CN102130675B - Touch sensing circuit and method - Google Patents

Abstract

A touch sensing circuit and method. The signal generators output a pulse signal according to the control signal. The touch detection circuits are configured in an array mode, induction signals are generated according to touch events and pulse signals, and the touch detection circuits in the same row are coupled to the same signal generator. The plurality of sensing circuits are respectively coupled to the touch detection circuits in the same row and generate output signals according to the sensing signals. The controller receives the output signal and outputs a control signal to control one of the signal generators to output a pulse signal, and detects a touch detection circuit corresponding to a touch event according to the output control signal and the output signal.

Description

Touch sensing circuit and method

technical field

The invention relates to a touch sensing circuit, in particular to a touch sensing circuit applied to household electrical appliances.

Background technique

In electrical products, users usually control the operation of the electrical products through the man-machine interface. Generally speaking, this human-machine interface includes two parts: input (Input) and output (Output). The input part refers to the operation of the operation mode by humans. The operation method can be mechanical or electronic to achieve the switch. Purpose, among them, it is a more stable way to achieve switch control by identifying whether there is human body touch, which can avoid problems such as mechanical switches being accidentally touched due to aging or avoiding light-shielding electronic switches due to unexpected unknown objects Interference, so that electrical products into the non-user expected mode of operation.

The traditional touch sensing circuit uses a touch detection circuit to detect the touch event of the human body, and detects the influence of the touch event on the electrical performance of the circuit through a sensing circuit, and finally uses a controller to judge the position where the touch event occurs to Execute the corresponding action.

However, the traditional touch sensing circuit has the problem that the circuit is too complex, and the number of touch detection circuits used is limited by the number of input pins of the controller itself.

Therefore, when the functions of products using man-machine interfaces are increasing, in order to control the cost of products, a touch sensing circuit with simplified circuit design and capable of increasing the number of touch detection circuits is required.

Contents of the invention

In view of this, the present invention provides a touch sensing circuit. Multiple signal generators output a pulse signal according to a control signal. A plurality of touch detection circuits are arranged in an array to generate a sensing signal according to a touch event and the pulse signal, wherein the touch detection circuits in the same row are coupled to the same signal generator. A plurality of sensing circuits are respectively coupled to the touch detection circuits located in the same row, and generate an output signal according to the sensing signals. A controller receives the output signal, outputs the control signal to control one of the signal generators to output the pulse signal, and detects a touch detection corresponding to the touch event according to the output control signal and the output signal circuit.

In addition, the invention provides a touch sensing circuit. Multiple signal generators output a pulse signal according to a control signal. Multiple sensing circuits generate an output signal according to a sensing signal. A plurality of first data lines are arranged along a first direction and are respectively coupled to the corresponding signal generators. A plurality of second data lines are arranged along a second direction perpendicular to the first direction, and are respectively coupled to the corresponding sensing circuits. A plurality of touch detection circuits are respectively arranged at intersections of the first data line and the second data line, and one signal generator of the touch detection circuit receives the pulse signal and generates a sensing signal according to a touch event. A controller receives the output signal, outputs the control signal to control one of the signal generators to output the pulse signal, and detects a touch detection corresponding to the touch event according to the output control signal and the output signal circuit.

In addition, the invention provides a touch sensing circuit. A signal generator outputs a pulse signal according to a control signal. A touch detection circuit generates a sensing signal according to a touch event and the above-mentioned pulse signal, including a first capacitor coupled to the above-mentioned signal generator; a second capacitor coupled to the above-mentioned first capacitor; a first two-pole a tube, having a first positive end coupled to the second capacitor, and a first negative end outputting the sensing signal; a second diode, having a second positive end coupled to a reference power supply, and a second negative terminal coupled to the connection point between the first diode and the second capacitor; a first resistor coupled to the connection point between the first capacitor and the second capacitor and the reference power supply and a touch sensing device coupled to the connection point of the first capacitor and the second capacitor to provide a load effect according to the touch event. A sensing circuit is coupled to the touch detection circuit, and generates an output signal according to the sensing signal. A controller receives the output signal, outputs the control signal, and detects the touch event according to the output signal.

In addition, the present invention provides a touch sensing method, which is applicable to multiple signal generators, including outputting a control signal to control the above-mentioned signal generators to output a pulse signal at different times according to a predetermined sequence; configuring multiple touch signals in an array The detection circuit, the touch detection circuit generates a sensing signal according to a touch event and the pulse signal, wherein the touch detection circuits in the same column are coupled to the same signal generator; the touch detection circuits in the same row are detected An output signal is generated from the sense signal output; and a touch detection circuit corresponding to the touch event is detected according to the control signal output and the output signal.

Description of drawings

FIG. 1 shows a touch sensing circuit according to an embodiment of the invention.

FIG. 2 is a circuit diagram showing a touch sensing circuit according to an embodiment of the invention.

FIG. 3 is a side structural view showing the touch sensing device SW according to an embodiment of the invention.

FIG. 4 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention.

FIG. 5 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention.

FIG. 6 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention.

FIG. 7 is a flowchart showing the operation of the touch sensing method according to an embodiment of the invention.

[Description of main component symbols]

10～Touch sensing circuit;

12, 12A, 51, 51-1～51-N～signal generator;

121 ~ pulse width modulator;

123～switching circuit;

14. 14-11～14-NK～touch detection circuit;

16. 16-1～16-K～ induction circuit;

161～sensing unit;

18 ~ controller;

181～analog-digital converter;

183～sequence controller;

21 ~ circuit board;

23～conductor part;

25 ~ non-conductor part;

C1, C2, C3, C4 ~ capacitance;

D1, D2, D3, D4 ~ diodes;

CTRL ~ control signal;

E-1～E-N, F-1～F-K～data line;

OUTPUT, OUTPUT-1～OUTPUT-K～ output signal;

P, P-1～P-N～pulse signal;

Q ~ transistor;

R1, R2, R3, R4, R5, R6, R7 ~ resistance;

S, S-1 ~ S-K ~ induction signal;

T～sensing area;

SW～touch sensing device;

PWM～pulse width modulation signal;

V ~ DC power supply.

Detailed ways

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, a preferred embodiment will be described in detail below together with the accompanying drawings. Those skilled in the art can use the details described in these embodiments or other embodiments and other applicable structural, logical and electrical changes to implement the invention without departing from the spirit and scope of the invention.

Example:

FIG. 1 shows a touch sensing circuit according to an embodiment of the invention. The touch sensing circuit 10 includes a signal generator 12 , a touch detection circuit 14 , a sensing circuit 16 and a controller 18 . The signal generator 12 outputs the pulse signal P according to the control signal CTRL. According to an embodiment of the present invention, the pulse signal P may be a pulse width modulation (PWM) signal, and the control signal CTRL is provided by the controller 18 to control the operation of the signal generator 12 . The touch detection circuit 14 generates a sensing signal S according to a touch event and the pulse signal P. As shown in FIG. The sensing circuit 16 generates an output signal OUTPUT according to the sensing signal S. The controller 18 detects the above-mentioned touch event according to the output signal OUTPUT, and outputs a control signal CTRL to control the operation of the signal generator 12 .

FIG. 2 is a circuit diagram showing a touch sensing circuit according to an embodiment of the invention. In this embodiment, the signal generator 12 may include a pulse width modulator 121 for enabling according to the control of the control signal CTRL and outputting the pulse signal P. According to an embodiment of the present invention, the pulse signal P may be high Frequency continuous square wave, its frequency can be 400KHz ~ 1MHz.

The touch detection circuit 14 includes capacitors C1, C2, diodes D1, D2, a resistor R1, and a touch sensing device SW. The capacitor C1 is coupled to the signal generator 12, the capacitor C2 is coupled to the capacitor C1, and the diode D1 is coupled between the capacitor C2 and the sensing circuit 16, wherein the positive terminal of the diode D1 is coupled to the capacitor C2, and the negative terminal is coupled to the Sensing circuit 16. The diode D2 is coupled between the connection point of the diode D1 and the capacitor C2 and the reference power supply (the ground point is taken as an example below), wherein the positive terminal of the diode D2 is coupled to the ground point, and the negative terminal is coupled to the connection between the diode D1 and the capacitor C2 Junction. The resistor R1 is coupled between the connection point of the capacitor C1 and the capacitor C2 and the reference power (ground point). The touch sensing device SW is coupled to the connection point of the capacitor C1 and the capacitor C2.

FIG. 3 is a side structural view showing the touch sensing device SW according to an embodiment of the invention. The touch sensing device SW includes a conductor portion 23 disposed on the circuit board 21 and a non-conductor portion 25 disposed on the conductor portion 23 . The non-conductor portion 25 has a sensing area T relative to the surface of the conductor portion 23 . In this embodiment, the material of the non-conductor portion 25 can be glass, acrylic or plastic, and the material of the conductor portion 23 can be iron sheet, copper sheet, etc. When a human body (such as a finger, not shown in the figure) with conductive characteristics touches the sensing area T, the human body, the non-conductive part 21 and the conductive part 23 will produce a capacitive effect, which constitutes a capacitive element equivalently and can provide touch The detection circuit 14 is coupled to the sensing capacitance of the ground point by the connection point of the capacitor C1 and the capacitor C2 to provide a capacitive loading effect.

Referring to FIG. 2 , the sensing circuit 16 includes a resistor R2 , a resistor-capacitor circuit composed of a parallel resistor R3 and a capacitor C3 , and a sensing unit 161 . The resistor R2 is coupled to the connection point of the diode D1 and the diode D2 of the touch detection circuit 14 and receives the sensing signal S. The sensing circuit 16 receives the sensing signal S through the resistor R2, and detects the voltage level at the connection point of the resistors R2, R3 and the capacitor C3 by the sensing unit 161 through the function of the resistor-capacitor circuit formed by the parallel resistor R3 and the capacitor C3, And output the corresponding DC output signal OUTPUT. The controller 18 includes an analog-to-digital conversion circuit for converting the DC output signal OUTPUT into digital data, so as to obtain a voltage level corresponding to the output signal OUTPUT.

When the human body has not touched the touch sensing device SW, the pulse signal P with a high-frequency square wave provided by the signal generator 12 will charge and discharge the capacitors C1 and C2 of the touch detection circuit 14, and the diodes D1 and D2 provide stable After being pressed, the sensing signal S is generated and converted by the sensing circuit 16 into an output signal OUTPUT with a DC voltage level. When the human body touches the touch sensing device SW, the generated sensing capacitance will change the total equivalent capacitance of the touch detection circuit 14. Generally, the total equivalent capacitance of the touch detection circuit 14 will be reduced by 5 to 60%, so the rate of charge and discharge becomes faster and the voltage of the induction signal S generated after the diode is regulated becomes smaller, and the voltage of the output signal OUTPUT generated by the induction circuit 16 is also relatively reduced, and the voltage value decreases After the output signal OUTPUT of the controller 18 is judged by the analog-to-digital conversion circuit, it can be determined that the user has touched the sensing area T.

In addition, the maximum detection voltage of the analog-to-digital conversion circuit of the controller 18 is limited by its reference input power supply. Therefore, another embodiment of the present invention adjusts the voltage range of the pulse signal P to adapt to the analog-to-digital conversion circuit of the controller 18. characteristic. FIG. 4 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention. The difference from the embodiment shown in FIG. 2 lies in the voltage range of the pulse signal P output by the circuit control signal generator 12A. As shown in the figure, the signal generator 12A includes a pulse width modulator 121, a switching circuit 123, a DC power supply V, diodes D3, D4, and resistors R4, R5, R6, R7. The pulse width modulator 121 outputs a pulse width modulation signal PWM. The DC power supply V provides a DC voltage. The positive end of the diode D3 is coupled to the touch detection circuit 14 , and the negative end thereof is coupled to the DC power supply V through the resistor R4 . The positive end of the diode D4 is also coupled to the DC power supply V through the resistor R4, and the negative end thereof is coupled to the touch detection circuit 14 through the resistor R5. The switching circuit 123 includes a transistor Q and a resistor-capacitor circuit composed of a resistor R6 and a capacitor C4 connected in parallel. The transistor Q can be a bipolar transistor (bipolar transistor) or a field-effect transistor (field-effect transistor, FET). Taking a bipolar transistor as an example, the base of the transistor Q is coupled to the pulse width modulator 121 through the resistor R7 , its emitter is coupled to the ground, and its collector is coupled to the junction of the diodes D3 and D4 . In addition, a resistor-capacitor circuit formed by the resistor R6 and the capacitor C4 is coupled between the base of the transistor Q and the ground.

According to the circuit structure of the signal generator 12A shown in FIG. 4, the pulse width modulation signal PWM output by the pulse width modulator 121 limits the current through the resistor R7, and uses the capacitor C4 and the resistor R6 to stabilize the voltage of the control electrode of the transistor Q. The pulse width modulation signal PWM provided by the resistor R7 to the transistor Q can switch the conduction state of the transistor Q, that is, a pulse signal P with a high frequency square wave can be generated at the connection point between the positive terminal of the diode D3 and the negative terminal of the diode D4. The DC level of the pulse signal P can be controlled by adjusting the voltage value of the DC power supply V and the voltage drop of the diode, so that the voltage detected by the controller 18 can be maintained within an allowable range.

FIG. 5 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention. It must be noted that the circuit implementation of the signal generator 51 in FIG. 5 can refer to the signal generator 12 in FIG. 2 or the signal generator 12A in FIG. The circuit structures of 1 to 16-K can be the same as the touch detection circuit 14 and the sensing circuit 16 in FIG. 2 , and the related circuit structures and operations are omitted for brevity.

As shown in the figure, the pulse signal P output by the single signal generator 51 can be supplied to a plurality of touch detection circuits 14 - 11 - 14 - 1K at the same time. Each touch detection circuit 14-11~14-1K respectively inputs the sensing signals S-1~S-K to the corresponding sensing circuits 16-1~16-K, and each sensing circuit 16-1~16-K Signals S-1 ~ S-K respectively output corresponding output signals OUTPUT-1 ~ OUTPUT-K, then the controller 18 can judge the touch event occurred in which touch detection according to the received output signals OUTPUT-1 ~ OUTPUT-K The circuit achieves the purpose of multiple detection touch events.

However, since the number of sensing circuits corresponding to the touch detection circuit depends on the number of input terminals inside the controller 18 (or the number of input terminals of the analog-to-digital converter), the number of touch detection circuits is limited.

FIG. 6 is a circuit diagram showing a touch sensing circuit according to another embodiment of the present invention. In this embodiment, an array type touch detection circuit configuration is used. It must be noted that the circuit implementation of the signal generators 51-1 to 51-N in FIG. 6 can refer to the signal generator 12 in FIG. 2 or the signal generator 12A in FIG. -1～P-N, and the circuit structure of the touch detection circuit 14-11～14-NK and the sensing circuit 16-1～16-K can be the same as the touch detection circuit 14 and the sensing circuit 16 of FIG. 2, and the relevant circuit structure and operation They are omitted for brevity. In addition, the data lines E-1˜E-N are arranged along the first direction and are respectively coupled to the corresponding signal generators 51-1˜51-N, and the data lines F-1˜F-K are arranged along the second direction and connected to the data lines E-1～E-N are orthogonal and are respectively coupled to the corresponding sensing circuits 16-1～16-K, and the touch detection circuits 14-11～14-1NK are respectively arranged on the data lines E-1～E-N and the data lines The intersection of F-1～F-K. According to the array configuration shown in the embodiment of FIG. 6 , the touch detection circuits in the same column are coupled to the same signal generator, and the touch detection circuits in the same row are coupled to the same sensing circuit. For example, the touch detection circuits 14-21˜14-2K in the same row are all coupled to the signal generator 51-2, and the touch detection circuits 14-11˜14-N1 in the same row are all coupled to the same sensing circuit. 16-1.

In the touch sensing circuit shown in FIG. 6 , the controller 18 includes an analog-to-digital converter 181 and a timing controller 183 . The analog-to-digital converter 181 converts the output signals OUTPUT- 1 - OUTPUT-K from an analog format to a digital format to obtain voltage levels of the output signals OUTPUT- 1 - OUTPUT-K. The timing controller 183 outputs a control signal CTRL to control the actions of the signal generators 51 - 1 - 51 -N. The timing controller 183 controls the signal generators 51-1~51-N so that one of the signal generators 51-1~51-N outputs a pulse signal, and the signal generators 51-1~51-N output a pulse signal For example, the order of the signals can be output sequentially according to the order of the signal generators 51 - 1 - 51 -N.

According to an embodiment of the present invention, since the signal generators 51-1~51-N are controlled by the controller 18, only one of them will output the pulse signal, and at the same time, the other signal generators will stop outputting the pulse signal. After the voltage is stabilized, the controller 18 judges whether a touch event is detected according to one of the signal generators of the output signals OUTPUT-1 ~ OUTPUT-K received by the sensing circuit, and stops receiving the current signal after a predetermined time. The generator outputs a pulse signal, and another signal generator outputs a pulse signal, and repeats the above voltage detection process until all signal generators have output a pulse signal, and the touch detection circuit corresponding to the touch event can be identified, and According to the test results, other peripheral functions are driven to form a human-machine interface.

According to the embodiment of the present invention, the voltage stabilization time of the induction circuit needs to be at least 10 microseconds, and the controller 18 can perform at least two detections after the voltage of the induction circuit stabilizes and make an average value to read the voltage as an analog-to-digital converter function. The effective value of the value, and use the difference of the effective value to determine whether the sensing area T has been touched by the user. For example, when the controller 18 enables the signal generator 51-2 to output the pulse signal P-2 and detects that the voltage of the output signal OUTPUT-1 output by the sensing circuit 16-1 changes, the touch event can be known. Occurs at the location of the touch detection circuit 14-21.

In addition, in this embodiment, if the controller 18 has K input pins to respectively receive the output signals OUTPUT-1˜OUTPUT-K, and has N output pins to output N control signals CTRL to respectively control signal generation 51-1 to 51-N, the touch sensing circuit can detect touch events of (N*K) touch detection circuits, compared with the controller in the embodiment shown in FIG. 5, which can only detect K touch detection circuits The touch event can have more detection points. In other words, the same number of detection points can be detected by using a controller chip with fewer pins, which greatly reduces the cost of the circuit.

FIG. 7 is a flowchart showing the operation of the touch sensing method according to an embodiment of the present invention, which can be described here with the circuit diagram disclosed in FIG. 6 . First, the controller 18 outputs the control signal CTRL to control the signal generators 51-1 to 51-N to output a pulse signal (S1) at different times according to a predetermined sequence, that is, under the control of the controller 18, the signal generates Only one of the generators 51 - 1 - 51 -N can output a pulse signal, and when this signal generator stops outputting a pulse signal under the control of the controller 18 , the other signal generator starts to output a pulse signal. Next, the touch detection circuits 14-11~14-NK are arranged in an array (as shown in FIG. 6) (S2), and the touch detection circuits 14-11~14-NK generate an induction according to the touch event and the pulse signal P-N respectively. signal (S3). Next, detect the sensing signals output by the touch detection circuits located in the same row to generate output signals ( S4 ). As shown in FIG. 6 , each of the data lines F- 1 ˜ F-K is respectively coupled to the touch detection circuit in the same row, and outputs output signals OUTPUT- 1 ˜ OUTPUT-K. Finally, the controller 18 detects the touch detection circuit where a touch event occurs according to the output control signal CTRL and the levels of the received output signals OUTPUT- 1 -OUTPUT-K ( S5 ).

According to the touch sensing circuit and method disclosed in the above embodiments, the circuit structure of the traditional touch sensing circuit can be simplified, and the number of detection points for detecting touch behavior can be greatly expanded in an array manner. When the touch sensing circuit and method described in the embodiments of the present invention are applied to home appliances, such as microwave ovens, induction cookers, refrigerators, etc., it can better meet the needs of increasing functions of home appliances.

Although the present invention is disclosed above with preferred embodiments, it is not intended to limit the scope of the present invention. Those skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall prevail as defined by the appended claims.

Claims (22)

1. touch induction circuit comprises:

A plurality of signal generators are exported a pulse signal according to a control signal;

A plurality of touch detection circuits with the array way configuration, produce an induced signal according to a touch event and above-mentioned pulse signal, and the above-mentioned touch detection circuit that wherein is positioned at same row is coupled to identical above-mentioned signal generator;

A plurality of sensor circuits are respectively coupled to the above-mentioned touch detection circuit that is positioned at delegation, produce an output signal according to above-mentioned induced signal; And

One controller, receive above-mentioned output signal, export above-mentioned control signal and export above-mentioned pulse signal to control one of them signal generator of above-mentioned signal generator, and detect above-mentioned touch detection circuit corresponding to above-mentioned touch event according to the above-mentioned control signal of exporting and above-mentioned output signal;

Wherein above-mentioned signal generator comprises:

One pulse-width modulator is exported a pulse width modulating signal;

One direct current power supply provides a direct current voltage;

One first diode is coupled between above-mentioned touch detection circuit and the above-mentioned direct supply, has one first positive terminal and one first negative pole end;

One second diode has one second negative pole end that is coupled to above-mentioned the first positive terminal, and one second positive terminal that is coupled to above-mentioned the first negative pole end; And

One switches circuit, is coupled to above-mentioned pulse-width modulator and above-mentioned direct supply, according to above-mentioned pulse width modulating signal and switching over to export above-mentioned pulse signal in the tie point of above-mentioned the first diode and above-mentioned the second diode.

2. touch induction circuit as claimed in claim 1, wherein above-mentioned signal generator is a pulse-width modulator, exports above-mentioned pulse signal.

3. touch induction circuit as claimed in claim 1, wherein above-mentioned commutation circuit comprises:

One transistor has and is coupled to one of the above-mentioned pulse-width modulator control utmost point, is coupled to one first utmost point of above-mentioned direct supply, and one second utmost point that is coupled to a reference power source; And

One first resistance-capacitance circuit comprises being coupled between the above-mentioned control utmost point and the above-mentioned reference power source and one first resistance and one first electric capacity in parallel.

4. touch induction circuit as claimed in claim 1, wherein above-mentioned touch detection circuit comprises:

One second electric capacity is coupled to above-mentioned signal generator;

One the 3rd electric capacity is coupled to above-mentioned the second electric capacity;

One the 3rd diode has one the 3rd positive terminal that is coupled to above-mentioned the 3rd electric capacity, and one the 3rd negative pole end that is coupled to above-mentioned sensor circuit;

One the 4th diode has one the 4th positive terminal that is coupled to a reference power source, and one the 4th negative pole end that is coupled to the tie point of above-mentioned the 3rd diode and above-mentioned the 3rd electric capacity;

One second resistance is coupled between the tie point and above-mentioned reference power source of above-mentioned the second electric capacity and above-mentioned the 3rd electric capacity; And

One touch induction device is coupled to the tie point of above-mentioned the second electric capacity and above-mentioned the 3rd electric capacity, provides a load effect according to above-mentioned touch event.

5. touch induction circuit as claimed in claim 4, wherein above-mentioned load effect is the capacity load effect.

6. touch induction circuit as claimed in claim 1, wherein above-mentioned sensor circuit comprises:

One second resistance-capacitance circuit has and is coupled between above-mentioned touch detection circuit and the reference power source and one the 3rd resistance and one the 4th electric capacity in parallel; And

One sensing unit detects the voltage level of one of above-mentioned the 3rd resistance and above-mentioned the 4th electric capacity tie point, exports above-mentioned output signal.

7. touch induction circuit as claimed in claim 1, wherein above-mentioned controller comprises:

One analogue-to-digital converters are coupled to above-mentioned sensor circuit, and above-mentioned output signal is converted to digital format by analog format; And

Time schedule controller is exported above-mentioned control signal and is exported above-mentioned pulse signal to control one of them signal generator of above-mentioned signal generator.

8. touch induction circuit comprises:

A plurality of signal generators are exported a pulse signal according to a control signal;

A plurality of sensor circuits produce an output signal according to an induced signal;

A plurality of the first data lines along first direction configuration, are respectively coupled to corresponding above-mentioned signal generator;

A plurality of the second data lines, the second direction configuration along being orthogonal to above-mentioned first direction is respectively coupled to corresponding above-mentioned sensor circuit;

A plurality of touch detection circuits are arranged at respectively the infall of above-mentioned the first data line and above-mentioned the second data line, and one of them signal generator of above-mentioned touch detection circuit receives above-mentioned pulse signal, and produces an induced signal according to a touch event; And

One controller, receive above-mentioned output signal, export above-mentioned control signal and export above-mentioned pulse signal to control one of them signal generator of above-mentioned signal generator, and detect above-mentioned touch detection circuit corresponding to above-mentioned touch event according to the above-mentioned control signal of exporting and above-mentioned output signal;

Wherein above-mentioned signal generator comprises:

One pulse-width modulator is exported a pulse width modulating signal;

One direct current power supply provides a direct current voltage;

One first diode is coupled between above-mentioned touch detection circuit and the above-mentioned direct supply, has one first positive terminal and one first negative pole end;

One second diode has one second negative pole end that is coupled to above-mentioned the first positive terminal, and one second positive terminal that is coupled to above-mentioned the first negative pole end; And

One switches circuit, is coupled to above-mentioned pulse-width modulator and above-mentioned direct supply, according to above-mentioned pulse width modulating signal and switching over to export above-mentioned pulse signal in the tie point of above-mentioned the first diode and above-mentioned the second diode.

9. touch induction circuit as claimed in claim 8, wherein above-mentioned touch detection circuit disposes with array way.

10. touch induction circuit as claimed in claim 9, the above-mentioned touch detection circuit that wherein is positioned at same row is coupled to identical above-mentioned signal generator, and the above-mentioned touch detection circuit that is positioned at delegation is coupled to identical above-mentioned sensor circuit.

11. touch induction circuit as claimed in claim 8, wherein above-mentioned signal generator is a pulse-width modulator, exports above-mentioned pulse signal.

12. touch induction circuit as claimed in claim 8, wherein above-mentioned commutation circuit comprises:

One transistor has and is coupled to one of the above-mentioned pulse-width modulator control utmost point, is coupled to one first utmost point of above-mentioned direct supply, and one second utmost point that is coupled to a reference power source; And

One first resistance-capacitance circuit comprises being coupled between the above-mentioned control utmost point and the above-mentioned reference power source and one first resistance and one first electric capacity in parallel.

13. touch induction circuit as claimed in claim 12, wherein above-mentioned touch detection circuit comprises:

One second electric capacity is coupled to above-mentioned signal generator;

One the 3rd electric capacity is coupled to above-mentioned the second electric capacity;

One the 3rd diode has one the 3rd positive terminal that is coupled to above-mentioned the 3rd electric capacity, and one the 3rd negative pole end that is coupled to above-mentioned sensor circuit;

One the 4th diode has one the 4th positive terminal that is coupled to a reference power source, and one the 4th negative pole end that is coupled to the tie point of above-mentioned the 3rd diode and above-mentioned the 3rd electric capacity;

One second resistance is coupled between the tie point and above-mentioned reference power source of above-mentioned the second electric capacity and above-mentioned the 3rd electric capacity; And

One touch induction device is coupled to the tie point of above-mentioned the second electric capacity and above-mentioned the 3rd electric capacity, provides a load effect according to above-mentioned touch event.

14. touch induction circuit as claimed in claim 13, wherein above-mentioned load is the capacity load effect.

15. touch induction circuit as claimed in claim 8, wherein above-mentioned sensor circuit comprises:

One second resistance-capacitance circuit has and is coupled between above-mentioned touch detection circuit and the reference power source and one the 3rd resistance and one the 4th electric capacity in parallel; And

One sensing unit detects the voltage level of one of above-mentioned the second resistance and above-mentioned the 4th electric capacity tie point, and exports above-mentioned output signal.

16. touch induction circuit as claimed in claim 8, wherein above-mentioned controller comprises:

One analogue-to-digital converters are coupled to above-mentioned sensor circuit, and above-mentioned output signal is converted to digital format by analog format; And

Time schedule controller is exported above-mentioned control signal and is exported above-mentioned pulse signal to control one of them signal generator of above-mentioned signal generator.

17. a touch induction circuit comprises:

One signal generator is exported a pulse signal according to a control signal;

One touch detection circuit produces an induced signal according to a touch event and above-mentioned pulse signal, comprising:

One first electric capacity is coupled to above-mentioned signal generator;

One second electric capacity is coupled to above-mentioned the first electric capacity;

One first diode has one first positive terminal that is coupled to above-mentioned the second electric capacity, and one first negative pole end of exporting above-mentioned induced signal;

One second diode has one second positive terminal that is coupled to a reference power source, and one second negative pole end that is coupled to the tie point of above-mentioned the first diode and above-mentioned the second electric capacity;

One first resistance is coupled between the tie point and above-mentioned reference power source of above-mentioned the first electric capacity and above-mentioned the second electric capacity; And

One touch induction device is coupled to the tie point of above-mentioned the first electric capacity and above-mentioned the second electric capacity, provides a load effect according to above-mentioned touch event;

One sensor circuit is coupled to above-mentioned touch detection circuit, produces an output signal according to above-mentioned induced signal; And

One controller is exported above-mentioned control signal, and detects above-mentioned touch event according to above-mentioned output signal;

Wherein above-mentioned signal generator comprises:

One pulse-width modulator is exported a pulse width modulating signal;

One direct current power supply provides a direct current voltage;

One the 3rd diode is coupled between above-mentioned touch detection circuit and the above-mentioned direct supply, has one the 3rd positive terminal and one the 3rd negative pole end;

One the 4th diode has one the 4th negative pole end that is coupled to above-mentioned the 3rd positive terminal, and one the 4th positive terminal that is coupled to above-mentioned the 3rd negative pole end; And

One switches circuit, is coupled to above-mentioned pulse-width modulator and above-mentioned direct supply, according to above-mentioned pulse width modulating signal and switching over to export above-mentioned pulse signal in the tie point of above-mentioned the 3rd diode and above-mentioned the 4th diode.

18. touch induction circuit as claimed in claim 17, wherein above-mentioned signal generator is a pulse-width modulator, exports above-mentioned pulse signal.

19. touch induction circuit as claimed in claim 17, wherein above-mentioned commutation circuit comprises:

One transistor has and is coupled to one of the above-mentioned pulse-width modulator control utmost point, is coupled to one first utmost point of above-mentioned direct supply, and one second utmost point that is coupled to a reference power source; And

One first resistance-capacitance circuit comprises being coupled between the above-mentioned control utmost point and the above-mentioned reference power source and one second resistance and one the 3rd electric capacity in parallel.

20. touch induction circuit as claimed in claim 17, wherein above-mentioned load is the capacity load effect.

21. touch induction circuit as claimed in claim 17, wherein above-mentioned sensor circuit comprises:

One second resistance-capacitance circuit has and is coupled between above-mentioned touch detection circuit and the reference power source and one the 3rd resistance and one the 4th electric capacity in parallel; And

One sensing unit detects the voltage level of one of above-mentioned the second resistance and above-mentioned the 4th electric capacity tie point, and exports above-mentioned output signal.

22. touch induction circuit as claimed in claim 17, wherein above-mentioned controller comprises:

One analogue-to-digital converters are coupled to above-mentioned sensor circuit, and above-mentioned output signal is converted to digital format by analog format; And

Time schedule controller is exported above-mentioned control signal.

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