CN-115167703-B - Touch driving device, touch control device and touch driving method

CN115167703BCN 115167703 BCN115167703 BCN 115167703BCN-115167703-B

Abstract

Provided are a touch driving device, a touch control device, and a touch driving method. The touch driving device is used for driving the mutual capacitance type touch panel. The touch driving device includes at least one output module and a controller. Each output module comprises at least two output stage circuits, and the output end of each output stage circuit is used for outputting a driving signal to a connected driving electrode. The touch driving method includes determining, for each output module, a first set of output stage circuits and a second set of output stage circuits at a current driving period according to a code division multiple access (CDM) code matrix, wherein a first set of driving signals at an output of the first set of output stage circuits are expected to discharge a first set of driving electrodes and a second set of driving signals at an output of the second set of output stage circuits are expected to charge a second set of driving electrodes, and controlling charging the second set of driving electrodes with power from the first set of driving electrodes in response to the determination.

Inventors

BRADY KEITH
Constantinos Theodoropoulos

Assignees

北京奕斯伟计算技术股份有限公司
北京奕斯伟计算技术股份有限公司

Dates

Publication Date: 20260421
Application Date: 20220628
Priority Date: 20220628

Claims (15)

1. A touch driving device for a touch sensor, wherein the touch sensor includes a plurality of driving electrodes and a plurality of sensing electrodes disposed to cross each other, the touch driving device comprising: at least one output module, each output module comprises at least two output stage circuits, and the output end of each output stage circuit is used for outputting a driving signal to a connected driving electrode; A controller configured to, for each output module, Determining a first set of output stage circuits and a second set of output stage circuits for a current drive period based on a code division multiple access CDM code matrix, wherein a first set of drive signals at the outputs of the first set of output stage circuits are expected to discharge the first set of drive electrodes and a second set of drive signals at the outputs of the second set of output stage circuits are expected to charge the second set of drive electrodes, and In response to the determination, controlling to charge the second set of drive electrodes with power from the first set of drive electrodes for a first period of time, The touch driving device further includes at least one comparing unit, wherein: Each comparing unit compares one of a first set of voltage values at an output of the first set of output stage circuits with a corresponding one of a second set of voltage values at an output of the second set of output stage circuits and outputs a comparison result indicating whether a voltage difference of the one of the first set of voltage values and the corresponding one of the second set of voltage values satisfies a threshold condition, wherein the controller determines that the first period of time ends when a number of comparison results indicating that the threshold condition is satisfied is equal to or greater than a first predetermined number.
2. The touch drive of claim 1, wherein the controller controls the first and second sets of output stage circuits to: Charging the second set of drive electrodes with power from the first set of drive electrodes for the first period of time, and After the first period of time has elapsed, the remaining power from the first set of drive electrodes is discharged to a low-level power supply terminal, and the second set of drive electrodes is charged with a high-level power supply terminal.
3. The touch driving device of claim 2, further comprising at least one path switch disposed between the output terminals of each of the at least two output stage circuits, Wherein during the first period of time, the controller disables the first set of output stage circuits and the second set of output stage circuits and controls turning on at least a portion of the at least one path switch such that power from the first set of drive electrodes charges the second set of drive electrodes, and After the first period of time has elapsed, the controller enables a conduction path between the output terminals of the first set of output stage circuits and the low level power supply terminal and a conduction path between the high level power supply terminal and the output terminals of the second set of output stage circuits and controls the turning off of the at least a portion of the at least one path switch.
4. The touch driving device according to claim 3, further comprising at least one charge share bus, Wherein the output terminal of each of the at least two output stage circuits is connected to the at least one charge share bus via a corresponding path switch, and each path switch is a single bidirectional conduction switch or a pair of unidirectional conduction switches with opposite conduction directions.
5. A touch driving device according to claim 3, wherein the output terminals of each two output stage circuits are connected to two input terminals of one comparing unit, respectively, Wherein the controller determines the enabled comparison unit based on the determined conductive path switch.
6. The touch driving apparatus of claim 1, wherein the comparing unit comprises a scaling subunit for scaling the voltage value of the first input of the comparing unit to compare the scaled voltage value with the voltage value of the second input.
7. A touch driving device according to claim 2 or 3, wherein each output stage circuit comprises a first switch and a second switch connected in series between a high voltage power supply terminal and a low voltage power supply terminal, connection nodes of the first switch and the second switch being connected to output terminals of the output stage circuit, The controller turns off the first switch and the second switch of each of the first set of output stage circuits and the second set of output stage circuits during the first period of time, and The controller turns on a first switch of each output stage circuit of the second group of output stage circuits to charge the driving electrode via the first switch with a high-level power supply terminal, and turns off a second switch of each output stage circuit of the first group of output stage circuits to discharge the remaining power of the driving electrode to a low-level power supply terminal via the second switch after the first period of time has elapsed.
8. The touch driving apparatus of claim 1, wherein the controller determines the desired driving signal corresponding to each driving electrode according to the CDM code matrix, wherein each desired driving signal comprises a plurality of driving periods, wherein a duration of each driving period is half of a period of the desired driving signal, For each drive period, the controller determines the first set of output stage circuits and the second set of output stage circuits based on the determined desired drive signal.
9. The touch driving apparatus according to claim 1, wherein the at least one output module is plural in number, and Each output module is connected to a set of drive electrodes, the number of which is the same as the number of output stage circuits included in the output module.
10. A touch driving device for a touch sensor, wherein the touch sensor includes a plurality of driving electrodes and a plurality of sensing electrodes disposed to cross each other, the touch driving device comprising: at least one output module, each output module comprises at least two output stage circuits, and the output end of each output stage circuit is used for outputting a driving signal to a connected driving electrode; A controller configured to, for each output module, Determining a first set of output stage circuits and a second set of output stage circuits for a current drive period based on a code division multiple access CDM code matrix, wherein a first set of drive signals at the outputs of the first set of output stage circuits are expected to discharge the first set of drive electrodes and a second set of drive signals at the outputs of the second set of output stage circuits are expected to charge the second set of drive electrodes, and In response to the determination, controlling to charge the second set of drive electrodes with power from the first set of drive electrodes for a first period of time, Wherein the touch driving device further comprises at least one charge sharing bus, wherein an output terminal of each of the at least two output stage circuits is connected to the at least one charge sharing bus via a corresponding path switch, Wherein the touch driving device further comprises at least one comparing unit, wherein: A first input end of each comparison unit is connected with the output end of a first representative output stage circuit in the first group of output stage circuits to acquire a first representative voltage value, a second input end of each comparison unit is connected with the output end of a second representative output stage circuit in the second group of output stage circuits to acquire a second representative voltage value to acquire at least one comparison result, and the controller determines that the first time period is finished when the number of comparison results indicating that the acquired first representative voltage value and the corresponding second representative voltage value meet the threshold value condition is more than or equal to a second preset number, or The at least one comparison unit corresponds to the at least one charging shared bus one by one, a first end of each comparison unit is connected with the corresponding charging shared bus to obtain a bus voltage value, a second end of each comparison unit obtains a reference voltage value to obtain at least one comparison result, and the reference voltage value is related to the number of output stage circuits included in the first group of output stage circuits and the second group of output stage circuits; the controller determines that the first period of time ends when a number of comparison results indicating that a bus voltage value acquired from a corresponding charge sharing bus and the reference voltage value satisfy a threshold condition is equal to or greater than a third predetermined number.
11. A touch device, comprising: the touch panel comprises a plurality of driving electrodes and a plurality of sensing electrodes which are arranged in a crossing manner; The touch driving device according to any one of claims 1 to 10, configured to provide a driving signal to driving electrodes on the touch panel.
12. A touch driving method for a touch sensor including a plurality of driving electrodes and a plurality of sensing electrodes disposed to cross each other, the plurality of driving electrodes being divided into at least one group, each group corresponding to one output module, each output module including the same number of output stage circuits as the driving electrodes of each group, The method comprises for each of the output modules, Determining a first set of output stage circuits and a second set of output stage circuits for a current drive period based on a code division multiple access CDM code matrix, wherein a first set of drive signals at the outputs of the first set of output stage circuits are expected to discharge the first set of drive electrodes and a second set of drive signals at the outputs of the second set of output stage circuits are expected to charge the second set of drive electrodes, and In response to the determination, controlling to charge the second set of drive electrodes with power from the first set of drive electrodes for a first period of time, The touch driving method further comprises the following steps: One of a first set of voltage values at the output of the first set of output stage circuits is compared with a corresponding one of a second set of voltage values at the output of the second set of output stage circuits, and a comparison result is output indicating whether a voltage difference of the one of the first set of voltage values and the corresponding one of the second set of voltage values satisfies a threshold condition, and the first period of time is determined to end when the number of comparison results indicating that the threshold condition is satisfied is equal to or greater than a first predetermined number.
13. The touch driving method according to claim 12, further comprising: After the first period of time passes, controlling to release the remaining power from the first set of driving electrodes to a low level power supply terminal and continuing to charge the second set of driving electrodes with a high level power supply terminal.
14. The touch driving method of claim 12, wherein at least one path switch is provided between output terminals of every two output stage circuits among the output stage circuits included in each output module, Wherein controlling charging the second set of drive electrodes with power from the first set of drive electrodes further comprises: Disabling the first and second sets of output stage circuits and controlling conduction of at least a portion of the at least one path switch during the first period of time such that power from the first set of drive electrodes charges the second set of drive electrodes, and After the first period of time has elapsed, enabling a conduction path between the output terminals of the first set of output stage circuits and the low level power supply terminal and a conduction path between the high level power supply terminal and the output terminals of the second set of output stage circuits, and controlling to turn off the at least a portion of the at least one path switch.
15. A touch driving method for a touch sensor including a plurality of driving electrodes and a plurality of sensing electrodes disposed to cross each other, the plurality of driving electrodes being divided into at least one group, each group corresponding to one output module, each output module including the same number of output stage circuits as the driving electrodes of each group, The method comprises for each of the output modules, Determining a first set of output stage circuits and a second set of output stage circuits for a current drive period based on a code division multiple access CDM code matrix, wherein a first set of drive signals at the outputs of the first set of output stage circuits are expected to discharge the first set of drive electrodes and a second set of drive signals at the outputs of the second set of output stage circuits are expected to charge the second set of drive electrodes, and In response to the determination, controlling to charge the second set of drive electrodes with power from the first set of drive electrodes for a first period of time, Wherein an output terminal of each output stage circuit in the output module is connected to at least one charge sharing bus via a corresponding path switch, and the touch driving method further comprises: Comparing a first representative voltage value at an output of a first representative output stage circuit of the first set of output stage circuits with a second representative voltage value at an output of a second representative output stage circuit of the second set of output stage circuits to obtain at least one comparison result, and determining that the first time period is over when the number of comparison results indicating that the acquired first representative voltage value and the corresponding one of the second representative voltage values satisfy a threshold condition is greater than or equal to a second predetermined number, or Comparing a bus voltage value on each charging shared bus with a reference voltage value to obtain at least one comparison result, wherein the reference voltage value is related to the number of output stage circuits included in the first group of output stage circuits and the second group of output stage circuits; and determining that the first time period is ended when the number of comparison results indicating that the bus voltage value on the corresponding charging shared bus and the reference voltage value meet the threshold condition is greater than or equal to a third preset number.

Description

Touch driving device, touch control device and touch driving method Technical Field The present application relates to the field of touch control, and more particularly, to a touch driving device, a touch device, and a touch driving method. Background In recent years, a touch device including what is called a so-called touch panel capable of detecting an external proximity object has been attracting attention. The touch panel is mounted on or integrated with a display device such as a liquid crystal display device or an OLED display device, for example, and thus is used as a touch display device with a touch detection function. The touch panel may be provided with a touch sensor, such as a projected capacitive touch sensor. The touch sensor may implement a mutual capacitance or a self-capacitance sensing mode of operation. In a mutual capacitance implementation or mode of operation, a touch sensor may include an array of drive and sense electrodes forming an array of capacitive nodes. The overlapping regions of the drive and sense electrodes may form capacitive nodes, and the drive and sense electrodes may be capacitively coupled to each other across the space therebetween. The drive signals applied to the drive electrodes (TX) by the touch control circuitry (control circuitry for touch detection) may induce charge on the sense electrodes based on the coupled mutual capacitance, and the induced charge amount may be susceptible to external influences (e.g., touch or proximity of an object). The touch control circuit provides touch sensing signals to a processing device (e.g., CPU, etc.) for the processing device to determine the location or proximity of a touch within the touch sensitive area of the touch sensor by measuring the change in capacitance of the mutual capacitance array across the entire drive-sense electrode. In the case of a touch display device or a touch display device with a fingerprint recognition function, the processing device may also interact with a display driving circuit and/or a fingerprint recognition control circuit or the like to control the display operation and the fingerprint recognition operation. Aiming at the touch detection process of the touch panel, low noise and low power consumption can be realized as much as possible, so that the detection precision is improved, the power consumption cost is reduced, and the method is a target pursued by the industry. Disclosure of Invention The application aims to provide a touch driving device and a touch driving method, thereby achieving the purposes of low noise and low power consumption in the touch detection process. According to an aspect of the present application, there is provided a touch driving apparatus for a touch sensor, wherein the touch sensor includes a plurality of driving electrodes and a plurality of sensing electrodes arranged to cross, the touch driving apparatus including at least one output module, each output module including at least two output stage circuits, an output terminal of each output stage circuit for outputting a driving signal to a connected driving electrode, a controller configured to determine, for each output module, a first set of output stage circuits and a second set of output stage circuits at a current driving period according to a code division multiple access (CDM) code matrix, wherein the first set of driving signals at the output terminal of the first set of output stage circuits are expected to discharge the first set of driving electrodes and the second set of driving signals at the output terminal of the second set of output stage circuits are expected to charge the second set of driving electrodes, and to control charging the second set of driving electrodes with power from the first set of driving electrodes in response to the determination. According to an aspect of the present application, there is provided a touch device including a touch panel including a plurality of driving electrodes and a plurality of sensing electrodes arranged to cross, and a touch driving device as described above configured to provide driving signals to the driving electrodes on the touch panel. According to a further aspect of the present application there is provided a touch driving method for a touch sensor comprising a plurality of driving electrodes and a plurality of sensing electrodes arranged alternately, the plurality of driving electrodes being divided into at least one group, each group corresponding to an output module, each output module comprising the same number of driving electrodes as each group, the method comprising determining, for each output module, a first group of output stage circuits and a second group of output stage circuits at a current driving period according to a code division multiple access (CDM) code matrix, wherein a first group of driving signals at the outputs of the first group of output stage circuits are expected to discharge the first group of driving electrod