0089] The receiving module 103 is connected to the sensing module 102 , and is used to obtain the change in mutual capacitance between the driving electrode TX and the sensing electrode RX according to the response signal.

[0090] The receiving module 103 has a signal analysis and processing function. The sensing module 102 outputs a response signal to the receiving module 103. The receiving module 103 is compatible with identifying and parsing the capacitance information in the response signal. Through the receiving module 103, the actual mutual capacitance fluctuation between the driving electrode TX and the sensing electrode RX can be obtained in real time; therefore, the response signal is an electrical signal, and the response signal maintains a compatible and stable transmission function between the sensing module 102 and the receiving module 103, and the complete mutual capacitance change information can be retained through the response signal to realize a rapid detection function of the mutual capacitance; therefore, the receiving module 103 in this embodiment can obtain the characterization amount of the mutual capacitance according to the actual needs of the technician, and has strong compatibility, improves the internal signal conversion and processing rate of the mutual capacitance detection circuit 10, and realizes high-precision detection and flexible control functions of the mutual capacitance. The mutual capacitance detection circuit 10 has a relatively simplified mutual capacitance detection step and detection cost.

[0091] exist Figure 1In the schematic diagram of the structure of the mutual capacitance detection circuit 10, the mutual capacitance detection circuit 10 has a relatively simplified circuit module structure. The voltage conversion state of the voltage regulation module 101 can be adjusted in real time by using a control signal, and the operation is simple. The voltage scanning signal output by the voltage regulation module 101 has different voltage amplitudes; and then the mutual capacitance charge storage state between the driving electrode TX and the sensing electrode RX can be changed by the voltage scanning signal. The sensing electrode RX senses the change in the operating parameter of the driving electrode TX to output a response signal, and then the response amplitude of the sensing electrode RX has a one-to-one correspondence with the voltage amplitude of the voltage scanning signal. The receiving module 103 The mutual capacitance change information between the driving electrode TX and the sensing electrode RX is accurately obtained according to the response signal to complete the accurate detection function of the mutual capacitance between the driving electrode TX and the sensing electrode RX, and the detection result of the mutual capacitance has high precision and accuracy; therefore, this embodiment can output a voltage scanning signal of any amplitude after voltage regulation by the voltage regulation module 101, and the voltage amplitude of the voltage scanning signal has good controllability and flexibility. The mutual capacitance charge storage amount between the driving electrode TX and the sensing electrode RX can change accordingly under the drive of the voltage scanning signal. By obtaining the response signal generated by the sensing electrode RX, the processing module 103 can completely analyze the mutual capacitance change in the response signal, and the mutual capacitance detection circuit 10 is relatively simple for the mutual capacitance detection process and has a wide range of applications; therefore, in this embodiment, the mutual capacitance detection circuit 10 can flexibly adjust the voltage amplitude of the voltage scanning signal during the mutual capacitance detection process, so that the mutual capacitance between the driving electrode TX and the sensing electrode RX will respond adaptively according to the voltage scanning signal, and the mutual capacitance detection process of the mutual capacitance detection circuit 10 has good adjustability and controllability, and the input voltage of the driving electrode TX during the mutual capacitance detection process has higher ease of operation, which simplifies the circuit module structure of the mutual capacitance detection circuit 10. The circuit modules on the mutual capacitance detection circuit 10 have a more integrated layout, which reduces the detection cost and application cost of the mutual capacitance and has higher compatibility; therefore, the mutual capacitance detection circuit 10 in this embodiment does not need to use additional electronic devices such as voltage stabilizing circuits to adjust the input voltage of the electrode, which effectively solves the problem that the voltage regulation steps in the traditional technology are too complicated, and the voltage regulation range in the mutual capacitance detection process is narrow and the flexibility is low, resulting in a more complicated circuit structure of the mutual capacitance detection circuit, and the design cost and application cost of the circuit are both high. The traditional mutual capacitance detection circuit has a large space volume, which brings great inconvenience to the mutual capacitance detection process.

[0092] As an optional implementation, the receiving module 103 is a single-chip microcomputer or a CPU (Central Processing Unit); therefore, the corresponding response signal can be compatible and identified through the receiving module 103, and the characterization value of the mutual capacitance can be accurately obtained according to the response signal to complete the mutual capacitance detection process; and thus the receiving module 103 has complete signal transmission and signal analysis functions, which improves the application scope of the mutual capacitance detection function of the mutual capacitance detection circuit 10.

[0093] As an optional implementation, Figure 2 The structure of the voltage regulation module 101 provided in this embodiment is shown in FIG. Figure 2 The voltage regulation module 101 includes: a voltage access unit 1011, at least one voltage processing unit 1012 and at least one switch control unit 1013.

[0094] The voltage access unit 1011 accesses N first drive voltages and M first reference voltages. The voltage access unit 1011 is used to be turned on or off according to a first control signal to output a first positive potential signal and M first negative potential signals, and to be turned on or off according to a second control signal to output a second positive potential signal and M second negative potential signals.

[0095] Wherein N is a positive integer greater than 1, M is a positive integer greater than 0, and N=M+1.

[0096] In this embodiment, the input voltage of the voltage regulating module 101 includes N first driving voltages and M first reference voltages.

[0097] The voltage access unit 1011 has the functions of voltage transmission and voltage conversion, so that the voltage access unit 1011 is compatible with various different voltage transmission environments; the first driving voltage includes corresponding voltage driving information, and the first reference voltage includes voltage reference information; optionally, the first driving voltage is generated by the first system power supply, and the first reference voltage is generated by the second system power supply; the first driving voltage and the first reference voltage have a voltage difference of a certain amplitude, and the voltage access unit 1011 has a compatible voltage access function; the voltage regulation module 101 accesses multiple different voltage information to achieve a more flexible power conversion function.

[0098] In this embodiment, the control signal includes a first control signal and a second control signal. Optionally, the phases of the first control signal and the second control signal are staggered, so that when the voltage access unit 1011 is connected to the first control signal or the second control signal, the voltage access unit 1011 is in different voltage transmission states under the drive of the first control signal and the second control signal, and has strong controllability; the first control signal and the second control signal contain different circuit on-off control information, and the on or off state of the voltage access unit 1011 can be changed in combination with the first control signal and the second control signal, so as to switch different input voltages and output corresponding potential signals, thereby improving the voltage transmission accuracy and transmission efficiency of the voltage access unit 1011, so that the mutual capacitance detection circuit 10 performs mutual capacitance detection according to the actual needs of the technician, and has strong controllability; specifically, the voltage access unit 1011 can be made to perform mutual capacitance detection according to the actual needs of the technician through the first control signal. Unit 1011 outputs a first positive potential signal and a first negative potential signal, wherein the first positive potential signal and the first negative potential signal have a specific voltage difference, and the first positive potential signal and the first negative potential signal can be combined to drive the mutual capacitance detection circuit 10 to be in a first working state; the voltage access unit 1011 can output a second positive potential signal and a second negative potential signal through a second control signal, and the mutual capacitance detection circuit 10 can be driven to be in a second working state through the potential difference between the second positive potential signal and the second negative potential signal; therefore, when the voltage access unit 1011 is in different voltage conversion states, the voltage access unit 1011 can output positive potential signals and negative potential signals of different amplitudes to adjust the mutual capacitance detection state of the mutual capacitance detection circuit 10 in real time, and the working state of the voltage access unit 1011 has higher flexibility and reliability, and a wider range of applications.

[0099] Each voltage processing unit 1012 is connected to a logic control signal, and the voltage processing unit 1012 is used to perform potential conversion processing on the logic control signal to obtain a voltage driving signal;

[0100] The logic control signal includes corresponding potential control information. Optionally, the logic control signal is generated by a logic control circuit. The circuit structure of the logic control circuit can be implemented by the circuit structure in the traditional technology, and the logic control signal has different potential states. When the voltage processing unit 1012 is connected to a logic control signal, the voltage processing unit 1012 can change the level state of the logic control signal in real time to generate a corresponding voltage drive signal. Exemplarily, the voltage processing unit 1012 has a potential flipping function. The voltage processing unit 1012 can flip the level state of the logic control signal, and then flexibly and quickly process the potential control information in the logic control signal. The efficiency of the potential conversion is extremely high and the scope of application is extremely wide. The voltage drive signal after the potential conversion includes specific voltage drive information. The voltage drive signal can change the voltage amplitude of the mutual capacitance detection circuit 10 during the mutual capacitance detection process, so that the capacitive coupling state between the electrodes has more flexible controllability and improves the detection accuracy of the mutual capacitance. The voltage regulation module 101 can perform voltage conversion according to the actual needs of the technician to realize the mutual capacitance detection function.

[0101] The switch control unit 1013 is connected to the voltage access unit 1011, and the switch control unit 1013 is connected to the voltage processing unit 1012 in a one-to-one correspondence. The switch control unit 1013 is connected to the drive electrode TX in a one-to-one correspondence. The switch control unit 1013 is used to turn on or off according to the inverted signal of the logic control signal, the first drive voltage and the negative potential signal output by the voltage access unit 1011, so as to convert the voltage drive signal into a voltage scanning signal.

[0102] The negative electrode potential signal output by the voltage access unit 1011 is a first negative electrode potential signal or a second negative electrode potential signal; therefore, when the voltage access unit 1011 is in different signal conversion states, the voltage scanning signal generated by the switch control unit 1013 has different voltage amplitudes;

[0103] Specifically, when the negative electrode potential signal output by the voltage access unit 1011 is a first negative electrode potential signal, the switch control unit 1013 is used to turn on or off according to the inverted signal of the logic control signal, the first drive voltage and the first negative electrode potential signal to convert the voltage drive signal into a voltage scanning signal.

[0104] When the negative potential signal output by the voltage access unit 1011 is the second negative potential signal, the switch control unit 1013 is used to turn on or off according to the inverted signal of the logic control signal, the first drive voltage and the second negative potential signal to convert the voltage drive signal into a voltage scanning signal.

[0105] The switch control unit 1013 and the voltage access unit 1011 can realize the information exchange function, the switch control unit 1013 and the voltage processing unit 1012 can realize the one-to-one communication function, the voltage access unit 1011 outputs the negative electrode potential signal (the first negative electrode potential signal or the second negative electrode potential signal) to the switch control unit 1013, and the voltage processing unit 1012 outputs the voltage drive signal to the switch control unit 1013; wherein the switch control unit 1013 has the on-off control function of the electronic components and the signal form conversion function; specifically, when the voltage access unit 1011 outputs the first negative electrode potential signal The first negative electrode potential signal is output to the switch control unit 1013, and the potential information of the three, the inverted signal of the logic control signal, the first driving voltage and the first negative electrode potential signal, is combined to change the on-off state of the switch control unit 1013. The switch control unit 1013 converts the potential control information in the voltage driving signal in the on state or the off state to obtain a voltage scanning signal, through which the internal power characteristics of the driving electrode TX can be directly changed, and the mutual capacitance charge storage amount between the driving electrode TX and the sensing electrode RX will also change adaptively; when the voltage access unit 1011 changes the second negative electrode potential signal to the second negative electrode potential signal, the voltage access unit 1013 can change the internal power characteristics of the driving electrode TX directly ... The first negative electrode signal is output to the switch control unit 1013. The switch control unit 1013 is turned on or off under the control of the inverted signal of the logic control signal, the first driving voltage and the second negative electrode potential signal, so as to obtain a voltage scanning signal after converting the voltage driving signal. The voltage scanning signal converted by the switch control unit 1013 can directly change the mutual capacitance charge storage amount between the driving electrode TX and the sensing electrode RX to complete the mutual capacitance detection function; therefore, the switch control unit 1013 in this embodiment can realize a flexible signal conversion state under the drive of multiple control information. When the mutual capacitance detection circuit 10 is in different working states, the switch control unit 1013 outputs a voltage scanning signal with different voltage amplitudes. The voltage amplitude of the voltage scanning signal has good controllability and a wide adjustment range. The voltage adjustment of the mutual capacitance detection circuit 10 in mutual capacitance detection is relatively simple, so that the mutual capacitance charge storage amount between the driving electrode TX and the sensing electrode RX changes adaptively, and the application range is extremely wide; the mutual capacitance detection circuit 10 can be driven by the voltage scanning signal to realize a stable mutual capacitance detection state, thereby ensuring the mutual capacitance detection accuracy between the driving electrode TX and the sensing electrode RX.

[0106] As an optional implementation, the first driving voltage, the first reference voltage, the first positive potential signal, the first negative potential signal, the second positive potential signal, the logic control signal and the second negative potential signal satisfy the following relationship:

[0107] VPWR>VGND (1);

[0108] VSSTX1=VGND(2);

[0109] VDDTX1=VPWR(3);

[0110] VSSTX2=(Ni)*VPWR (4);

[0111] VDDTX2 = N*VPWR (5);

[0112] VIN1 = VPWR (6);

[0113] VIN2 = VGND (7);

[0114] In the above formulas (1) to (7), VPWR is the amplitude of the first driving voltage, VGND is the amplitude of the first reference voltage, VSSTX1 is the voltage amplitude of the first negative potential signal, VDDTX1 is the voltage amplitude of the first positive potential signal, VSSTX2 is the voltage amplitude of the second negative potential signal, and VDDTX2 is the voltage amplitude of the second positive potential signal; VIN1 is the high level amplitude of the logic control signal, VIN2 is the low level amplitude of the logic control signal, and i is a positive integer greater than 0 and less than N.

[0115] In this embodiment, there is a specific correlation between the level states of various control signals inside the voltage regulation module 101, and then the voltage regulation module 101 can flexibly adjust the input voltage according to the detection accuracy of the mutual capacitance to obtain a voltage scanning signal with a large voltage amplitude variation range. The voltage scanning signal can directly change the mutual capacitance charge storage state between the driving electrode TX and the sensing electrode RX to ensure the detection accuracy of the mutual capacitance; therefore, after the voltage regulation module 101 adjusts the input voltage according to a specific control signal, a voltage driving signal with different circuit driving functions can be obtained, the signal conversion state of the voltage regulation module 101 has good adjustability and flexibility, and the voltage amplitude of the voltage scanning signal has higher control accuracy and reliability, which brings greater convenience to the mutual capacitance detection process and a wider range of applications.

[0116] As an optional implementation, Figure 3 FIG. 1 shows a schematic diagram of the circuit structure of the voltage access unit 1011 when M=1 provided in this embodiment. Figure 3 The voltage access unit 1011 includes: a first switch tube S1, a second switch tube S2, a third switch tube S3 and a first capacitor C1.

[0117] The first conduction end of the first switch tube S1 is connected to the first driving voltage A1, the control end of the first switch tube S1 is connected to the first control signal E1, the second conduction end of the first switch tube S1 and the first end of the first capacitor C1 are connected together to form the positive output end of the voltage access unit 1011, and the positive output end of the voltage access unit 1011 outputs the first positive potential signal B1 or the second positive potential signal B2; wherein, the positive output end of the voltage access unit 1011 is connected to the switch control unit 1013, when the voltage access unit 1011 generates the first positive potential signal B1 or the second positive potential signal B2, the voltage access unit 1011 outputs the corresponding positive potential signal to the switch control unit 1013 through the positive output end to change the signal conversion state of the switch control unit 1013.

[0118] Specifically, when the control end of the first switch tube S1 is connected to the first control signal, the on or off state of the first switch tube S1 can be changed by the level state of the first control signal, so that the second conduction end of the first switch tube S1 outputs a potential signal of a different amplitude; exemplarily, when the first control signal is in the first level state, the first conduction end and the second conduction end of the first switch tube S1 are connected; when the first control signal is in the second level state, the first conduction end and the second conduction end of the first switch tube S1 are disconnected; thus, the on and off state of the first switch tube S1 has flexible and fast adjustable performance, and the potential signal output by the positive output end of the voltage access unit 1011 has different amplitudes according to the on or off state of the first switch tube S1, so as to dynamically change the voltage amplitude of the voltage scanning signal.

[0119] The second end of the first capacitor C1, the first conduction end of the second switch tube S1 and the first conduction end of the third switch tube S3 are connected together to form the negative output end of the voltage access unit 1011, and the negative output end of the voltage access unit 1011 outputs the first negative potential signal B3 or the second negative potential signal B4; wherein the negative output end of the voltage access unit 1011 is connected to the switch control unit 1013, when the voltage access unit 1011 generates the first negative potential signal B3 or the second negative potential signal B4, the voltage access unit 1011 outputs the first negative potential signal B3 or the second negative potential signal B4 to the switch control unit 1013 to change the on-off state of the switch control unit 1013, and the mutual capacitance detection circuit 10 has a compatible signal transmission function inside.

[0120] The control end of the second switch tube S2 is connected to the first control signal E1.

[0121] The control terminal of the third switch tube S3 is connected to the second control signal E2.

[0122] The second conduction terminal of the second switch tube S2 is connected to the first reference voltage A2.

[0123] The second conduction terminal of the third switch tube S3 is connected to the first driving voltage A1.

[0124] The on or off state of the second switch tube S2 can be changed by the level state of the first control signal E1, so that the first conduction end and the second conduction end of the second switch tube S2 have different voltage transmission states for the first reference voltage A2; the on or off state of the third switch tube S3 can be changed by the level state of the second control signal E2, so that the first conduction end and the second conduction end of the third switch tube S3 have different voltage transmission states for the first driving voltage A1, and the negative output end of the voltage access unit 1011 can output potential signals of different level states according to the on-off state of the second switch tube S2 and the on-off state of the third switch tube S3. The signal conversion state of the voltage access unit 1011 has high controllability and flexibility.

[0125] Optionally, the first switch tube S1 is a triode or a MOS tube, the second switch tube S2 is a triode or a MOS tube, and the third switch tube S3 is a triode or a MOS tube; illustratively, when the first switch tube S1 is a MOS tube, the source of the MOS tube is the first conduction end of the first switch tube S1, the drain of the MOS tube is the second conduction end of the first switch tube S1, and the gate of the MOS tube is the control end of the first switch tube S1; thus, the voltage transmission state of the voltage access unit 1011 has high adjustability.

[0126] exist Figure 3 In the circuit structure of the voltage access unit 1011, the first capacitor C1 can achieve a boosting effect, so that the first positive electrode potential signal B1 and the second positive electrode potential signal B2 output by the voltage access unit 1011 have different level states; specifically, since the control end of the first switch tube S1 and the control end of the second switch tube S2 are commonly connected to the first control signal E1, the first switch tube S1 and the second switch tube S2 have the same on or off state according to the first control signal E1; and the first control signal E1 and the second control signal E2 can respectively control the switch tubes to be in different on or off states, so that the two ends of the first capacitor C1 have different voltage amplitudes, and the voltage access unit 1011 outputs potential signals with different voltage amplitudes.

[0127] For example, in order to better illustrate the working state of the voltage access unit 1011, Figure 4 The working principle of the voltage access unit 1011 is described. Figure 4 The voltage amplitude waveforms of the various control signals in the voltage access unit 1011 shown in this embodiment are provided; specifically, they are as follows:

[0128] In this embodiment, the high level state of the first control signal E1 means: the voltage amplitude of the first control signal E1 is equal to the amplitude of the first driving voltage; the low level state of the first control signal E1 means: the voltage amplitude of the first control signal E1 is equal to the amplitude of the first reference voltage; the high level state of the second control signal E2 means: the voltage amplitude of the second control signal E2 is equal to the amplitude of the first driving voltage; the low level state of the second control signal E2 means: the voltage amplitude of the first control signal E1 is equal to the amplitude of the first reference voltage; therefore, the on-off state of each switch tube can be changed by combining the high and low level changes of the first control signal E1 and the high and low level changes of the second control signal E2, with high flexibility.

[0129] When the first control signal E1 is in a high level state, the first control signal E1 is used to turn on the first switch tube S1 and the second switch tube S2, and the third switch tube S3 is turned off, the positive output end of the voltage access unit 1011 outputs the first positive potential signal B1, and the negative output end of the voltage access unit 1011 outputs the first negative potential signal B3. At this time, the positive output end of the voltage access unit 1011 is connected to the first driving voltage through the first switch tube S1, and the negative output end of the voltage access unit 1011 is connected to the second reference voltage through the second switch tube S2; then the voltage amplitude of the first positive potential signal B1 is equal to the amplitude of the first driving voltage, and the voltage amplitude of the first negative potential signal B3 is equal to the amplitude of the first reference voltage, which can be expressed as follows:

[0130] VSSTX1=VGND(8)

[0131] VDDTX1=VPWR(9)

[0132] When the first control signal E1 changes from a high level state to a low level state, and the level state of the second control signal E2 is a high level state, the first switch tube S1 and the second switch tube S2 are both disconnected, and the third switch tube S3 is turned on by the second control signal E2, and the positive output end of the voltage access unit 1011 outputs the second positive potential signal B2, and the negative output end of the voltage access unit 1011 outputs the second negative potential signal B4; the negative output end of the voltage access unit 1011 is connected to the first driving voltage through the third switch tube S3, and through the boosting effect of the first capacitor C1, after the third switch tube S3 is turned on, the voltage amplitude of the first end of the first capacitor C1 is twice the amplitude of the first driving voltage; then the voltage amplitude of the second positive potential signal B2 and the voltage amplitude of the second negative potential signal B4 satisfy the following relationship:

[0133] VSSTX2=VPWR (10)

[0134] VDDTX2=2*VPWR (11)

[0135] It should be noted that the above formulas (8) to (11) can refer to the above formulas (1) to (5); therefore, the on or off state of each switch tube can be changed by the level state of the first control signal E1 and the level state of the second control signal E2, so that the voltage access unit 1011 outputs different potential signals, and the first positive potential signal B1 and the second positive potential signal B2 have different voltage amplitudes to change the mutual capacitance detection function of the mutual capacitance detection circuit 10, so that the amplitude of the voltage scanning signal has a simpler adjustability.

[0136] As an optional implementation, Figure 5 The circuit structure of the switch control unit 1013 provided in this embodiment is shown in FIG. Figure 5 The switch control unit 1013 includes: a fourth switch tube S4, a fifth switch tube S5 and a sixth switch tube S6.

[0137] The first conduction end of the fourth switch tube S4 is connected to the voltage processing unit 1012, and the voltage processing unit 1012 outputs the voltage driving signal to the first conduction end of the fourth switch tube S4. The control end of the fourth switch tube S4 is connected to the first negative electrode potential signal B3 or the second negative electrode potential signal B4. The second conduction end of the fourth switch tube S4 and the first conduction end of the fifth switch tube S5 are connected together to form a signal output end of the switch control unit 1013. The signal output end of the switch control unit 1013 is used to output a voltage scanning signal; wherein the fourth switch tube S4 has a voltage clamping function, and the signal output end of the switch control unit 1013 is connected to the driving electrode TX, and then when the voltage scanning signal has different voltage amplitudes, the operating parameters of the driving electrode TX can be changed through the voltage scanning signal, so that the mutual capacitance charge storage amount between the driving electrode TX and the sensing electrode RX changes accordingly, thereby improving the control response accuracy of the sensing module 102.

[0138] The control terminal of the fifth switch tube S5 is connected to the first driving voltage A1.

[0139] The second conduction terminal of the fifth switch tube S5 is connected to the first conduction terminal of the sixth switch tube S6; the second conduction terminal of the sixth switch tube S6 is connected to the first reference voltage A2, wherein the fifth switch tube S5 has a voltage clamping function, so that the signal output terminal of the switch control unit 1013 can output a voltage scanning signal with a stable amplitude; the fifth switch tube S5 is in a conducting state, if the sixth switch tube S6 is turned off, the voltage at the second conduction terminal of the fifth switch tube S5 is within a safe range, then the level amplitude of the first conduction terminal of the sixth switch tube S6 is low, and the fifth switch tube S5 can prevent the voltage difference between the first conduction terminal of the sixth switch tube S6 and the second conduction terminal of the sixth switch tube S6 from being too large; the control terminal of the sixth switch tube S6 is connected to the inverted signal of the logic control signal; the on or off state of the sixth switch tube S6 can be changed by the level state of the inverted signal of the logic control signal, so that different voltage transmission states can be achieved between the first conduction terminal and the second conduction terminal of the sixth switch tube S6.

[0140] Optionally, the fourth switch tube S4 is a triode or a MOS tube, the fifth switch tube S5 is a triode or a MOS tube, and the sixth switch tube S6 is a triode or a MOS tube; exemplarily, the fourth switch tube S4 is a PMOS tube, the fifth switch tube S5 is an NMOS tube, and the sixth switch tube S6 is an NMOS tube; the on or off state of each MOS tube can be changed by combining the first negative electrode potential signal B3, the second negative electrode potential signal B4, the first drive voltage A1 and the inverted signal of the logic control signal, so that the electronic components in the switch control unit 1013 can realize different voltage conversion functions, the voltage scanning signal has different voltage amplitudes, and the control is flexible.

[0141] Specifically, by changing the on-off state of the sixth switch tube S6, a short circuit between the voltage driving signal and the first reference voltage A2 can be avoided, so that the voltage amplitude of the voltage scanning signal has a safer adjustability; when the first conduction end and the second conduction end of the fifth switch tube S5 are connected, the potential clamping function of the first conduction end and the second conduction end of the sixth switch tube S6 can be realized to prevent the voltage difference between the first conduction end and the second conduction end of the sixth switch tube S6 from being too large when the voltage scanning signal is at a high potential; therefore, the switch control unit in this embodiment can output a more stable voltage scanning signal and avoid using high-voltage resistant devices; the switch control unit can perform a safe conversion function for the voltage driving signal, and the voltage amplitude of the voltage scanning signal has a more convenient adjustment performance.

[0142] As an optional implementation, Figure 6 FIG. 1 shows a schematic diagram of the circuit structure of the voltage access unit 1011 when M>1 provided in this embodiment. Figure 6The voltage access unit 1011 includes: a seventh switch tube S7, an eighth switch tube S8, a ninth switch tube S9, a second capacitor C2 and a switch array 601;

[0143] The first conduction end of the seventh switch tube S7 is connected to the first driving voltage A1, the control end of the seventh switch tube S7 is connected to the first control signal E1, the second conduction end of the seventh switch tube S7 and the first end of the second capacitor C2 are connected together to form the positive output end of the voltage access unit 1011, and the positive output end of the voltage access unit 1011 outputs a first positive potential signal or a second positive potential signal; wherein the positive output end of the voltage access unit 1011 is connected to the switch control unit 1013, and the potential signal output by the positive output end of the voltage access unit 1011 can make the switch control unit 1013 in different working states.

[0144] A first conduction terminal of the eighth switch tube S8 is connected to the first reference voltage A2 , and a control terminal of the eighth switch tube S8 is connected to the first control signal E1 .

[0145] The first conduction terminal of the ninth switch tube S9 is connected to the first driving voltage A1 , and the control terminal of the ninth switch tube S9 is connected to the second control signal E2 .

[0146] The switch array 601 includes M-1 switch driving units, the voltage input terminal of the previous switch driving unit is connected to the voltage output terminal of the next switch driving unit, the voltage output terminal of the first switch driving unit is connected to the second end of the second capacitor C2, and the voltage input terminal of the last switch driving unit is connected to the second conduction terminal of the eighth switch tube S8 and the second conduction terminal of the ninth switch tube S9.

[0147] The voltage output end of the first switch driving unit is used to output a first negative potential signal or a second negative potential signal; the voltage input end of each switch driving unit outputs a first negative potential signal or a second negative potential signal; the voltage output end of the first switch driving unit and the voltage input end of each switch driving unit are connected to the switch control unit 1013, and then the signal transmission state of the switch control unit 1013 is changed through the negative potential signal.

[0148] Each switch driving unit includes: a tenth switch tube S10, an eleventh switch tube S11, a twelfth switch tube S12 and a third capacitor C3.

[0149] The first conduction end of the tenth switch tube S10 is connected to the first reference voltage A2, the control end of the tenth switch tube S10 is connected to the first control signal E1, the second conduction end of the tenth switch tube S10 and the first conduction end of the eleventh switch tube S11 are connected together to form a voltage output end of the switch driving unit, the control end of the eleventh switch tube S11 is connected to the second control signal E2, the second conduction end of the eleventh switch tube S11 and the first conduction end of the twelfth switch tube S12 are connected together to the first end of the third capacitor C3, the control end of the twelfth switch tube S12 is connected to the first control signal E1, and the second conduction end of the twelfth switch tube S12 is connected to the first driving voltage A1; the second end of the third capacitor C3 is the voltage input end of the switch driving unit.

[0150] It should be noted that Figure 6 The circuit form of the medium voltage access unit 1011 is: Figure 3 The circuit structure of the medium voltage access unit 1011 is expanded, so Figure 6 The working mode of the internal electronic components of the medium voltage access unit 1011 can be referred to Figure 3 A specific embodiment of the invention; wherein Figure 6 The voltage access unit 1011 and Figure 3 The difference of the medium voltage access unit 1011 is: Figure 6 The medium voltage access unit 1011 also includes multiple switch driving units. When the first control signal E1 and the second control signal E2 are used to control each switch tube in the voltage access unit 1011 to be turned on or off, the boosting effect of the third capacitor C3 in each switch driving unit is utilized, and the first positive potential signal B1 and the second positive potential signal B2 outputted from the positive output end of the voltage access unit 1011 have a larger voltage amplitude difference, and the voltage amplitude of the positive potential signal can be increased to M+1 times the first driving voltage, and the voltage input end of the switch driving unit can output multiple first negative potential signals or multiple second negative potential signals. The potential signal output by the voltage access unit 1011 has higher adjustment flexibility, thereby improving the voltage amplitude control accuracy of the voltage scanning signal.

[0151] As an optional implementation, Figure 7 Another circuit structure of the switch control unit 1013 provided in this embodiment is shown. Figure 7 The switch control unit 1013 includes: a thirteenth switch tube S13, a fourteenth switch tube S14 and a voltage clamping unit 701.

[0152] The first conduction end of the thirteenth switch tube S13 is connected to the first reference voltage A2, the control end of the thirteenth switch tube S13 is connected to the inverted signal of the logic control signal, the second conduction end of the thirteenth switch tube S13 is connected to the first conduction end of the fourteenth switch tube S14, and the control end of the fourteenth switch tube S14 is connected to the first driving voltage A1.

[0153] The voltage clamping unit 701 includes a first voltage processor 7011 and a second voltage processor 7012 . The first voltage processor 7011 includes M fifteenth switch tubes S5 , and the second voltage processor includes M−1 sixteenth switch tubes S16 .

[0154] In the first voltage processor 7011, the first conduction terminal of the first fifteenth switch tube S15 is connected to the voltage processing unit 1012, the second conduction terminal of the last fifteenth switch tube S15 is connected to the drive electrode TX, the second conduction terminal of the previous fifteenth switch tube S15 is connected to the first conduction terminal of the next fifteenth switch tube S15, the control terminal of the first fifteenth switch tube S15 is connected to the first negative electrode potential signal B3 or the second negative electrode potential signal B4 output by the first switch driving unit, the second fifteenth switch tube S15 is connected to the first negative electrode potential signal B3 or the second negative electrode potential signal B4 output by the second switch driving unit, and so on.

[0155] In this embodiment, the first voltage processor 7011 uses multiple cascaded fifteenth switch tubes S15 to conduct voltage drive signals. The signal conversion state of the switch control unit 1013 has a more flexible control method. The operating state of the driving electrode TX can be changed at any time through the voltage scanning signal, and the application range is wider.

[0156] In the second voltage processor 7012, the first conduction end of the first sixteenth switch tube S16 is connected to the driving electrode TX, the second conduction end of the last sixteenth switch tube S16 is connected to the second conduction end of the fourteenth switch tube S14, the second conduction end of the previous sixteenth switch tube S16 is connected to the first conduction end of the next sixteenth switch tube S16, and the control end of each sixteenth switch tube S16 is connected to the negative control voltage; wherein the negative control voltage is the voltage of the first end of the third capacitor C3 in each switch driving unit; and then when the switch driving unit is turned on or off, the sixteenth switch tube S1 can be turned on or off according to the boost state of the third capacitor C3, so as to improve the control accuracy of the signal conversion process of the second voltage processor 7012, and the switch control unit 1013 can output voltage scanning signals with different voltage amplitudes, and the mutual capacitance detection circuit 10 has higher ease of operation.

[0157] It should be noted that Figure 7 The circuit structure of the switch control unit 1013 is shown as follows: Figure 5The circuit structure of the switch control unit 1013 is expanded, so Figure 7 The working principle of the switch control unit 1013 can be referred to Figure 5 embodiments; and Figure 7 The switch control unit 1013 and Figure 5 The difference between the switch control unit 1013 in FIG. 1 is that: Figure 7 The switch control unit 1013 also includes a voltage clamping unit 701, and the voltage conversion state of the voltage clamping unit 701 can be changed according to multiple negative electrode potential signals. The voltage amplitude of the voltage scanning signal has higher adjustability and flexibility, thereby improving the mutual capacitance detection accuracy of the mutual capacitance detection circuit 10.

[0158] As an optional implementation, Figure 8 The circuit structure of the voltage processing unit 1012 provided in this embodiment is shown in FIG. Figure 8 The voltage processing unit 1012 includes: a potential converter 801, a first inverter INV1 and a second inverter INV2.

[0159] The signal input terminal of the potential converter 801 is connected to the logic control signal IN, and the potential converter 801 is used to adjust the level amplitude of the logic control signal IN.

[0160] Among them, the circuit structure of the potential converter 801 can be implemented by using the circuit structure in the conventional technology. After the potential converter 801 adjusts the level state of the logic control signal IN, the potential converter 801 can output signals with different voltage amplitudes. For example, the potential converter 801 can increase the voltage amplitude of the logic control signal IN. Combined with the above formulas (1) to (7), when the high level amplitude of the logic control signal IN is VPWR, the high level amplitude output by the potential converter 801 is 2*VPWR; when the low level amplitude of the logic control signal IN is VGND, the low level amplitude output by the potential converter 801 is VPWR, and the operation is simple.

[0161] The input end of the first inverter INV1 is connected to the signal output end of the potential converter 801; the input end of the second inverter INV2 is connected to the output end of the first inverter INV1, and the output end of the second inverter INV2 is connected to the switch control unit 1013; and then the voltage drive signal is output to the switch control unit 1013 through the output end of the second inverter INV2 to change the signal conversion state of the switch control unit 1013.

[0162] In this embodiment, since the logic control signal IN has different level states, for example, the logic control signal IN is in a high level state or a low level state, after the voltage of the logic control signal IN is adjusted by the potential converter 801, and after the first inverter INV1 and the second inverter INV2 sequentially perform phase conversion and drive control on the logic control signal IN, the voltage drive signal has different voltage amplitudes to change the signal conversion state of the switch control unit 1013, and the voltage drive information of the voltage drive signal has more flexible controllability.

[0163] As an optional implementation, Fig. 9 Another circuit structure of the voltage processing unit 1012 provided in this embodiment is shown. Fig. 9 The voltage processing unit 1012 includes: a seventeenth switch tube S17, an eighteenth switch tube S18, an OR gate OR, a third inverter INV3, a fourth inverter INV4 and a fifth inverter INV5.

[0164] A first input terminal of the OR gate OR is connected to the logic control signal IN, a second input terminal of the OR gate OR is connected to the second control signal E2, an output terminal of the OR gate OR is connected to the first conduction terminal of the seventeenth switch tube S17, a second conduction terminal of the seventeenth switch tube S17 and a first conduction terminal of the eighteenth switch tube S18 are commonly connected to the input terminal of the third inverter INV3, a second conduction terminal of the eighteenth switch tube S18 is connected to the output terminal of the fourth inverter INV4, an output terminal of the third inverter INV3 and an input terminal of the fourth inverter INV4 are commonly connected to the input terminal of the fifth inverter INV5, an output terminal of the fifth inverter INV5 is connected to the switch control unit 1013; a voltage drive signal is output to the switch control unit 1013 through the output terminal of the fifth inverter INV5, so that the switch control unit 1013 realizes different signal conversion states.

[0165] The control end of the seventeenth switch tube S17 is connected to the third control signal, and the control end of the eighteenth switch tube S17 is connected to the fourth control signal; wherein the fourth control signal is an inverted signal of the third control signal, and the voltage amplitude of the third control signal is the same as the first driving voltage.

[0166] exist Fig. 9FIG. 1 shows the circuit structure of the voltage processing unit 1012. The third inverter INV3, the fourth inverter INV4 and the eighteenth switch tube S18 can realize the signal latching function, so that the voltage processing unit 1012 can latch the level state of the input logic control signal IN, avoiding the influence of the "OR" logic processing in the OR gate OR, and the voltage amplitude of the voltage driving signal has a higher adjustment accuracy. After the logic control signal IN and the second control signal E2 are processed by the OR gate OR, the voltage processing unit 1012 and the voltage access unit 101 1 can realize synchronous processing of voltage information, and ensure the signal conversion accuracy of the switch control unit 1013; wherein the seventeenth switch tube S17 and the eighteenth switch tube S18 realize different on or off states in response to the third control signal S3 and the fourth control signal S4, and then after reverse conversion by the inverter, the on and off states of the seventeenth switch tube S17 and the eighteenth switch tube S18 can realize the signal latching function for the voltage scanning signal, and the voltage processing unit 1012 has good controllability, which is conducive to simplifying the voltage adjustment steps in the mutual capacitance detection process.

[0167] Fig.10 The structure of the mutual capacitance detection system 100 with voltage regulation function provided by this embodiment is shown. Fig.10 The mutual capacitance detection system 100 includes the mutual capacitance detection circuit 10 and the power module 1001 as described above; the power module 1001 is connected to the mutual capacitance detection circuit 10, and the power module 1001 is used to supply power to the mutual capacitance detection circuit 10; the power supply safety of the mutual capacitance detection circuit 10 is guaranteed by the power module 1001, so that the mutual capacitance detection circuit can stably and reliably obtain the mutual capacitance change, thereby improving the application scope and reliability of the mutual capacitance detection circuit 10.

[0168] Optionally, the power module 1001 is a DC power supply, and the DC power output by the DC power supply can maintain the working stability and safety of each electronic component in the mutual capacitance detection circuit 10.

[0169] Reference Figures 1 to 9In the embodiment of the invention, the mutual capacitance detection circuit 10 can change the voltage amplitude of the voltage scanning signal. Under the drive of the voltage scanning signal, the charge storage amount between the driving electrode TX and the sensing electrode RX will change accordingly. The change amount of the mutual capacitance can be accurately obtained according to the response amount of the sensing electrode RX, and the detection result has high accuracy and credibility. Therefore, the mutual capacitance detection circuit 10 has a relatively simple voltage adjustment method, and the voltage amplitude in the mutual capacitance detection process can be adjusted arbitrarily, which is easy to operate, and the voltage difference is greater. The mutual capacitance detection process between the driving electrode TX and the sensing electrode RX is more flexible, which simplifies the circuit structure of the mutual capacitance detection circuit 10, and further reduces the mutual capacitance detection. cost; therefore, this embodiment applies the mutual capacitance detection circuit 10 to the mutual capacitance detection system 100, through which the mutual capacitance detection system 100 can realize the precise detection function of the mutual capacitance, and has strong controllability, which will play a positive role in promoting the widespread application of the mutual capacitance detection technology in this field and generate important production value; it effectively solves the problem that the mutual capacitance detection system in the traditional technology needs to adopt additional auxiliary voltage stabilizing devices to complete the mutual capacitance detection process, and the flexibility and controllability of the mutual capacitance detection process are low, which leads to a more complex internal circuit structure of the mutual capacitance detection system, a larger circuit space volume, and a higher circuit design cost and application cost, which brings great inconvenience to the use of technical personnel.

[0170] Various embodiments are described herein for various devices, circuits, apparatuses, systems and / or methods. Many specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture and use of the embodiments as described in the specification and shown in the drawings. However, those skilled in the art will appreciate that the embodiments may be implemented without such specific details. In other examples, well-known operations, parts and elements are described in detail so as not to make the embodiments in the specification difficult to understand. Those skilled in the art will appreciate that the embodiments herein and shown are non-limiting examples, and therefore it will be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments.

[0171] References to "various embodiments", "in an embodiment", "one embodiment", or "an embodiment" throughout the specification, etc., mean that a particular feature, structure, or characteristic described with respect to an embodiment is included in at least one embodiment. Therefore, the appearance of the phrases "in various embodiments", "in some embodiments", "in an embodiment", or "in an embodiment", etc., in appropriate places throughout the specification, do not necessarily refer to the same embodiment. In addition, particular features, structures, or characteristics may be combined in any appropriate manner in one or more embodiments. Therefore, a particular feature, structure, or characteristic shown or described with respect to one embodiment may be combined in whole or in part with features, structures, or characteristics of one or more other embodiments without assuming that such a combination is not an illogical or non-functional limitation. Any directional references (e.g., plus, minus, upper, lower, up, down, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are used for identification purposes to help the reader understand the present disclosure, and do not create limitations, particularly with respect to the location, orientation, or use of the embodiments.

[0172] Although certain embodiments are described above with a certain degree of detail, those skilled in the art may make many changes to the disclosed embodiments without departing from the scope of the present disclosure. Connection references (e.g., attachment, coupling, connection, etc.) should be interpreted broadly and may include intermediate members between the connection of elements and relative motion between elements. Therefore, connection references do not necessarily imply that two elements are directly connected / coupled and are in a fixed relationship with each other. The use of "for example" throughout the specification should be interpreted broadly and used to provide non-limiting examples of embodiments of the present disclosure, and the present disclosure is not limited to such examples. It is intended that all matters included in the above description or shown in the accompanying drawings should be interpreted as merely illustrative rather than restrictive. Changes in details or structure may be made without departing from the present disclosure.

[0173] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A mutual capacitance detection circuit with voltage regulation function, characterized in that: include: A voltage regulating module, used for regulating the input voltage according to the received control signal and then outputting a voltage scanning signal; a sensing module connected to the voltage regulating module, the sensing module being used to output a response signal according to the voltage scanning signal; the sensing module comprising at least one sensing electrode and driving electrodes having the same number as the sensing electrodes, the sensing electrodes being arranged in a one-to-one correspondence with the driving electrodes, the driving electrodes being used to receive and transmit the voltage scanning signal so that the sensing electrodes generate the response signal, the response signal being in response to a change in an operating parameter of the driving electrode driven by the voltage scanning signal; as well as a receiving module connected to the sensing module, the receiving module being used to obtain a change in mutual capacitance between the driving electrode and the sensing electrode according to the response signal; The voltage regulation module comprises: a voltage access unit, accessing N first drive voltages and M first reference voltages, the voltage access unit being used to conduct or shut down according to a first control signal to output a first positive potential signal and M first negative potential signals, and to conduct or shut down according to a second control signal to output a second positive potential signal and M second negative potential signals, wherein the first control signal and the second control signal contain different circuit on-off control information; At least one voltage processing unit, each of which is connected to a logic control signal, and is used to perform potential conversion processing on the logic control signal to obtain a voltage driving signal; and At least one switch control unit, the switch control unit is connected to the voltage access unit, and the switch control unit is connected to the voltage processing unit in a one-to-one correspondence, the switch control unit is connected to the drive electrode in a one-to-one correspondence, and the switch control unit is used to turn on or off according to the inverted signal of the logic control signal, the first drive voltage and the negative potential signal output by the voltage access unit, so as to convert the voltage drive signal into the voltage scanning signal; The negative electrode potential signal output by the voltage access unit is the first negative electrode potential signal or the second negative electrode potential signal, N is a positive integer greater than 1, M is a positive integer greater than 0, and N=M+1.

2. The mutual capacitance detection circuit according to claim 1, characterized in that: The first driving voltage, the first reference voltage, the first positive electrode potential signal, the first negative electrode potential signal, the second positive electrode potential signal, the logic control signal and the second negative electrode potential signal satisfy the following relationship: VPWR>VGND; VSSTX1 = VGND; VDDTX1 = VPWR; VSSTX2= (Ni)*VPWR; VDDTX2=N*VPWR; VIN1=VPWR; VIN2 = VGND; In the above formula, VPWR is the amplitude of the first driving voltage, VGND is the amplitude of the first reference voltage, VSSTX1 is the voltage amplitude of the first negative potential signal, VDDTX1 is the voltage amplitude of the first positive potential signal, VSSTX2 is the voltage amplitude of the second negative potential signal, and VDDTX2 is the voltage amplitude of the second positive potential signal; VIN1 is the high level amplitude of the logic control signal, VIN2 is the low level amplitude of the logic control signal, and i is a positive integer greater than 0 and less than N.

3. The mutual capacitance detection circuit according to claim 1, characterized in that: When M=1, the voltage access unit includes: A first switch tube, a second switch tube, a third switch tube and a first capacitor; The first conducting end of the first switch tube is connected to the first driving voltage, the control end of the first switch tube is connected to the first control signal, the second conducting end of the first switch tube and the first end of the first capacitor are connected together to form the positive output end of the voltage access unit, and the positive output end of the voltage access unit outputs the first positive potential signal or the second positive potential signal; The second end of the first capacitor, the first conduction end of the second switch tube, and the first conduction end of the third switch tube are connected together to form a negative output end of the voltage access unit, and the negative output end of the voltage access unit outputs the first negative potential signal or the second negative potential signal; The control end of the second switch tube is connected to the first control signal; The control terminal of the third switch tube is connected to the second control signal; The second conduction end of the second switch tube is connected to the first reference voltage; The second conduction end of the third switch tube is connected to the first driving voltage.

4. The mutual capacitance detection circuit according to claim 3, characterized in that: The switch control unit comprises: a fourth switch tube, a fifth switch tube and a sixth switch tube; The first conduction terminal of the fourth switch tube is connected to the voltage processing unit, the control terminal of the fourth switch tube is connected to the first negative electrode potential signal or the second negative electrode potential signal, the second conduction terminal of the fourth switch tube and the first conduction terminal of the fifth switch tube are connected together to form a signal output terminal of the switch control unit, and the signal output terminal of the switch control unit is used to output the voltage scanning signal; The control terminal of the fifth switch tube is connected to the first driving voltage; The second conduction terminal of the fifth switch tube is connected to the first conduction terminal of the sixth switch tube; The second conduction terminal of the sixth switch tube is connected to the first reference voltage, and the control terminal of the sixth switch tube is connected to the inverted signal of the logic control signal.

5. The mutual capacitance detection circuit according to claim 1, characterized in that: When M>1, the voltage access unit includes: A seventh switch tube, an eighth switch tube, a ninth switch tube, a second capacitor and a switch array; The first conduction end of the seventh switch tube is connected to the first driving voltage, the control end of the seventh switch tube is connected to the first control signal, the second conduction end of the seventh switch tube and the first end of the second capacitor are connected together to form the positive output end of the voltage access unit, and the positive output end of the voltage access unit outputs the first positive potential signal or the second positive potential signal; The first conduction terminal of the eighth switch tube is connected to the first reference voltage, and the control terminal of the eighth switch tube is connected to the first control signal; The first conduction terminal of the ninth switch tube is connected to the first driving voltage, and the control terminal of the ninth switch tube is connected to the second control signal; The switch array includes M-1 switch drive units, a voltage input terminal of a preceding switch drive unit is connected to a voltage output terminal of a succeeding switch drive unit, a voltage output terminal of the first switch drive unit is connected to a second terminal of the second capacitor, and a voltage input terminal of the last switch drive unit is connected to a second conduction terminal of the eighth switch tube and a second conduction terminal of the ninth switch tube; The voltage output end of the first switch driving unit is used to output one of the first negative electrode potential signals or one of the second negative electrode potential signals; the voltage input end of each switch driving unit outputs one of the first negative electrode potential signals or one of the second negative electrode potential signals; Each of the switch driving units includes: a tenth switch tube, an eleventh switch tube, a twelfth switch tube and a third capacitor; The first conduction end of the tenth switch tube is connected to the first reference voltage, the control end of the tenth switch tube is connected to the first control signal, the second conduction end of the tenth switch tube and the first conduction end of the eleventh switch tube are connected together to form the voltage output end of the switch driving unit, the control end of the eleventh switch tube is connected to the second control signal, the second conduction end of the eleventh switch tube and the first conduction end of the twelfth switch tube are connected together to the first end of the third capacitor, the control end of the twelfth switch tube is connected to the first control signal, and the second conduction end of the twelfth switch tube is connected to the first driving voltage; the second end of the third capacitor is the voltage input end of the switch driving unit.

6. The mutual capacitance detection circuit according to claim 5, characterized in that: The switch control unit comprises: A thirteenth switch tube, a fourteenth switch tube and a voltage clamping unit; The first conduction end of the thirteenth switch tube is connected to the first reference voltage, the control end of the thirteenth switch tube is connected to the inverted signal of the logic control signal, the second conduction end of the thirteenth switch tube is connected to the first conduction end of the fourteenth switch tube, and the control end of the fourteenth switch tube is connected to the first driving voltage; The voltage clamping unit includes a first voltage processor and a second voltage processor, the first voltage processor includes M fifteenth switch tubes, and the second voltage processor includes M-1 sixteenth switch tubes; In the first voltage processor, the first conductive end of the first fifteenth switch tube is connected to the voltage processing unit, the second conductive end of the last fifteenth switch tube is connected to the driving electrode, the second conductive end of the first fifteenth switch tube is connected to the first conductive end of the next fifteenth switch tube, and the control end of each fifteenth switch tube is connected to a first negative electrode potential signal or a second negative electrode potential signal; In the second voltage processor, the first conductive end of the first sixteenth switch tube is connected to the driving electrode, the second conductive end of the last sixteenth switch tube is connected to the second conductive end of the fourteenth switch tube, the second conductive end of the first sixteenth switch tube is connected to the first conductive end of the next sixteenth switch tube, and the control end of each sixteenth switch tube is connected to the negative control voltage; The negative electrode control voltage is the voltage of the first end of the third capacitor in each of the switch driving units.

7. The mutual capacitance detection circuit according to claim 1, characterized in that: The voltage processing unit comprises: A potential converter, wherein a signal input terminal of the potential converter is connected to the logic control signal, and the potential converter is used to adjust the level amplitude of the logic control signal; A first inverter, wherein an input terminal of the first inverter is connected to a signal output terminal of the potential converter; and A second inverter, wherein an input terminal of the second inverter is connected to an output terminal of the first inverter, and an output terminal of the second inverter is connected to the switch control unit.

8. The mutual capacitance detection circuit according to claim 1, characterized in that: The voltage processing unit comprises: A seventeenth switch tube, an eighteenth switch tube, an OR gate, a third inverter, a fourth inverter and a fifth inverter; The first input end of the OR gate is connected to the logic control signal, the second input end of the OR gate is connected to the second control signal, the output end of the OR gate is connected to the first conduction end of the seventeenth switch tube, the second conduction end of the seventeenth switch tube and the first conduction end of the eighteenth switch tube are commonly connected to the input end of the third inverter, the second conduction end of the eighteenth switch tube is connected to the output end of the fourth inverter, the output end of the third inverter and the input end of the fourth inverter are commonly connected to the input end of the fifth inverter, and the output end of the fifth inverter is connected to the switch control unit; The control end of the seventeenth switch tube is connected to the third control signal, and the control end of the eighteenth switch tube is connected to the fourth control signal; The fourth control signal is an inverted signal of the third control signal, and the voltage amplitude of the third control signal is the same as the first driving voltage.

9. A mutual capacitance detection system with voltage regulation function, characterized in that: include: The mutual capacitance detection circuit according to any one of claims 1 to 8; and A power module is connected to the mutual capacitance detection circuit, and the power module is used to supply power to the mutual capacitance detection circuit.

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