CN103186298B - Low standby power consumption driving method and device for capacitive multi-touch - Google Patents

Abstract

The invention provides a capacitive multi-touch driving method and device with low standby power consumption. A capacitive touch panel has a plurality of first conductor lines distributed in a first direction and a plurality of second conductor lines distributed in a second direction. A driving device is connected to a first switch device for driving the capacitive touch panel through the first switch device. A sensing device is connected to a second switch device for sensing the signal of the capacitive touch panel through the second switch device. A control device sets the first and second switch devices in a self-induction mode for the driving device and the sensing device to perform self-induction capacitance detection, and sets the first and second switch devices in a mutual-induction mode for the driving device and the sensing device to perform mutual-induction capacitance detection.

Description

Low standby power consumption driving method and device for capacitive multi-touch

technical field

The invention relates to the technical field of touch panels, in particular to a driving method and device for capacitive multi-touch with low standby power consumption.

Background technique

Most modern consumer electronic devices are equipped with touch pads as one of their input devices. In order to meet the needs of lightness, thinness, shortness, and smallness, the touch panel is also integrated with the panel to form a touch panel, which is convenient for users to input. According to different sensing principles, touch panels can be divided into four types: resistive, capacitive, acoustic, and optical.

The technical principle of the touch panel is that when a finger or other medium touches the screen, it detects voltage, current, sound waves or infrared rays according to different sensing methods, and then measures the coordinate position of the touch point. For example, the resistive type uses the potential difference between the upper and lower electrodes to calculate the position of the pressure point to detect the location of the touch point. The capacitive touch panel uses the capacitance change generated by the electrostatic combination between the arranged transparent electrodes and the human body, and detects its coordinates from the generated current or voltage.

Generally, the driving method of capacitive touch panel is to sense the ground capacitance of each conductor line, and judge whether there is an object approaching the capacitive touch panel through the change of ground capacitance value, which is the existing self-inductive capacitance (selfcapacitance) sense. Measurement, wherein, the self-induction capacitance or the ground capacitance is not the physical capacitance, which is the parasitic and stray capacitance of each conductor line. FIG. 1 is a schematic diagram of a conventional self-capacitance (selfcapacitance) sensing. In a first time period, the conductor lines in the first direction are first driven by the driver in the first direction and the sensor 110 is used to control the conductor lines in the first direction. The self-sensing capacitor charges. Then during the second time period, the driving and sensor 110 detects the voltage on the conductor line in the first direction. Also in the third time period, the driving and sensor 120 in the second direction drives the conductor lines in the second direction to charge the self-inductive capacitance of the conductor lines in the second direction. Then in the fourth time period, the driving and sensor 120 detects the voltage on the conductor line in the second direction.

The existing self-capacitance (selfcapacitance) sensing method in FIG. 1 is to connect a driving circuit and a sensing circuit on the same conductor line at the same time, first drive the conductor line, and then sense the change of the signal on the same conductor line The amount to determine the size of the self-inductance capacitance. Its benefits are:

(1) The amount of data is small, and a single frame (frame) of the touch panel only has m+n pieces of data, which saves hardware costs.

(2) A frame row data (framerowdata) is obtained quickly, so the time required for sensing the touch point is relatively small. Because all conductor lines in the first direction can be sensed simultaneously or one by one, and then drive and sense all conductor lines in the second direction at the same time, two sensing operations of conductor lines in different directions can complete a picture frame , so the amount of data is less, and at the same time, the time required for converting the sensing signal from analog signal to digital signal is much less.

(3) Since the amount of data processing is less, it has lower power consumption.

However, the corresponding disadvantages of the self-capacitance sensing method are:

(1) When there is a floating conductor on the touch panel, such as water droplets, oil stains, etc., it is easy to cause misjudgment of the touch point.

(2) When there are multiple touch points on the touch panel at the same time, there will be a ghost point effect, which makes it difficult for the self-capacitance sensing method to support multi-touch applications.

Another method for driving a capacitive touch panel is to sense the change in the size of the mutual capacitance (mutual capacitance) Cm to determine whether an object is close to the touch panel. Similarly, the mutual capacitance Cm is not a physical capacitance, which is the first The mutual induction capacitance Cm between the conductor line in the first direction and the conductor line in the second direction. FIG. 2 is a schematic diagram of the existing mutual induction capacitance Cm sensing. As shown in FIG. 2, the driver 210 is arranged in the first direction (Y), and the sensor 220 is arranged in the second direction (X). In the first time period T1 In the first half cycle, the driver 210 drives the conductor lines 230 in the first direction, and uses the voltage Vy_1 to charge the mutual induction capacitor Cm250. In the second half cycle of the first time period T1, all the sensors 220 sense all the conductors in the second direction. The voltages Vo_1 , Vo_2 , . . . , Vo_n on the lines 240 are used to obtain n data, and after m driving cycles, m×n data can be obtained.

The advantages of the mutual capacitance Cm sensing method are:

(1) The signals of the floating conductor and the grounding conductor have different directions, so it can be easily judged whether it is human body contact.

(2) Due to the real coordinates of each point, when multiple points are touched simultaneously, the real position of each point can be distinguished, and the mutual induction capacitance Cm sensing method can easily support the application of multi-touch.

Its disadvantages are:

(1) The data volume of a single frame row data (framerow data) is n×m, which is much larger than the data volume of the self-capacitance sensing method.

(2) One direction must be selected and scanned one by one. For example, when there are 20 conductor lines in the first direction Y, 20 sensing actions are required to obtain a complete frame row data. At the same time, due to the large amount of data, the time required for converting the sensing signal from analog signal to digital signal is greatly increased.

(3) Since the amount of data is much larger, the power consumption of data processing will also increase accordingly.

Therefore, there is still room for improvement in the existing technology for detecting capacitive touch panels.

Contents of the invention

The purpose of the present invention is mainly to provide a capacitive multi-touch low standby power consumption driving method and device to achieve the purpose of reducing power consumption, so that it can be applied to a handheld device to prolong the use time of the handheld device.

According to a feature of the present invention, the present invention proposes a capacitive multi-touch low standby power drive system, comprising a capacitive touch panel, a first switcher device, a second switcher device, a drive device, a sensing device, and a control device. The capacitive touch panel has a plurality of first conductor lines distributed in a first direction (Y) and a plurality of second conductor lines distributed in a second direction (X). The first switch device is connected to the capacitive touch panel. The second switch device is connected to the capacitive touch panel. The driving device is connected to the first switch device to drive the capacitive touch panel through the first switch device. The sensing device is connected to the second switch device to sense the signal of the capacitive touch panel through the second switch device. The control device is connected to the first switch device, the second switch device, the drive device, and the sensing device, thereby setting the first switch device and the second switch device in a self-sensing mode to enable the driving device and the sensing device to perform self capacitance (selfcapacitance) detection, and to set the first switch device and the second switch device in a mutual induction mode, so that the driving device and the The sensing device performs mutual capacitance detection.

According to another characteristic of the present invention, the present invention proposes a low standby power consumption driving method for capacitive multi-touch, which is used in a capacitive multi-touch system, the system includes a capacitive touch panel, A first switcher device, a second switcher device, a driving device, a sensing device, and a control device, the capacitive touch panel has a sleep mode, a self-induction capacitance mode, and a mutual induction capacitance mode, the method includes: A) when the capacitive touch panel enters the self-sensing capacitance mode from the sleep mode, the control device determines whether the self-sensing capacitance of the capacitive touch panel has changed, and if so, execute step B , if not, return to step A; B) the control device judges whether there are touch points greater than or equal to a second preset number (A1=A2) on the capacitive touch panel, and if so, execute step C; C) the control device sets the first switch device and the second switch device so that the capacitive touch panel enters the mutual induction capacitance mode, and allows the sensing device to perform mutual capacitance (mutual capacitance) detection test, the control device judges whether the mutual induction capacitance of the capacitive touch panel has changed, if so, execute step D, if not, return to step C; D) the control device judges whether there is more than Or equal to a first preset number (B1=B2) of touch points, if there are, go to step C.

Description of drawings

FIG. 1 is a schematic diagram of conventional self-inductive capacitive sensing.

FIG. 2 is a schematic diagram of the existing mutual induction capacitive sensing.

FIG. 3 is a block diagram of a low standby power consumption drive system for capacitive multi-touch according to the present invention.

FIG. 4 is a circuit diagram of an embodiment of a capacitive multi-touch low standby power consumption driving system of the present invention.

FIG. 5 is a schematic diagram of implementing the first-direction self-sensing capacitive detection in the present invention.

FIG. 6 is a schematic diagram of implementing the second-direction self-sensing capacitive detection according to the present invention.

FIG. 7 is a schematic diagram of performing mutual induction capacitance detection in the present invention.

FIG. 8 is a circuit diagram of another embodiment of the capacitive multi-touch low standby power consumption driving system of the present invention.

FIG. 9 is a schematic diagram of implementing the first-direction self-sensing capacitive detection according to the present invention.

FIG. 10 is a schematic diagram of performing mutual induction capacitance detection in the present invention.

FIG. 11 is a circuit diagram of another embodiment of the capacitive multi-touch low standby power consumption driving system of the present invention.

FIG. 12 is a flow chart of the low standby power consumption driving method of capacitive multi-touch according to the present invention.

[Description of main component symbols]

Drive and Sensor 110 Drive and Sensor 120

Driver 210 Sensor 220

Conductor wire 230 in the first direction and conductor wire 240 in the second direction

Capacitive multi-touch low standby power drive system 300

Capacitive touch panel 310 first switch device 320

The second switching device 330 drives the device 340

Sensing device 350 Control device 360

First conductor wire 311 Second conductor wire 312

Switcher 321 Driver 341

Mutual Capacitance Drivers 343 Self Capacitance Drivers and Sensors 345

Switcher 331 Sensor 351

Mutual Capacitance Sensor 353

Step A～Step D

Ends 321a, 321b, 321c, 331a, 331b, 331c

Ends 321A, 321B, 331A, 331B

detailed description

3 is a block diagram of a capacitive multi-touch low standby power consumption drive system 300 of the present invention, the capacitive multi-touch low standby power drive system 300 includes a capacitive touch panel 310, a first The switch device 320 , a second switch device 330 , a drive device 340 , a sensor device 350 , and a control device 360 .

The capacitive touch panel 310 has a plurality of first conductor lines 311 (Y1-Y6) distributed in a first direction (Y) and a plurality of second conductor lines 312 (X1-X6) distributed in a second direction (X). ).

The first switch device 320 is connected to the capacitive touch panel 310 . Further, the first switch device 320 is connected to the plurality of first conductor lines 311 (Y1˜Y6) or the plurality of second conductor lines 312 (X1˜X6).

The second switch device 330 is connected to the capacitive touch panel 310 . Further, the second switch device 330 is connected to the plurality of first conductor lines 311 (Y1˜Y6) or the plurality of second conductor lines 312 (X1˜X6).

The driving device 340 is connected to the first switch device 320 to drive the capacitive touch panel 310 via the first switch device 320 .

The sensing device 350 is connected to the second switch device 330 to sense the signal of the capacitive touch panel 310 through the second switch device 330 .

The control device 360 is connected to the first switch device 320, the second switch device 330, the driving device 340, and the sensing device 350, thereby setting the first switch device 320 and the second switch device The device 330 is in a self-sensing mode for enabling the driving device 340 and the sensing device 350 to perform self-sensing capacitance (selfcapacitance) detection, and to set the first switch device 320 and the second switch device 330 at A mutual induction mode for enabling the driving device 340 and the sensing device 350 to perform mutual capacitance detection.

When the sensing device 350 performs mutual capacitance (mutual capacitance) detection, the control device 360 determines that there are less than a first preset number (B1=B2) of touch points on the capacitive touch panel 310, the The control device 360 sets the first switch device 320 and the second switch device 330 so that the sensing device 350 performs self capacitance detection. Wherein, the first preset number ( B1 ) is preferably 1.

When the sensing device 350 performs mutual capacitance detection and the control device 360 determines that there are touch points greater than or equal to the first preset number (B1=B2) on the capacitive touch panel 310, The control device 360 maintains the settings of the first switch device 320 and the second switch device 330 so that the sensing device 350 performs mutual capacitance detection.

When the sensing device 350 performs self-capacitance detection and the control device 360 determines that there are less than a second preset number (A1=A2) of touch points on the capacitive touch panel 310, the The control device 360 maintains the settings of the first switch device 320 and the second switch device 330, so that the sensing device 350 performs self-capacitance detection, wherein the second preset number (A1 ) is preferably 2.

When the sensing device 350 performs self-capacitance detection, the control device 360 determines that there are touch points greater than or equal to the second preset number (A1=A2) on the capacitive touch panel 310 , the control device 360 sets the first switch device 320 and the second switch device 330 to allow the sensing device 350 to perform mutual capacitance detection.

4 is a circuit diagram of an embodiment of a capacitive multi-touch low standby power consumption drive system of the present invention, wherein the capacitive touch panel 310 has k first conductor lines 311 distributed in the first direction and in the first direction. k second conductor lines 312 distributed in two directions, wherein k is a positive integer greater than 2, the k first conductor lines 311 and the k second conductor lines 312 have parasitic capacitance and stray capacitance respectively, and the k A mutual inductance capacitance Cm is formed at the overlapping positions between the first conductor lines 311 and the k second conductor lines 312 . For convenience of description, k is 6 in this embodiment.

The first switch device 320 has six 1-to-2 switches 321, and the drive device 340 has six drivers 341, wherein the first end 321a of the i-th 1-to-2 switch 321 is connected to the i-th driver, Its second end 321b is connected to the i-th second conductor line 312 (Xi), and its third end 321c is connected to the i-th first conductor line 311 (Yi). Among them, 1≦i≦6, as in the field Those skilled in the art know that the 1-to-2 switch 321 can be controlled such that the first end 321a is connected to the second end 321b, or the first end 321a is connected to the third end 321c.

The second switch device 330 has six 2-to-1 switches 331, and the sensing device 350 has six sensors 351, wherein the first end 331a of the i-th 2-to-1 switch is connected to the i-th sensor, Its second end 331b is connected to the i-th first conductor line (Yi), and its third end 331c is connected to the i-th second conductor line (Xi). As known to those skilled in the art, the 2-to-1 switching The device 331 can be controlled such that the second end 331b is connected to the first end 331a, or the third end 331c is connected to the first end 321a.

The self-capacitance detection can be divided into a first-direction (Y) self-capacitance detection and a second-direction (X) self-capacitance detection.

FIG. 5 is a schematic diagram of the first direction (Y) self capacitance detection performed by the present invention. As shown in FIG. 5, when performing the self-capacitance (selfcapacitance) in the first direction (Y), the control device 360 sets the i-th 1-to-2 switch 321 and the i-th 2-to-1 switch 331 to The i-th driver 341 is connected to the i-th first conductor line 311 (Yi), and the i-th sensor 351 is connected to the i-th first conductor line 311 (Yi). It is connected to its third terminal 321c through the first terminal 321a of the i-th 1-to-2 switch 321, and the first terminal 331a of the i-th 2-to-1 switch 331 is connected to its second terminal 331b.

FIG. 6 is a schematic diagram of the second direction (X) self capacitance detection performed by the present invention. As shown in FIG. 6, when implementing the self-inductive capacitance in the second direction (X), the control device 360 sets the i-th 1-2 switcher 321 and the i-th 2-to-1 switcher 331, so that the i-th The i-th driver 341 is connected to the i-th second conductor line 312(Xi), and the i-th sensor 351 is connected to the i-th second conductor line 312(Xi). It is connected to the second end 321b of the i-th 1-to-2 switch 321 through the first end 321a, and the first end 331a of the i-th 2-to-1 switch 331 is connected to the third end 331c thereof.

FIG. 7 is a schematic diagram of implementing mutual capacitance detection according to the present invention. As shown in FIG. 7 , when performing the mutual induction capacitance detection, the control device 360 sets the i-th 1-to-2 switch 321 and the i-th 2-to-1 switch 331 so that the i-th driver 341 is connected to To the i-th first conductor line 311 (Yi), the i-th sensor 351 is connected to the i-th second conductor line 312 (Xi). It is connected to the third terminal 321c through the first terminal 321a of the i-th 1-to-2 switch 321, and the first terminal 331a of the i-th 2-to-1 switch 331 is connected to the third terminal 331c.

8 is a circuit diagram of another embodiment of the capacitive multi-touch low standby power consumption drive system of the present invention, wherein the capacitive touch panel 310 has m first conductor lines 311 distributed in the first direction and n second conductor lines 312 distributed in the second direction, wherein m and n are positive integers, and m is not equal to n, the m first conductor lines 311 and the n second conductor lines 312 have parasitic capacitance and For stray capacitance, mutual inductance capacitance Cm is formed at overlapping positions between the m first conductor lines 311 and the n second conductor lines 312 . For convenience of description, in this embodiment, m is 6, and n is 4.

The first switch device 320 has m m+n to 1 switchers 321, the driving device 340 has m drivers 341, the sensing device 350 has n sensors 351, and the jth m+n to 1 switcher The first end 321A of 321 is connected to the jth first conductor line 311 (Yj), and its second end to the m+n+1th end 321B are respectively connected to the m drivers 341 and the n sensors 351, wherein, 1≦j≦m, and as known by those skilled in the art, the m+n to 1 switch 321 can be controlled to select one of the second terminals 321B to be connected to the first terminal 321A. The second switch device 330 has n 1 to m+n switches 331, the first end 331A of the g 1 to m+n switch 331 is connected to the g second conductor line 312 (Xg), which The second end to the m+n+1th end 331B are respectively connected to the m drivers 341 and the n sensors 351, 1≦g≦n, and as known to those skilled in the art, the 1 to m+n switch The line 331 can be controlled such that its first end 331A is connected to one of the second ends 331B.

As shown in Figure 8, the driving device 340 has six drivers 341 (D1-D6), the sensing device 350 has four sensors 351 (S1-S4), and the first switching device 320 has six 10 to 1 Switcher 321, the first end 321A of the first 10-to-1 switcher 321 is connected to the first first conductor line 311 (Y1), and its second to eleventh ends 321B are respectively connected to the six drivers 341 And the four sensors 351 . Other 10-to-1 switches 321 can be connected in the same manner. The second switcher device 330 has four 1 to 10 switchers 331, the first end 331A of the first 1 to 10 switcher 331 is connected to the first second conductor line 312X1, and its second end is connected to the eleventh The terminals 331B are respectively connected to the six drivers 341 and the four sensors 351 . The other 1 to 10 switches 331 can be connected in the same way.

The self-sensing capacitance detection can be divided into a first direction (Y) self-sensing capacitance detection and a second direction (X) self-sensing capacitance (selfcapacitance) detection.

FIG. 9 is a schematic diagram of self capacitance (selfcapacitance) detection in the first direction (Y) and the second direction (X) in the present invention. As shown in FIG. 9, when implementing the first direction (Y) self-inductive capacitance, the control device 360 sets the first 10-to-1 switcher 321 so that the first driver 341 (D1) is connected to the first A first conductor line 311 (Y1), the first sensor 351 (S1) is connected to the first first conductor line 311 (Y1), thereby sensing the capacitance on the first first conductor line 311 (Y1); Then the first driver 341 (D1) is connected to the second first conductor line 311 (Y2), and the first sensor 351 (S1) is connected to the second first conductor line 311 (Y2), thereby sensing the first Capacitance on the 2 first conductor lines 311 (Y2); then the first driver 341 (D1) is connected to the third first conductor line 311 (Y3), and the first sensor 351 (S1) is connected to the third first conductor line 311 (Y3), thereby sensing the capacitance on the third first conductor line 311 (Y3); and so on until sensing the capacitance on the sixth first conductor line 311 (Y6). Among them, only the first driver 341 and the first sensor 351 are used.

And when implementing the second direction (X) self-inductive capacitance, the control device 360 sets the first 1 to 10 switcher 331 so that the first driver 341 (D1) is connected to the first second conductor line 312 (X1), the first sensor 351 (S1) is connected to the first second conductor line 312 (X1), thereby sensing the capacitance on the first second conductor line 312 (X1); then the first driver 341(D1) is connected to the 2nd second conductor line 312(X2), and the 1st sensor 351(S1) is connected to the 2nd second conductor line 312(X2), thereby sensing the 2nd second conductor line Capacitance on 312 (X2); make the 1st driver 341 (D1) connect to the 3rd second conductor line 312 (X3), and the 1st sensor 351 (S1) connect to the 3rd second conductor line 312 (X3), thereby sensing the capacitance on the third second conductor line 312 (X3); and so on until sensing the capacitance on the fourth second conductor line 312 (X4), wherein only the first one is used The driver 341 and the first sensor 351.

When performing the self-inductive capacitance detection in the first direction (Y) and the self-inductive capacitance detection in the second direction (X), only the first driver 341 and the first sensor 351 are used, so that the driving capacity of each Same as the sensing capability to avoid errors.

FIG. 10 is a schematic diagram of implementing mutual capacitance detection according to the present invention. As shown in FIG. 10, when performing the mutual induction capacitance detection, the control device 360 sets the jth 10 to 1 switcher 321 and the gth 1 to 10 switcher 331, so that the jth driver 341 ( Dj) is connected to the jth first conductor line 311 (Yj), the gth sensor 351 (Sg) is connected to the gth second conductor line 312 (Xg), among them, 1≦j≦6, 1≦g≦ 4. In detail, the first driver 341 (D1) is connected to the first first conductor line 311 (Y1), the second driver 341 (D2) is connected to the second first conductor line 311 (Y2), The 3rd driver 341 (D3) is connected to the 3rd first conductor line 311 (Y3), the 4th driver 341 (D4) is connected to the 4th first conductor line 311 (Y4), the 5th driver 341 ( D5) is connected to the fifth first conductor line 311 (Y5), the sixth driver 341 (D6) is connected to the sixth first conductor line 311 (Y6), and the first sensor 351 (S1) is connected to the first 1 second conductor line 312 (X1), 2nd sensor 351 (S2) connected to 2nd second conductor line 312 (X2), 3rd sensor 351 (S3) connected to 3rd second conductor line 312 (X3), the 4th sensor 351 (S4) is connected to the 4th second conductor line 312 (X4).

11 is a circuit diagram of another embodiment of the capacitive multi-touch low standby power consumption drive system of the present invention, wherein the capacitive touch panel 310 has m first conductor lines 311 distributed in the first direction and n second conductor lines 312 distributed in the second direction, wherein m and n are positive integers, and m may be equal to or not equal to n, the m first conductor lines 311 and the n second conductor lines 312 have For parasitic capacitance and stray capacitance, mutual inductance capacitance Cm is formed at the overlap between the m first conductor lines 311 and the n second conductor lines 312 . For convenience of description, in this embodiment, m is 6, and n is 4.

The first switch device 320 has m m+n+z to 1 switches 321 , and the drive device 340 has m mutual capacitance drivers 343 and z self capacitance drivers and sensors 345 . The sensor device 350 has n mutual capacitance sensors 353 . Among them, m, n, z are positive integers.

The first end 321A of the jth m+n+z to 1 switch 321 is connected to the jth first conductor line 311 (Yj), and its second end to the m+n+z+1th end 321B are respectively connected to The m mutual capacitance drivers 343, the z self capacitance drivers and sensors 345 and the n mutual capacitance sensors 353, wherein, 1≦j≦m, and as known to those skilled in the art, the m+n+z to The switch 321 can be controlled to select one of the second terminals 321B to be connected to the first terminal 321A.

The second switch device 330 has n 1 to m+n+z switches 331, and the first end 331A of the g 1 to m+n+z switch 331 is connected to the g second conductor line 312 ( Xg), the second terminal to the m+n+z+1th terminal 331B are respectively connected to the mutual capacitance driver 343, z self-capacitance drivers and sensors 345 and the n mutual capacitance sensors 353, 1≦g≦n, Also as known by those skilled in the art, the 1 to m+n+z switch 331 can be controlled such that its first terminal 331A is connected to one of the second terminals 331B.

As shown in Figure 11, the driving device 340 has 6 mutual capacity drivers 343 (D1-D6) and 1 self-capacitance driver and sensor 345, the sensing device 350 has 4 mutual capacity sensors 353, the first switch The device 320 has six 11-to-1 switches 321, the first end 321A of the first 11-to-1 switch 321 is connected to the first first conductor line 311 (Y1), and its second end to the twelfth end 321B They are respectively connected to the 6 drivers 343 , 1 self-capacitance driver and sensor 345 and the 4 sensors 353 . Other 11-to-1 switches 321 can be connected in the same manner.

The second switch device 330 has four 1-11 switchers 331, the first end 331A of the first 1-11 switcher 331 is connected to the first second conductor line 312 (X1), and its second end is connected to The twelfth terminal 331B is respectively connected to the six drivers 343 , one self-capacitance driver 345 and the four sensors 353 . The other 1 to 11 switches 331 can be connected in the same way.

In the circuit of FIG. 11 , when self-capacitance detection is performed, the one self-capacitance driver and the sensor 345 are used to pass through the six 11-to-1 switches 321 and the four 1-to-1 switches 331 respectively. , and sequentially connected to the six first conductor lines 311 distributed in the first direction and the four second conductor lines 312 distributed in the second direction, so as to perform self-inductive capacitance detection.

When performing mutual induction capacitance detection, use the 6 mutual capacitance drivers 343 and 4 mutual capacitance sensors 353 to connect to the The six first conductor lines 311 distributed in the first direction and the four second conductor lines 312 distributed in the second direction are used for mutual capacitance detection.

As for the detailed setting of the switcher, those skilled in the art can easily complete it based on FIG. 8, FIG. 9, FIG.

In the circuit of FIG. 11, since the 6 mutual capacitance drivers 343 and the 4 mutual capacitance sensors 353 only need to implement the circuits of mutual capacitance driving and mutual capacitance sensing respectively, it can be compared with the 6 drivers in FIG. The areas of 341 and four sensors 351 are much reduced.

FIG. 12 is a flow chart of the low standby power consumption driving method of capacitive multi-touch according to the present invention. The method is used in a capacitive multi-touch system 300 as shown in FIG. Control panel 310, a first switcher device 320, a second switcher device 330, a driving device 340, a sensing device 350, and a control device 360, the capacitive touch panel 310 has a sleep mode, a Self-sensing capacitance mode, and a mutual induction capacitance mode.

In step A, when the capacitive touch panel 310 enters the self-sensing capacitance mode from the sleep mode, the control device 360 determines whether the self-sensing capacitance of the capacitive touch panel 310 has changed, and if so, performs step B , if not, return to step A. The control device 360 determines whether the self-sensing capacitance of the capacitive touch panel 310 has changed, and compares a pre-stored self-sensing capacitance data of the capacitive touch panel 310 with the capacitive touch detected by the sensing device 350. The self-sensing capacitance data of the control panel 310.

In step B, the control device 360 determines whether there are touch points greater than or equal to a second preset number (A1=A2) on the capacitive touch panel 310, and if so, step C is executed. Wherein, the second preset number (A1=A2) is preferably 2.

In step C, the control device 360 sets the first switch device 320 and the second switch device 330 so that the capacitive touch panel 310 enters the mutual induction capacitive mode, and the sensing device 350 Execute mutual capacitance (mutual capacitance) detection, the control device 360 judges whether the mutual capacitance of the capacitive touch panel 310 has changed, if yes, execute step D, if not, it means that a misjudgment may be made in step B, so repeat Go back to step A.

In step C, the control device 360 determines whether the mutual induction capacitance of the capacitive touch panel 310 has changed, and compares a pre-stored mutual induction capacitance data of the capacitive touch panel 310 with the data sensed by the sensing device 350. The mutual induction capacitance data of the capacitive touch panel 310 .

In step D, the control device 360 determines whether there are touch points greater than or equal to a first preset number (B1=B2) on the capacitive touch panel 310, and if so, step C is executed. Wherein, the first preset number (B1=B2) is preferably 1.

In step B, the control device 360 determines that there are no touch points greater than or equal to the second preset number (A1=A2) on the capacitive touch panel 310, and executes step A.

In other embodiments, when the control device 360 determines that the number of touch points on the capacitive touch panel 310 that is greater than or equal to the second preset number (A1=A2) exceeds a preset value, it indicates using If the capacitive touch panel 310 is not used, it can enter sleep mode to save power.

In step D, the control device 360 determines that there are no touch points greater than or equal to the first preset number (B1=B2) on the capacitive touch panel 310, and executes step A.

It can be known from the foregoing description that initially, the driving system 300 in the capacitive multi-touch low standby power consumption mode of the present invention is in the self-sensing capacitance mode to detect the self-sensing capacitance. According to the number of detected touch points, if touch If the total number of touch points is less than the second preset number (A1=A2) (for example: ≦1), then continue to maintain in the self-inductive capacitance mode, if the total number of touch points is greater than or equal to the second preset number (A1=A2) (for example: ≧2), enter the mutual induction capacitance mode to improve the detection performance of multi-touch.

After entering the mutual induction capacitance mode, the sensing device 350 will sense the voltage signal corresponding to the mutual induction capacitance. After the control device 360 filters out the noise in the voltage signal, it will judge the actual number of touch points. If the total number of touch points is greater than or equal to the first preset number (B1=B2) (for example: ≧1), it will continue to maintain the mutual induction capacitance mode, if the total number of touch points is less than the first preset number (B1=B2) (for example: ≦ 0), then jump back to use self-sensing capacitor mode, thereby saving power. In this way, the purpose of reducing power consumption can be achieved, so that it can be applied to handheld devices to prolong the use time of the handheld devices.

From the above, it can be known that the present invention has features that are very different from the prior art in terms of purpose, means and efficacy, and has great practical value. However, it should be noted that the above-mentioned embodiments are examples only for convenience of description, and the scope of rights claimed by the present invention should be determined by the claims, rather than limited to the above-mentioned embodiments.

Claims (20)

1. A capacitive multi-touch low standby power drive system, comprising: A capacitive touch panel, having a plurality of first conductor lines distributed in a first direction and a plurality of second conductor lines distributed in a second direction, wherein the first conductor lines and the second conductor lines respectively have parasitic capacitance and stray capacitance, where mutual inductance capacitance is formed at the overlap between the first conductor line and the second conductor line; a first switch device connected to the capacitive touch panel; a second switch device connected to the capacitive touch panel; a driving device, connected to the first switch device, for driving the capacitive touch panel through the first switch device; a sensing device, connected to the second switch device, for sensing the signal of the capacitive touch panel through the second switch device; and a control device, connected to the first switch device, the second switch device, the driving device, and the sensing device, thereby setting the first switch device and the second switch device in a self-sensing mode for enabling the driving device and the sensing device to perform self-sensing capacitance detection, and setting the first switching device and the second switching device in a mutual sensing mode for enabling the driving device and the The sensing device performs mutual capacitance detection; Wherein, when the sensing device executes the self-sensing capacitive detection, when the control device determines that there are less than a second preset number of touch points on the capacitive touch panel, the control device maintains the first switching setting of the switching device and the second switching device so that the sensing device performs the self-inductive capacitance detection; otherwise, the control device sets the first switching device and the second switching device to use enabling the sensing device to perform the mutual capacitance detection; Wherein, the capacitive touch panel has k first conductor lines distributed in the first direction and k second conductor lines distributed in the second direction, and the first switch device has k 1-to-2 switches, the driving device has k drivers, the first end of the i-th 1-to-2 switch is connected to the i-th driver, and the second end is connected to the i-th second conductor line, and Its third end is connected to the i-th first conductor line, where 1≦i≦k. 2. The capacitive multi-touch low standby power drive system according to claim 1, wherein when the sensing device performs the mutual induction capacitance detection, the control device determines that the capacitive touch panel When there are less than a first predetermined number of touch points, the control device sets the first switch device and the second switch device to enable the sensing device to perform the self-sensing capacitance detection. 3. The capacitive multi-touch low standby power drive system according to claim 2, wherein when the sensing device performs the mutual induction capacitance detection, the control device determines that the capacitive touch panel When there are more than or equal to the first preset number of touch points, the control device maintains the settings of the first switch device and the second switch device to enable the sensing device to perform the mutual sensing Capacitive detection. 4. The low standby power consumption driving system of capacitive multi-touch according to claim 1, wherein the second switcher device has k 2-to-1 switchers, the sensing device has k sensors, and the second The first end of the i 2-to-1 switcher is connected to the i-th sensor, the second end is connected to the i-th first conductor line, and the third end is connected to the i-th second conductor line. 5. The capacitive multi-touch low standby power drive system according to claim 4, wherein the self-inductive capacitance detection can be divided into a first direction (Y) self-inductive capacitance detection and a second direction Direction (X) self-sensing capacitance detection. 6. The capacitive multi-touch low standby power driving system according to claim 5, wherein, when performing the first direction self-sensing capacitance, the control device sets the ith 1-2 switch and the i-th 2-to-1 switcher for connecting the i-th driver to the i-th first conductor line, and connecting the i-th sensor to the i-th first conductor line. 7. The capacitive multi-touch low standby power drive system according to claim 6, wherein, when performing the second direction self-sensing capacitance, the control device sets the ith 1-2 switch and the i-th 2-to-1 switcher for connecting the i-th driver to the i-th second conductor line, and connecting the i-th sensor to the i-th second conductor line. 8. The capacitive multi-touch low standby power drive system according to claim 7, wherein, when performing the mutual induction capacitance detection, the control device sets the i-th 1-2 switch and the i-th There are i 2-to-1 switchers, so that the i-th driver is connected to the i-th first conductor line, and the i-th sensor is connected to the i-th second conductor line. 9. The capacitive multi-touch low standby power drive system according to claim 3, wherein the capacitive touch panel has m first conductor lines distributed in the first direction and The number of second conductor lines distributed in the second direction is n, the first switch device has m m+n to 1 switchers, the drive device has m drivers, and the sensing device has n sensors, The first end of the jth m+n to 1 switch is connected to the jth first conductor line, and its second end to the m+n+1 end are respectively connected to the m drivers and the n sensors, m , n is a positive integer, and m is not equal to n, 1≦j≦m. 10. The capacitive multi-touch low standby power drive system according to claim 9, wherein the second switch device has n switches from 1 to m+n, and the g-th switch from 1 to m+n The first end of the switch is connected to the g second conductor line, and the second end to the m+n+1 end are respectively connected to the m drivers and the n sensors, 1≦g≦n. 11. The capacitive multi-touch low standby power drive system according to claim 10, wherein the self-sensing capacitance detection can be divided into a first-direction self-sensing capacitance detection and a second-direction self-sensing Capacitance detection, when performing the first-direction self-sensing capacitance detection, the control device sets the jth m+n to 1 switch so that the first driver is connected to the jth first conductor line, and the first sensor is connected to the jth first conductor line. 12. The capacitive multi-touch low standby power drive system according to claim 11, wherein when performing the second direction self-sensing capacitance, the control device sets the g-th 1 to m+n A switch is used to connect the first driver to the g-th second conductor line, and connect the first sensor to the g-th second conductor line. 13. The capacitive multi-touch low standby power driving system according to claim 12, wherein when performing the mutual induction capacitance detection, the control device sets the jth m+n to 1 switching device and the gth 1 to m+n switcher for connecting the jth driver to the jth first conductor line, and the gth sensor to connect to the gth second conductor line. 14. The capacitive multi-touch low standby power driving system according to claim 3, wherein the capacitive touch panel has m first conductor lines distributed in the first direction and The number of second conductor lines distributed in the second direction is n, the first switch device has m m+n+z to 1 switchers, and the drive device has m mutual-capacitance drivers and z self-capacity drivers and a sensor, the sensing device has n mutual capacitance sensors, the first end of the jth m+n+z to 1 switch is connected to the jth first conductor line, and the second end thereof is connected to the m+n+z The +1 terminal is respectively connected to the m mutual-capacitance drivers, the z self-capacitance drivers and sensors, and the n mutual-capacitance sensors, m and n are positive integers, and m is not equal to n, 1≦j≦m. 15. The capacitive multi-touch low standby power drive system according to claim 14, wherein the second switch device has n 1 to m+n+z switches, and the gth 1 to m The first end of the +n+z switch is connected to the g second conductor line, and the second end to the m+n+z+1 end are respectively connected to the m mutual-capacitance drivers, the z self-capacitance drivers and For the sensor and the n mutual capacitance sensors, 1≦g≦n. 16. A capacitive multi-touch driving method for a capacitive multi-touch system, comprising a capacitive touch panel, a first switch device, a second switch device, a drive device, a sensing device, and a control device, the capacitive touch panel has a plurality of first conductor lines and a plurality of second conductor lines, the capacitive touch panel has a sleep mode, a self-sensing capacitance mode, and a mutual induction capacitance mode, the method comprising: A) When the capacitive touch panel enters the self-sensing capacitance mode from the sleep mode, the control device judges whether the self-sensing capacitance of the capacitive touch panel has changed, if so, perform step B), if not, repeat Go back to step A); B) the control device judges whether there are touch points greater than or equal to a second preset number on the capacitive touch panel, and if so, execute step C); C) The control device sets the first switcher device and the second switcher device, the first switcher device is connected between the driving device and the plurality of first conductor lines, and the second switcher device is connected to Between the plurality of second conductor lines and the sensing device, the capacitive touch panel enters the mutual induction capacitance mode, and the sensing device performs mutual induction capacitance detection, and the control device judges the capacitance Whether the mutual induction capacitance of the type touch panel has changed, if so, perform step D), if not, return to step A); and D) The control device judges whether there are touch points greater than or equal to a first preset number on the capacitive touch panel, and if so, execute step C). 17. The driving method of capacitive multi-touch according to claim 16, wherein, in step B), when the control device determines that there is no more than or equal to the second preset number on the capacitive touch panel If the point is touched, step A) is performed. 18. The driving method of capacitive multi-touch according to claim 17, wherein, in step D), when the control device determines that there is no more than or equal to the first preset number on the capacitive touch panel If the point is touched, step A) is performed. 19. The driving method of capacitive multi-touch according to claim 16, wherein, in step A), the control device judges whether the self-sensing capacitance of the capacitive touch panel changes, and compares the capacitive touch A pre-stored self-sensing capacitance data in the control panel and the self-sensing capacitance data of the capacitive touch panel sensed by the sensing device. 20. The driving method of capacitive multi-touch according to claim 19, wherein, in step C), the control device judges whether the mutual induction capacitance of the capacitive touch panel changes, and compares the capacitive touch A pre-stored mutual induction capacitance data in the control panel and the mutual induction capacitance data of the capacitive touch panel sensed by the sensing device.