A capacitive induction detection and identification circuit

Abstract

The present invention relates to a capacitive induction detection and identification circuit, comprising a display or execution module, a processing unit, a capacitive induction detection processing conversion unit and an induction detection unit, wherein the display or execution module, the processing unit, the capacitive induction detection processing conversion unit and the induction detection unit are electrically connected in sequence. The beneficial effects of the present invention are as follows: the change in circuit charge caused by approaching an object is converted into a change in detection end capacitance and is detected, thereby realizing the detection of the approach or distance of the detected object, and the circuit can realize non-contact object detection, has a long service life, and is sensitive to detection.

Description

Technical Field

[0001] The invention relates to the field of dental medical instruments, and in particular to a capacitive induction detection and identification circuit. Background Art

[0002] In the field of dental medical devices, it is often necessary to detect and identify necessary matching components such as handles, water bottles, sandblasting bottles, and touch control panels. Traditional contact buttons are more commonly used devices, but traditional contact buttons have the problem of touch deformation fatigue, easy failure, and relatively short lifespan. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a capacitive sensing detection and identification circuit to overcome the deficiencies in the above-mentioned prior art.

[0004] The technical solution of the present invention to solve the above technical problems is as follows: a capacitive sensing detection and identification circuit includes a display or execution module, a processing unit, a capacitive sensing detection processing conversion unit and an inductive detection unit, and the display or execution module, the processing unit, the capacitive sensing detection processing conversion unit and the inductive detection unit are electrically connected in sequence.

[0005] The beneficial effects of the present invention are as follows: the change in circuit charge caused by approaching an object is converted into a change in the capacitance of the detection end and detected, thereby realizing the detection of the approach or distance of the detected object. The circuit can realize non-contact object detection, has a long service life and sensitive detection.

[0006] Based on the above technical solution, the present invention can also be improved as follows.

[0007] Furthermore, the inductive detection unit is an inductive receiving electrode.

[0008] Furthermore, the capacitive sensing detection processing conversion unit includes a resonant circuit and a capacitance level change sensing processing conversion chip, and the sensing receiving electrode, the resonant circuit and the capacitance level change sensing processing conversion chip are electrically connected in sequence.

[0009] The further beneficial effects of adopting the above are: an induction receiving electrode for receiving the charge caused by approaching or moving away from an object; a resonant circuit for matching and collecting signals within the sensing range; a capacitance level change sensing processing conversion chip for converting the changing analog capacitance signal into a corresponding digital signal, and transmitting the digital signal to the processing unit, which finally controls the display or execution module for display or execution; and sensitive detection.

[0010] Furthermore, the number of resonant circuits is at least one, and the multiple resonant circuits are electrically connected to the capacitance level change sensing processing conversion chip respectively; the number of inductive receiving electrodes is at least one, and the multiple inductive receiving electrodes are electrically connected to the multiple resonant circuits one by one respectively.

[0011] A further beneficial effect of the above is that multi-path detection can be achieved.

[0012] Furthermore, the capacitive induction detection processing conversion unit also includes a bidirectional limiter, and the bidirectional limiter is electrically connected between each induction receiving electrode and the resonant circuit.

[0013] The above method has the further beneficial effect of filtering electrostatic shock or certain pulse interference signals to prevent false triggering.

[0014] Furthermore, the capacitive induction detection processing conversion unit also includes an external crystal oscillator module, and the external crystal oscillator module is electrically connected to the capacitance level change induction processing conversion chip.

[0015] Furthermore, the capacitive induction detection processing conversion unit also includes a power supply filter, which is electrically connected to the capacitance level change induction processing conversion chip.

[0016] Further, two ports of the capacitance level change sensing processing conversion chip are connected to pull-up resistors. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system diagram of the capacitive sensing detection and identification circuit of the present invention;

[0018] Figure 2 This is a partial electrical schematic diagram of the capacitive induction detection and identification circuit of the present invention.

[0019] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0020] 1. Display or execution module, 2. Processing unit, 3. Capacitive sensing detection processing conversion unit, 310. Bidirectional limiter, 320. Resonant circuit, 330. Capacitive level change sensing processing conversion chip, 340. External crystal oscillator module, 350. Power supply filter, 4. Induction detection unit. DETAILED DESCRIPTION

[0021] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0022] Example 1

[0023] like Figure 1 As shown, a capacitive sensing detection and identification circuit includes a display or execution module 1, a processing unit 2, a capacitive sensing detection processing conversion unit 3 and an inductive detection unit 4, and the display or execution module 1, the processing unit 2, the capacitive sensing detection processing conversion unit 3 and the inductive detection unit 4 are electrically connected in sequence.

[0024] Example 2

[0025] like Figure 1 As shown, this embodiment is a further improvement on the basis of embodiment 1, and the details are as follows:

[0026] The induction detection unit 4 is an induction receiving electrode, which is used to receive the charge that changes when approaching or moving away from an object.

[0027] Example 3

[0028] like Figure 1 As shown, this embodiment is a further improvement on the basis of embodiment 2, and the details are as follows:

[0029] The capacitive sensing detection processing conversion unit 3 includes a resonant circuit 320 and a capacitance level change sensing processing conversion chip 330, and the sensing receiving electrode, the resonant circuit 320 and the capacitance level change sensing processing conversion chip 330 are electrically connected in sequence;

[0030] The resonant circuit 320 is used to match and collect signals within the sensing range;

[0031] Capacitance level change sensing processing conversion chip 330, used to convert the changed analog capacitance signal into a corresponding digital signal (high and low levels);

[0032] The capacitance level change sensing processing conversion chip 330 is connected to the processing unit 2. Usually, the processing unit 2 is a MCU microprocessor.

[0033] Example 4

[0034] like Figure 1 As shown, this embodiment is a further improvement on the basis of embodiment 3, and the details are as follows:

[0035] There is at least one resonant circuit 320, and the multiple resonant circuits 320 are electrically connected to the capacitance level change sensing processing conversion chip 330 respectively; there is at least one inductive receiving electrode plates, and the multiple inductive receiving electrode plates are electrically connected to the multiple resonant circuits 320 one by one respectively. The so-called at least one can refer to one, two, three, four or other numbers.

[0036] Example 5

[0037] like Figure 1 As shown, this embodiment is a further improvement on the basis of Embodiment 3 or 4, and the details are as follows:

[0038] The capacitive sensing detection processing conversion unit 3 further includes a bidirectional limiter 310, and the bidirectional limiter 310 is electrically connected between each sensing receiving electrode and the resonant circuit 320;

[0039] The bidirectional limiter 310 is used to filter electrostatic shock or certain pulse interference signals to prevent false triggering.

[0040] Example 6

[0041] like Figure 1 As shown, this embodiment is a further improvement on the basis of Embodiment 3, 4 or 5, and the details are as follows:

[0042] The capacitive sensing detection processing conversion unit 3 further includes an external crystal oscillator module 340 , which is electrically connected to the capacitance level change sensing processing conversion chip 330 .

[0043] Example 6

[0044] like Figure 1 As shown, this embodiment is a further improvement on the basis of Embodiment 3, 4, 5 or 6, and the details are as follows:

[0045] The capacitive sensing detection processing conversion unit 3 further includes a power filter 350 , which is electrically connected to the capacitance level change sensing processing conversion chip 330 .

[0046] Example 7

[0047] like Figure 1 As shown, this embodiment is a further improvement on the basis of Embodiment 3, 4, 5, 6 or 7, and the details are as follows:

[0048] Two ports of the capacitance level change sensing processing conversion chip 330 are connected to pull-up resistors.

[0049] like Figure 2 As one of the implementations:

[0050] The capacitive induction detection and identification circuit has two resonant circuits 320 with the same functions, two induction detection units 4, and two bidirectional limiters 310;

[0051] The two sensing detection units 4 are respectively denoted as J20 and J21;

[0052] First route:

[0053] The resonant circuit 320 is composed of an inductor L22, a capacitor C115, a capacitor C118, a resistor R157, a resistor R158, a capacitor C114, and a capacitor C117;

[0054] The bidirectional limiter 310 is composed of a transient suppression diode D44 and a transient suppression diode D45;

[0055] Second route:

[0056] The resonant circuit 320 is composed of an inductor L23, a capacitor C120, a capacitor C123, a resistor R159, a resistor R162, a capacitor C119, and a capacitor C122;

[0057] The bidirectional limiter 310 is composed of a transient suppression diode D46 and a transient suppression diode D47;

[0058] And: the external crystal oscillator module 340 is composed of chip Y1, capacitor C127, resistor R156, and resistor R163;

[0059] The power filter 350 is composed of an inductor L26, a capacitor C124, a capacitor C125, and a capacitor C126;

[0060] The capacitance level change sensing processing conversion chip 330 is denoted as U16, and FDC_SCL, FDC_SDA, and FDC_INT are data transmission connection ports of U16;

[0061] The pull-up resistors are denoted as R160 and R161, and R160 and R161 are connected to the FDC_SDA port and the FDC_SCL port respectively;

[0062] The FDC_INT port is connected to the MCU microprocessor.

[0063] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A capacitive sensing detection and identification circuit, characterized in that: The device comprises a display or execution module (1), a processing unit (2), a capacitive sensing detection processing conversion unit (3) and an inductive detection unit (4), wherein the display or execution module (1), the processing unit (2), the capacitive sensing detection processing conversion unit (3) and the inductive detection unit (4) are electrically connected in sequence, and the inductive detection unit (4) is an inductive receiving electrode; The capacitive sensing detection processing conversion unit (3) comprises: a bidirectional limiter, a resonant circuit, and a capacitance level change sensing processing conversion chip U16; The bidirectional limiter includes: a transient suppression diode D44 and a transient suppression diode D45, and the resonant circuit includes: an inductor L22, a capacitor C114, a capacitor C115, a capacitor C116, a capacitor C117, a capacitor C118, a resistor R157 and a resistor R158; The cathode and anode of the transient suppression diode D45 are connected to the second pin and the first pin of the sensing detection unit J20 respectively, the transient suppression diode D44 is connected in parallel with the transient suppression diode D45, the cathode and anode of the transient suppression diode D44 are connected to the anode and cathode of the transient suppression diode D45 respectively, and the anodes of the transient suppression diode D44 and the transient suppression diode D45 are grounded respectively; Capacitor C116 is connected in parallel with transient suppression diode D44, and inductor L22 is connected in parallel with capacitor C116; The capacitor C115 and the capacitor C118 are connected in series, the series circuit is connected in parallel with the inductor L22, and the capacitor C115 and the capacitor C118 are grounded; Capacitor C114 is connected in series with capacitor C117, and the series circuit is connected in parallel with the series circuit formed by capacitor C115 and capacitor C118, and capacitor C114 and capacitor C117 are grounded; resistor R157 is connected between capacitor C114 and capacitor C115, and resistor R158 is connected between capacitor C117 and capacitor C118; two pins of the capacitance level change sensing processing conversion chip U16 are respectively connected to the series circuit formed by capacitor C114 and capacitor C117; The FDC INT pin of the capacitance level change sensing processing conversion chip U16 is connected to the processing unit (2).

2. A capacitive induction detection and identification circuit according to claim 1, characterized in that: The number of the resonant circuit (320) is at least one, and the resonant circuit (320) is electrically connected to the capacitance level change sensing processing conversion chip (330) respectively; the number of the induction receiving electrode pieces is at least one, and the induction receiving electrode pieces are electrically connected to the resonant circuit (320) one by one respectively.

3. A capacitive induction detection and identification circuit according to claim 1 or 2, characterized in that: The capacitive sensing detection processing conversion unit (3) further comprises an external crystal oscillator module (340), and the external crystal oscillator module (340) is electrically connected to the capacitance level change sensing processing conversion chip (330).

4. A capacitive induction detection and identification circuit according to claim 1 or 2, characterized in that: The capacitive sensing detection processing conversion unit (3) further comprises a power supply filter (350), wherein the power supply filter (350) is electrically connected to the capacitance level change sensing processing conversion chip (330).

5. A capacitive induction detection and identification circuit according to claim 1 or 2, characterized in that: Two ports of the capacitance level change sensing processing conversion chip (330) are connected to pull-up resistors.

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