TWI457807B - Touch apparatus - Google Patents

Description

Touch device

The present invention relates to a touch device, and more particularly to a touch device capable of reducing noise during signal transmission and having low quiescent current.

With the rapid development of technology, most electronic devices, such as notebook computers, mobile phones, or portable multimedia players, are usually equipped with a touch panel as a new generation input interface. The touch panel can be roughly classified into a resistive type, a capacitive type, an infrared type, and an ultrasonic type. Among them, a resistive touch panel and a capacitive touch panel are the most common products.

The capacitive touch panel changes the voltage on the capacitance of the touch panel by approaching or touching the touch panel via a finger or a conductor material. When the touch panel detects a voltage change on the capacitor, the internal circuit of the touch panel processes the voltage change so that the position of the finger or the conductor material is close or touched, and the touch position is performed. Functional operation.

However, in the process of processing the voltage on the capacitor, the signal is transmitted and processed between the internal circuits of the touch panel. Since the signal retransmission process may carry a lot of noise components, if the touch panel is not effective. Processing the noise entrained by the signal may cause the signal to be distorted due to noise, and the touch panel may malfunction.

The invention provides a touch device, which effectively reduces noise during signal transmission and has low quiescent current.

The invention provides a touch device with a touch capacitor and a touch control unit. The touch control unit includes a signal sample storage unit, a switch unit, and a signal processing unit. The signal sampling and holding unit is coupled to the contact capacitor for sampling and storing the voltage on the touch capacitor during the generation of the sampling signal to generate a touch voltage, and sampling and saving the touch capacitor during the enable of the charge reset signal The voltage is applied to generate a reset voltage, and the signal sampling and holding unit further generates an average voltage of the touch voltage and the reset voltage according to the equalization signal. The switch unit is coupled to the signal sampling and holding unit for receiving and transmitting the touch voltage, the reset voltage and the average voltage according to the first control signal. The signal processing unit is coupled to the switch unit, and receives the touch voltage, the reset voltage, the average voltage, and the common voltage, and couples the touch voltage, the reset voltage, the average voltage, and the common voltage according to the second control signal to generate The first coupling voltage is coupled to the second coupling voltage.

In an embodiment of the invention, the signal sampling and holding unit includes a first switch, a first capacitor, a second switch, a second capacitor, a third switch, a first buffer, and a second buffer. The first end of the first switch receives the touch voltage, and the control end of the first switch is controlled by the sampling signal to determine whether the first switch is turned on or off. The first end of the first capacitor is coupled to the second end of the first switch, the second end of the first capacitor is coupled to the ground, and the first capacitor is used to store the touch voltage. The first end of the second switch receives the reset voltage, and its control terminal is controlled by the charge reset signal to determine whether the second switch is turned on or off. The second end of the second capacitor is coupled to the second end of the second switch, the second end of the second capacitor is coupled to the ground, and the second capacitor is used to store the reset voltage. The first end of the third switch is coupled to the first end of the first capacitor, the second end of the third switch is coupled to the first end of the second capacitor, and the control end of the third switch is controlled by the equalization signal to make the first A first end of the capacitor and a first end of the second capacitor are coupled to each other to generate an average voltage. The first buffer is coupled to the first end of the first capacitor for receiving and outputting the touch voltage and the average voltage. The second buffer is coupled to the first end of the second capacitor for receiving and outputting the reset voltage and the average voltage.

In an embodiment of the invention, the switch unit includes a fourth switch and a fifth switch. The first end of the fourth switch is coupled to the signal sampling and holding unit, the second end of which is coupled to the signal processing unit, and the control end of the fourth switch is controlled by the first control signal, and determines that the fourth switch is turned on and off to transmit Touch voltage and the average voltage. The first end of the fifth switch is coupled to the signal sampling and holding unit, the second end of the fifth switch is coupled to the signal processing unit, and the control end of the fifth switch is controlled by the first control signal, and determines that the fifth switch is turned on or off. To transmit the reset voltage and the average voltage

In an embodiment of the invention, the signal processing unit includes a third capacitor, a fourth capacitor, a sixth switch, a seventh switch, a third buffer, and a fourth buffer. The first end of the third capacitor receives the touch voltage and the average voltage. The first end of the fourth capacitor receives the reset voltage and the average voltage. The first end of the sixth switch is coupled to the second end of the third capacitor, the second end of the sixth switch receives the common voltage, and the control end is controlled by the second control signal to determine whether the sixth switch is turned on or off. The first end of the seventh switch is coupled to the second end of the sixth switch, the second end of the seventh switch is coupled to the second end of the fourth capacitor, and the control end is coupled to the control end of the sixth switch, according to the second The control signal determines whether the seventh switch is turned on or off. The input end of the third buffer is coupled to the second end of the third capacitor, and the output end thereof outputs a first coupling voltage. The input end of the fourth buffer is coupled to the second end of the fourth capacitor, and the output end thereof outputs a second coupling voltage. Wherein, during the enabling period of the second control signal, the sixth switch and the seventh switch are turned on, so that the third capacitor couples the common voltage, the touch voltage and the average voltage to generate the first coupling voltage and make the fourth capacitive coupling share The voltage, the reset voltage, and the average voltage are used to generate a second coupling voltage.

In an embodiment of the invention, the touch device further includes an eighth switch. The first end of the eighth switch is coupled to the contact control capacitor, the second end of the eighth switch is coupled to the ground end, and the control end of the eighth switch is controlled by the reset signal. Wherein, during the enable period of the reset signal, the eighth switch is turned on, so that the voltage on the touch capacitor is discharged through the eighth switch.

In an embodiment of the invention, the eighth switch comprises a transistor. The germanium of the transistor is extremely coupled to the contact capacitor, and the gate of the transistor is coupled to receive a reset signal, and the source terminal of the transistor is coupled to the ground.

In an embodiment of the invention, the touch control unit further includes an analog digital converter. The analog-to-digital converter is coupled to the signal processing unit for receiving the first coupling voltage and the second coupling voltage, and performing analog-digital conversion on the first coupling voltage and the second coupling voltage to output the first digit signal and the second digit signal .

In an embodiment of the invention, the touch control device further has a second touch capacitor, and the touch control unit further includes a second signal sample storage unit and a second switch unit. The second signal sampling and holding unit is coupled to the second touch capacitor for sampling and saving the voltage on the second touch capacitor to generate the second touch voltage during the enabling of the second sampling signal, and is at the second charge Sampling and storing the voltage on the second touch capacitor to generate a second reset voltage, and the second signal sampling and holding unit further generates the second touch voltage and the second reset according to the second equalization signal. The second average voltage of the voltage. The second switching unit is coupled to the second signal sampling and holding unit and the signal processing unit for receiving and transmitting the second touch voltage, the second reset voltage and the second average voltage according to the third control signal. The signal processing unit receives the second touch voltage, the second reset voltage, and the second average voltage, and performs the second touch voltage, the second reset voltage, the second average voltage, and the common voltage according to the second control signal. Coupling to generate a third coupling voltage and a fourth coupling voltage.

The invention samples and saves the voltage on the touch capacitor during the enablement of the sampling signal to generate a touch voltage and samples and saves the voltage on the touch capacitor during the enable of the charge reset signal by the signal sampling and holding unit. A reset voltage is generated, and an average voltage of the touch voltage and the reset voltage is generated according to the equalization signal. Thereafter, the touch voltage, the reset voltage, and the average voltage are respectively transmitted to the signal processing unit through the switch unit. Then, the touch voltage, the reset voltage, the average voltage, and the common voltage are coupled by the signal processing unit to generate the first coupling voltage and the second coupling voltage. In this way, the noise during signal transmission and the low quiescent current of the touch device can be effectively reduced.

The above described features and advantages of the present invention will be more apparent from the following description.

DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the exemplary embodiments embodiments In addition, wherever possible, the same reference numerals in the drawings

FIG. 1 is a schematic diagram of a touch device according to an embodiment of the invention. Referring to FIG. 1 , the touch device 100 has a touch capacitance CT1 and includes a touch control unit 110 . The touch control unit 110 includes a signal sample holding unit 120, a switch unit 130, and a signal processing unit 140. The touch capacitor CT1 is, for example, a touch pad (not shown) of an area of the touch device 100 for receiving the pressing information when the user presses the touch device 100 and storing the corresponding voltage. The touch capacitor CT1 stores different voltage values in response to the user pressing the touch device 100.

The signal sampling and holding unit 120 is coupled to the contact capacitor CT1 for sampling and storing the voltage on the touch capacitor CT1 during the enabling of the sampling signal SS1 to generate the touch voltage VT1, and during the enabling of the charge reset signal SR1. Sample and save the voltage of CT1 on the touch capacitor to generate reset voltage VR1. In addition, the signal sampling and holding unit 120 further generates an average voltage of the touch voltage VT1 and the reset voltage VR1 according to the equalization signal VC1.

For example, when the user presses the touch device 100, the information pressed by the user is converted into a voltage through a voltage conversion unit (not shown), and is saved by the touch capacitor CT1. At this time, the touch device 100 enables the sampling signal SS1, so that the signal sampling and holding unit 120 samples and saves the voltage on the touch capacitor CT1 during the enabling of the sampling signal SS1 to generate the touch voltage VT1. Then, the touch device 100 disables the sampling signal SS1 and discharges the voltage on the touch capacitor CT1, so that the touch capacitor C1 receives the message pressed by the next user. After the voltage on the touch capacitor CT1 is discharged, the touch device 100 generates a charge reset signal SR1, so that the signal sample and hold unit 120 samples and saves the touch capacitor CT1 during the enable of the charge reset signal SR1. Voltage to generate reset signal VR1.

The switch unit 130 is coupled to the signal sampling and holding unit 120 for receiving and transmitting the touch voltage VT1, the reset voltage VR1 and the average voltage according to the first control signal V1. The signal processing unit 140 is coupled to the switch unit 130 for receiving the touch voltage VT1, the reset voltage VR1, the average voltage and the common voltage Vcom, and according to the second control signal V2, the touch voltage VT1, the reset voltage VR1, and the average The voltage is coupled to the common voltage Vcom to generate a first coupling voltage and a second coupling voltage.

In the present embodiment, the signal sample and hold unit 120 includes switches 121, 122, and 123, capacitors C1_1 and C2_1, and buffers 124 and 125. The first end of the switch 121 receives the touch voltage VT1, and the control end of the switch 121 is controlled by the sampling signal SS1 to determine whether the switch 121 is turned on or off. For example, when the sampling signal SS1 is enabled, the switch 121 is turned on to transmit the voltage on the touch capacitor CT1, and when the sampling signal SS1 is disabled, the switch 121 is not turned on. The first end of the capacitor C1_1 is coupled to the second end of the switch 121, and the second end of the capacitor C1_1 is coupled to the ground. Moreover, when the switch 121 is turned on, the capacitor C1_1 samples and stores the voltage on the touch capacitor CT1 to generate the touch voltage VT1.

The first terminal of the switch 122 receives the reset voltage VR1, and the control terminal of the switch 122 is controlled by the charge reset signal SR1 to determine whether the switch 122 is turned on or off. For example, when the charge reset signal SR1 is enabled, the switch 122 is turned on to transfer the voltage on the touch capacitor CT1, and when the charge reset signal SR1 is disabled, the switch 122 is not turned on. The first end of the capacitor C2_1 is coupled to the second end of the switch 122, and the second end of the capacitor C2_1 is coupled to the ground. When the switch 122 is turned on, the capacitor C2_1 samples and saves the voltage on the touch capacitor CT1 to generate a weight. Set voltage VR1.

The first end of the switch 123 is coupled to the first end of the capacitor C1_1, the second end of the switch 123 is coupled to the first end of the capacitor C2_2, and the control end is controlled by the equalization signal VC1, so that the first end of the capacitor C1_1 and the capacitor The first ends of C2_1 are coupled to each other to generate an average voltage. That is, when the switch 123 is turned on, the first end of the capacitor C1_1 is connected to the first end of the capacitor C2_1, so that the touch sharing voltage VT1 and the reset voltage VR1 have a charge sharing effect to generate an average voltage. This average voltage is, for example, (VT+VR)/2.

The buffer 124 is coupled to the first end of the capacitor C1_1 for receiving the touch voltage VT1 and the average voltage, and buffering the touch voltage VT1 and the average voltage for output. The buffer 125 is coupled to the first end of the capacitor C2_1 for receiving the reset voltage VR1 and the average voltage, and buffering the reset voltage VR1 and the average voltage for output.

The switch unit 130 includes switches 131 and 132. The first end of the switch 131 is coupled to the signal sampling and holding unit 120. The second end of the switch 131 is coupled to the signal processing unit 140. The control end of the switch 131 is controlled by the first control signal V1, and the switch 131 is turned on and off. To transmit the touch voltage VT1 and the average voltage. The first end of the switch 132 is coupled to the signal sampling and holding unit 120. The second end of the switch 132 is coupled to the signal processing unit 140. The control end of the switch 132 is controlled by the first control signal V1, and the switch 132 is turned on or off. The reset voltage VR1 and the average voltage are transmitted.

Signal processing unit 140 includes capacitors C3 and C4, switches 141 and 142, and buffers 143 and 144. The first end of the capacitor C3 receives the touch voltage VT1 and the average voltage. The first end of the capacitor C4 receives the reset voltage VR1 and the average voltage. The first end of the switch 141 is coupled to the second end of the capacitor C3, the second end of the switch 141 receives the common voltage Vcom, and the control end of the switch 141 is controlled by the second control signal V2 to determine whether the switch 141 is turned on or off.

The first end of the switch 142 is coupled to the second end of the switch 141, the second end of the switch 142 is coupled to the second end of the capacitor C4, and the control end of the switch 142 is coupled to the control end of the switch 141 to be in accordance with the second control signal V2. And the switch 142 is turned on or off. The input end of the buffer 143 is coupled to the second end of the capacitor C3, and the output end of the buffer 143 outputs the first coupling voltage. The input end of the buffer 144 is coupled to the second end of the capacitor C4, and the output end of the buffer 144 outputs a second coupling voltage.

In this embodiment, during the enable period of the second control signal V2, the switch 141 and the switch 142 are simultaneously turned on, so that the capacitor C3 couples the common voltage Vcom, the touch voltage VT1 and the average voltage to generate the first coupling voltage and The capacitor C4 is coupled to the common voltage Vcom, the reset voltage VR1, and the average voltage to generate a second coupling voltage.

In addition, the touch device 100 of the embodiment further includes a switch 160. The first end of the switch 160 is coupled to the contact capacitor CT1, the second end of the switch 160 is coupled to the ground, and the control end of the switch 160 is controlled by the reset signal Vreset1. Wherein, during the enable period of the reset signal Vreset1, the switch 160 is turned on to discharge the voltage of the touch capacitor CT1 via the switch 160. And the switch 160 includes a transistor M1. The 汲 terminal of the transistor M1 is coupled to the contact capacitor CT1. The gate terminal of the transistor M1 is coupled to receive the reset signal Vreset1, and the source terminal of the transistor M1 is coupled to the ground.

In addition, the touch control unit 110 of the embodiment further includes an analog digital converter 150. The analog-to-digital converter 150 is coupled to the signal processing unit 140 for receiving the first coupling voltage and the second coupling voltage, and performing analog-digital conversion on the first coupling voltage and the second coupling voltage to output the first digital signal and the second Digital signal. Then, the first digital signal and the second digital signal are transmitted to the back end circuit for subsequent processing, thereby reflecting the related information of the touch device 100 touched by the user.

The detailed circuit of the touch device 100 of the present embodiment and its coupling relationship and related operations have been generally described. Hereinafter, the operation of the touch device 100 will be described with a timing chart of the signal.

2 is a timing diagram of the sampling signal SS1, the charge reset signal SR1, the equalization signal VC1, the first control signal V1, and the second control signal V2 according to an embodiment of the present invention. Referring to FIG. 1 and FIG. 2 together, firstly, when the user presses the touch device 100, the touch device 100 converts the message pressed by the user into a voltage and stores it on the touch capacitor CT1. Then, the touch device 100 enables the sampling signal SS1 to turn on the switch 121, and the capacitor C1_1 samples and saves the voltage on the touch capacitor CT1 to generate the touch voltage VT1.

After that, the touch device 100 enables the reset signal Vreset1, so that the transistor M1 of the switch 160 is turned on, and the voltage on the touch capacitor CT1 is discharged to the ground voltage level via the transistor M1, so as to make the touch capacitor The CT1 can store the voltage that is converted when the user presses the touch device 100 next time. Then, the touch device 100 enables the charge reset signal SR1 to turn on the switch 122, and the capacitor C2_1 samples and saves the voltage on the touch capacitor CT1 to generate the reset voltage VR1.

Then, the touch control device 100 enables the first control signal V1, so that the switches 131 and 132 are turned on, and the touch voltage VT1 and the reset voltage VR1 are transmitted via the switch unit 130. On the other hand, during the sub-energy period T1 of the first control signal V1, the touch device 100 enables the second control signal V2, so that the switches 141 and 142 are turned on, and the second ends of the capacitors C3 and C4 receive the common voltage. Vcom, and capacitor C3 first couples touch voltage VT and common voltage Vcom to generate voltage VT1+Vcom, and capacitor C4 first couples reset voltage VR1 and common voltage Vcom to generate voltage VR1+Vcom. Then, during the sub-energy period T2 of the first control signal V1, the touch device 100 enables the equalization of the signal VC1, so that the switch 123 is turned on, and the charge sharing effect occurs between the touch voltage VT1 and the reset voltage VR1 to generate a charge sharing effect. The average voltage of the touch voltage VT1 and the reset voltage VR1 ((VT1+VR1)/2).

Since switches 131 and 132 are still conducting, the average voltage is transferred to capacitors C3 and C4 via buffer 124 and switch 131 and buffer 125 and switch 132, respectively. Next, capacitor C3 couples voltage VT1+Vcom to the average voltage (VT1+VR1)/2 to produce a first coupling voltage, ie VT1+Vcom-(VT1+VR1)/2=Vcom+(VT1-VR1)/2 Capacitor C4 couples voltage VR1+Vcom to the average voltage (VT1+VR1)/2 to produce a second coupling voltage, VR1+Vcom-(VT1+VR1)/2=Vcom+(VR1-VT1)/2. Thereafter, the first coupling voltage and the second coupling voltage are transmitted to the analog-to-digital converter 150 to perform analog-digital conversion on the first coupling voltage and the second coupling voltage to generate a first digital signal and a second digital signal. Next, the first digit signal and the second digit signal are transmitted to a back end circuit for corresponding subsequent processing. In this embodiment, since the first coupling voltage and the second coupling voltage are mutually opposite voltages, the noise during signal transmission can be effectively reduced. In addition, since the touch device 100 does not need to apply any resistance, the touch device 100 can be made/guaranteed with a low quiescent current.

In addition, in the embodiment, the touch device 100 further includes a touch capacitor CT2, and the touch control unit 110 further includes a signal sample holding unit 170 and a switch unit 180.

The signal sampling and holding unit 170 is coupled to the contact control capacitor CT2 for sampling and storing the voltage on the touch capacitor CT2 during the enabling of the sampling signal SS2 to generate the touch voltage VT2, and during the enabling of the charge reset signal SR2. The voltage on the touch capacitor CT2 is sampled and saved to generate a reset voltage VR2. The signal sampling and holding unit 170 further generates an average voltage of the touch voltage VT2 and the reset voltage VR2 according to the equalization signal VC2. The switch unit 180 is coupled to the signal sample storage unit 170 for receiving and transmitting the touch voltage VT2, the reset voltage VR2, and the average voltage to the signal processing unit 140 according to the third control signal V3. The signal processing unit 140 receives the touch voltage VT2, the reset voltage VR2, and the average voltage, and couples the touch voltage VT2, the reset voltage VR2, the average voltage, and the common voltage Vcom according to the second control signal V2 to generate The third coupling voltage is the fourth coupling voltage. The third coupling voltage and the fourth coupling voltage are transmitted to the analog digital conversion circuit 150 for analog digital conversion to generate a third digital signal and a fourth digital signal, and then perform corresponding subsequent processing.

In addition, the operation manners of the signal sampling and holding unit 170, the switch unit 180, and the switch 190 and the coupling relationship of the internal components thereof can be referred to the related descriptions of the signal sampling and holding unit 120, the switch unit 130, and the switch 160, and thus will not be described herein. In this way, in the case of the shared signal processing unit 140, the present embodiment can effectively reduce the noise during signal transmission between the signal sample holding units 170 and 180 to the signal processing unit 140, that is, reduce the juxtaposition to the serial ( Parallel to serial) the noise during processing, and the touch device 100 has a low static current.

In summary, the signal sampling and storage unit samples and saves the voltage on the touch capacitor to generate a touch voltage and sample and save the charge reset signal during the enablement of the charge reset signal. The voltage on the touch capacitor generates a reset voltage, and the average voltage of the touch voltage and the reset voltage is generated according to the equalization signal. Thereafter, the touch voltage, the reset voltage, and the average voltage are respectively transmitted to the signal processing unit through the switch unit. Then, the touch voltage, the reset voltage, the average voltage, and the common voltage are coupled by the signal processing unit to generate the first coupling voltage and the second coupling voltage. In this way, the noise during signal transmission and the low quiescent current of the touch device can be effectively reduced. In addition, in the case of the shared signal processing unit, the embodiment of the present invention can effectively reduce the noise during signal transmission between the plurality of signal sampling and holding units to the signal processing unit, that is, reduce the noise that is juxtaposed into the serial processing. And the touch device still has a low quiescent current.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100. . . Touch device

110. . . Touch control unit

120, 170. . . Signal sampling storage unit

130, 180. . . Switch unit

140. . . Signal processing unit

150. . . Analog digital converter

121~123, 131, 132, 141, 142, 160, 171~173, 181, 182, 190. . . switch

124, 125, 143, 144, 174, 175. . . buffer

CT1, CT2. . . Touch capacitor

C1_1~C1_2, C2_1~C2_2, C3, C4. . . capacitance

M1, M2. . . Transistor

SS1, SS2. . . Sampling signal

SR1, SR2. . . Charge reset signal

V1~V3. . . First to third control signals

VC1, VC2. . . Equalization signal

Vreset1, Vreset2. . . Reset signal

VT1, VT2. . . Touch voltage

VR1, VR2. . . Reset voltage

Vcom. . . Shared voltage

T1, T2. . . Sub-energy period of the first control signal

The following drawings are a part of the specification of the invention, and illustrate the embodiments of the invention

FIG. 1 is a schematic diagram of a touch device according to an embodiment of the invention.

2 is a timing diagram of a sampling signal, a charge reset signal, an equalization signal, a first control signal, and a second control signal according to an embodiment of the present invention.

100. . . Touch device

110. . . Touch control unit

120, 170. . . Signal sampling storage unit

130, 180. . . Switch unit

140. . . Signal processing unit

150. . . Analog digital converter

121~123, 131, 132, 141, 142, 160, 171~173, 181, 182, 190. . . switch

124, 125, 143, 144, 174, 175. . . buffer

CT1, CT2. . . Touch capacitor

C1_1~C1_2, C2_1~C2_2, C3, C4. . . capacitance

M1, M2. . . Transistor

SS1, SS2. . . Sampling signal

SR1, SR2. . . Charge reset signal

V1~V3. . . First to third control signals

VC1, VC2. . . Equalization signal

Vreset1, Vreset2. . . Reset signal

VT1, VT2. . . Touch voltage

VR1, VR2. . . Reset voltage

Vcom. . . Shared voltage

Claims (8)

A touch device has a touch capacitor, and the touch device includes: a touch control unit, comprising: a signal sampling and holding unit coupled to the touch capacitor for sampling during the enable of a sampling signal and The voltage on the touch capacitor is saved to generate a touch voltage, and a voltage on the touch capacitor is sampled and stored during a charge reset signal to generate a reset voltage. The signal storage unit is further based on An equalizing signal is used to generate an average voltage of the touch voltage and the reset voltage; a switching unit coupled to the signal sampling and holding unit for receiving and transmitting the touch voltage according to a first control signal, a reset voltage and the average voltage; and a signal processing unit coupled to the switch unit for receiving the touch voltage, the reset voltage, the average voltage, and a common voltage, and according to a second control signal, The touch voltage, the reset voltage, and the average voltage are coupled to the common voltage to generate a first coupling voltage and a second coupling voltage. The touch device of claim 1, wherein the signal sampling and holding unit comprises: a first switch, wherein the first end receives the touch voltage, and the control end is controlled by a sampling signal to determine the The first switch is connected to or disconnected from the first switch; the first end is coupled to the second end of the first switch, the second end is coupled to the ground end for holding the touch voltage; and the second switch is The first end receives the reset voltage, the control end is controlled by a charge reset signal to determine whether the second switch is turned on or off; and the second capacitor has a first end coupled to the second end of the second switch The second end is coupled to the ground end for storing the reset voltage. The third switch has a first end coupled to the first end of the first capacitor, and a second end coupled to the second capacitor a first end, the control end is controlled by the equalization signal, so that the first end of the first capacitor and the first end of the second capacitor are coupled to each other to generate the average voltage; a first buffer, coupled Connected to the first end of the first capacitor for receiving and outputting the touch voltage and the average voltage; The second buffer is coupled to the first end of the second capacitor for receiving and outputting the reset voltage and the average voltage. The touch device of claim 1, wherein the switch unit comprises: a fourth switch, the first end of which is coupled to the signal sampling and holding unit, the second end of which is coupled to the signal processing unit, and the control thereof The end is controlled by the first control signal, and determines that the fourth switch is turned on and off to transmit the touch voltage and the average voltage; and a fifth switch, the first end of which is coupled to the signal sampling and holding unit, The second end is coupled to the signal processing unit, and the control end is controlled by the first control signal, and determines that the fifth switch is turned on or off to transmit the reset voltage and the average voltage. The touch device of claim 1, wherein the signal processing unit comprises: a third capacitor, the first end receiving the touch voltage and the average voltage; and a fourth capacitor receiving the first end a reset voltage and the average voltage; a sixth switch having a first end coupled to the second end of the third capacitor, a second end receiving the common voltage, and a control end controlled by the second control signal, The second switch is connected to the second end of the sixth switch, the second end of the seventh switch is coupled to the second end of the fourth capacitor, and the control end is coupled Connecting the control end of the sixth switch to determine whether the seventh switch is turned on or off according to the second control signal; a third buffer having an input end coupled to the second end of the third capacitor, and an output end thereof And outputting the first coupling voltage; and a fourth buffer having an input end coupled to the second end of the fourth capacitor, the output end outputting the second coupling voltage, wherein during the enabling of the second control signal The sixth switch is electrically connected to the seventh switch, so that the third Capacitively coupling the common voltage, the touch voltage and the average voltage to generate the first coupling voltage and causing the fourth capacitor to couple the common voltage, the reset voltage and the average voltage to generate the second coupling voltage. The touch device of claim 1, further comprising: an eighth switch, the first end of which is coupled to the touch capacitor, the second end of which is coupled to the ground end, and the control end is controlled by a weight a signal, wherein an enable period of the reset signal is between an enable period of the sample signal and an enable period of the charge reset signal, and during an enable period of the reset signal, the eighth switch Turning on, the voltage on the touch capacitor is discharged through the eighth switch. The touch device of claim 5, wherein the eighth switch comprises: a transistor, wherein the gate is coupled to the touch capacitor, and the gate is coupled to receive the reset signal, and the source is coupled to the source. Ground terminal. The touch control device of claim 1, wherein the touch control unit further comprises: an analog-to-digital converter coupled to the signal processing unit for receiving the first coupling voltage and the second coupling voltage And performing analog-digital conversion on the first coupling voltage and the second coupling voltage to output a first digital signal and a second digital signal. The touch device of claim 1, wherein the touch control device further comprises a second touch capacitor, and the touch control unit further comprises: a second signal sample storage unit coupled to the second The touch capacitor is configured to sample and save the voltage on the second touch capacitor during the enable of the second sampling signal to generate a second touch voltage, and during the enable of the second charge reset signal Sampling and storing the voltage on the second touch capacitor to generate a second reset voltage, the second signal sampling and holding unit further generating the second touch voltage and the second reset according to a second equalization signal a second average voltage of the voltage; and a second switching unit coupled to the second signal sampling and holding unit and the signal processing unit for receiving and transmitting the second touch voltage according to a third control signal, a second reset voltage and the second average voltage, wherein the signal processing unit receives the second touch voltage, the second reset voltage, and the second average voltage, and according to the second control signal, the second Two touch voltages, the first The second reset voltage, the second average voltage is coupled to the common voltage to generate a third coupling voltage and a fourth coupling voltage.