A multi-touch circuit based on capacitive sensing

Abstract

The utility model discloses a kind of multi-point touch circuit based on capacitance induction, including induction module, main control module and communication module;Induction module includes excitation unit and sampling unit, generates induction signal based on the capacitance change between excitation unit and sampling unit;Wherein, excitation unit at least includes 7 excitation ends, and sampling unit at least includes 7 sampling ends;Main control module generates control signal based on induction signal;Communication module is communicated to controlled equipment by control signal transmission.To multiple excitation ends and sampling ends in induction module constitute mutual-capacitance touch detection system, realize range touch detection, effectively eliminate touch blind area, and can be used to touch seat standard positioning.

Description

Technical Field

[0001] This utility model relates to the field of circuit design technology, and in particular to a multi-touch circuit based on capacitive sensing. Background Technology

[0002] Most existing touch-sensitive panels employ a self-capacitive touch detection principle. This principle uses a pin to measure the capacitance between the pin and ground. Since a human hand acts as a parasitic capacitor, the measured capacitance changes when a hand approaches or touches the surface. This change allows for the determination of whether a touch has occurred, thus initiating the appropriate control action. However, the self-capacitive touch detection principle relies on a touch sensor pad, whose position is typically fixed after assembly. This limits single-point touch detection to specific locations, resulting in a large blind spot and making it less convenient than traditional control buttons. Utility Model Content

[0003] This embodiment discloses a multi-touch circuit based on capacitive sensing, specifically including: Sensing module, main control module, and communication module; The sensing module includes an excitation unit and a sampling unit, and generates a sensing signal based on the capacitance change between the excitation unit and the sampling unit; The excitation unit includes at least 7 excitation terminals, and the sampling unit includes at least 7 sampling terminals; The main control module generates control signals based on the sensing signals; The communication module transmits the control signals to the controlled device.

[0004] As an optional implementation, the excitation unit includes inductor L1, inductor LF1 and voltage regulator U1; The sampling unit includes an inductor 2L-CMC, a transient suppression diode D1, and a serial communication chip U5; The sampling unit samples the capacitance value between itself and the excitation unit to generate the inductive signal.

[0005] As an optional implementation, one end of the inductor L1 is energized, and the other end is connected to the first and third pins of the inductor LF1; The second pin of the inductor LF1 is grounded, and the fourth pin is connected to the first pin of the voltage regulator U1.

[0006] As an optional implementation, the second pin of the inductor 2L-CMC is connected to the first pin of the transient suppression diode D1, and the fourth pin of the inductor 2L-CMC is connected to the second pin of the transient suppression diode D1; The first pin of the transient suppression diode D1 is connected to the seventh pin of the serial communication chip U5, and the third pin of the transient suppression diode D1 is connected to the sixth pin of the serial communication chip U5, so as to output the generated sensing signal to the main control module.

[0007] As an optional implementation, the main control module uses a main control chip U3, with its 25th pin connected to the 1st pin of the serial communication chip U5, its 23rd pin connected to the 3rd pin of the serial communication chip U5, and its 26th pin connected to the 4th pin of the serial communication chip U5, for receiving the sensing signal.

[0008] As an optional implementation, pins 14, 15, and 16 of the main control chip U3 are used to connect to the LED beads and perform lighting control on the LED beads.

[0009] As an optional implementation, pin 3 of the main control chip U3 is used for drive control, and pin 8 is used for triggering a restart.

[0010] As an optional implementation, the communication module uses an RF chip U4, with its first pin connected to the 32nd pin of the main control chip U3, its second pin connected to the 31st pin of the main control chip U3, its fourth pin connected to the 28th pin of the main control chip U3, and its 13th pin connected to the 27th pin of the main control chip U3, for receiving the control signal.

[0011] As an optional implementation, pins 9 and 10 of the radio frequency chip U4 are connected to antenna ANT1 to wirelessly transmit the control signal to the controlled device.

[0012] As an optional implementation, the control signal is in digital format; The sensing signal is in analog format.

[0013] Compared with the prior art, this embodiment has the following beneficial effects: In this embodiment, multiple excitation terminals and sampling terminals in the sensing module constitute a mutual-capacitance touch detection system, which realizes range touch detection, effectively eliminates touch blind spots, and can be used to accurately locate touch coordinates. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in this embodiment, the accompanying drawings used in the embodiment will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the circuit principle of the sensing module in a multi-touch circuit based on capacitive sensing disclosed in this embodiment; Figure 2 This is a schematic diagram of the main control module in a multi-touch circuit based on capacitive sensing disclosed in this embodiment; Figure 3 This is a schematic diagram of the communication module in a multi-touch circuit based on capacitive sensing disclosed in this embodiment. Detailed Implementation

[0016] The technical solutions in this embodiment will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0017] Please see Figures 1-3 This embodiment discloses a multi-touch circuit based on capacitive sensing, comprising: Sensing module, main control module, and communication module; The sensing module includes an excitation unit and a sampling unit, and generates a sensing signal based on the capacitance change between the excitation unit and the sampling unit; The excitation unit includes at least 7 excitation terminals, and the sampling unit includes at least 7 sampling terminals; The main control module generates control signals based on the inductive signals; The communication module transmits control signals to the controlled equipment.

[0018] In this embodiment, a mutual-capacitance touch detection system is formed by setting up multiple excitation terminals and sampling terminals to achieve range touch detection, effectively eliminate touch blind spots, and can be used for accurate positioning of touch coordinates.

[0019] As an optional implementation, the excitation unit includes inductor L1, inductor LF1 and voltage regulator U1; The sampling unit includes an inductor 2L-CMC, a transient suppression diode D1, and a serial communication chip U5; The sampling unit samples the capacitance value between itself and the excitation unit to generate an induced signal.

[0020] Here, the human body is equivalent to a capacitor. When it touches the area between the sampling unit and the excitation unit, the capacitance value between the two changes, and an induction signal is generated when the change occurs.

[0021] As an optional implementation, one end of inductor L1 is energized, and the other end is connected to pins 1 and 3 of inductor LF1; Pin 2 of inductor LF1 is grounded, and pin 4 is connected to pin 1 of voltage regulator U1.

[0022] As an optional implementation, pin 2 of inductor 2L-CMC is connected to pin 1 of transient suppression diode D1, and pin 4 of inductor 2L-CMC is connected to pin 2 of transient suppression diode D1; Pin 1 of transient suppression diode D1 is connected to pin 7 of serial communication chip U5, and pin 3 of transient suppression diode D1 is connected to pin 6 of serial communication chip U5, in order to output the generated induction signal to the main control module.

[0023] As an optional implementation, the main control module uses a main control chip U3, with its 25th pin connected to the 1st pin of the serial communication chip U5, its 23rd pin connected to the 3rd pin of the serial communication chip U5, and its 26th pin connected to the 4th pin of the serial communication chip U5, in order to receive sensing signals.

[0024] As an optional implementation, pins 14, 15, and 16 of the main control chip U3 are used to connect to the LED beads and perform lighting control on the LED beads.

[0025] Here, the main control chip U3 can be directly connected to the LED beads to achieve wired control.

[0026] As an optional implementation, pin 3 of the main control chip U3 is used for drive control, and pin 8 is used for triggering a restart.

[0027] As an optional implementation, the communication module uses an RF chip U4, with its first pin connected to the 32nd pin of the main control chip U3, its second pin connected to the 31st pin of the main control chip U3, its fourth pin connected to the 28th pin of the main control chip U3, and its 13th pin connected to the 27th pin of the main control chip U3, for receiving control signals.

[0028] As an optional implementation, pins 9 and 10 of the RF chip U4 are connected to the antenna ANT1 to wirelessly transmit control signals to the controlled device.

[0029] Here, remote touch control is achieved based on the radio frequency chip U4.

[0030] As an optional implementation, the control signal is in digital format; The induced signal is in analog format.

[0031] Here, the main control chip U4 also converts the acquired analog-format sensing signals into digital-format control signals to ensure that external controlled devices can accurately identify the control logic.

[0032] Compared with the prior art, this embodiment has the following beneficial effects: In this embodiment, multiple excitation terminals and sampling terminals in the sensing module constitute a mutual-capacitance touch detection system, which realizes range touch detection, effectively eliminates touch blind spots, and can be used to accurately locate touch coordinates.

Claims

1. A multi-touch circuit based on capacitive sensing, characterized in that, include: Sensing module, main control module, and communication module; The sensing module includes an excitation unit and a sampling unit, and generates a sensing signal based on the capacitance change between the excitation unit and the sampling unit; The excitation unit includes at least 7 excitation terminals, and the sampling unit includes at least 7 sampling terminals; The main control module generates control signals based on the sensing signals; The communication module transmits the control signals to the controlled device.

2. The multi-touch circuit based on capacitive sensing according to claim 1, characterized in that, include: The excitation unit includes inductor L1, inductor LF1 and voltage regulator U1; The sampling unit includes an inductor 2L-CMC, a transient suppression diode D1, and a serial communication chip U5; The sampling unit samples the capacitance value between itself and the excitation unit to generate the inductive signal.

3. A multi-touch circuit based on capacitive sensing according to claim 2, characterized in that, include: One end of the inductor L1 is connected to power, and the other end is connected to the first and third pins of the inductor LF1; The second pin of the inductor LF1 is grounded, and the fourth pin is connected to the first pin of the voltage regulator U1.

4. A multi-touch circuit based on capacitive sensing according to claim 2, characterized in that, include: The second pin of the inductor 2L-CMC is connected to the first pin of the transient suppression diode D1, and the fourth pin of the inductor 2L-CMC is connected to the second pin of the transient suppression diode D1. The first pin of the transient suppression diode D1 is connected to the seventh pin of the serial communication chip U5, and the third pin of the transient suppression diode D1 is connected to the sixth pin of the serial communication chip U5, so as to output the generated sensing signal to the main control module.

5. A multi-touch circuit based on capacitive sensing according to claim 4, characterized in that, include: The main control module uses a main control chip U3, whose pin 25 is connected to pin 1 of the serial communication chip U5, whose pin 23 is connected to pin 3 of the serial communication chip U5, and whose pin 26 is connected to pin 4 of the serial communication chip U5, in order to receive the sensing signal.

6. A multi-touch circuit based on capacitive sensing according to claim 5, characterized in that, include: Pins 14, 15, and 16 of the main control chip U3 are used to connect to the LED beads and perform lighting control on the LED beads.

7. A multi-touch circuit based on capacitive sensing according to claim 5, characterized in that, include: The third pin of the main control chip U3 is used for drive control, and the eighth pin is used for triggering a restart.

8. A multi-touch circuit based on capacitive sensing according to claim 5, characterized in that, include: The communication module uses an RF chip U4, whose first pin is connected to the 32nd pin of the main control chip U3, its second pin is connected to the 31st pin of the main control chip U3, its fourth pin is connected to the 28th pin of the main control chip U3, and its 13th pin is connected to the 27th pin of the main control chip U3, in order to receive the control signal.

9. A multi-touch circuit based on capacitive sensing according to claim 8, characterized in that, include: Pins 9 and 10 of the radio frequency chip U4 are connected to antenna ANT1 to wirelessly transmit the control signal to the controlled device.

10. A multi-touch circuit based on capacitive sensing according to claim 9, characterized in that, include: The control signal is in digital format; The sensing signal is in analog format.

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