Scanning circuit for touch screen, touch screen and touch control method

Patent metadata

Field	Value
Publication number	US-10545606-B2
Application number	US-201715736397-A
Country	US
Kind code	B2
Filing date	May 5, 2017
Priority date	Jun 30, 2016
Publication date	Jan 28, 2020
Grant date	Jan 28, 2020

Abstract

The present disclosure discloses a scanning circuit for touch screen, touch screen and touch control method. The canning circuit for touch screen includes: a multiplexing circuit and a touch driving circuit coupled to the same, the touch driving circuit includes m signal input terminals, each of which is coupled to n receiving-electrode channels, and in an ith time slot of a current scanning period, the multiplexing circuit controls the touch driving circuit to receive, through the m signal input terminals, output signals from m receiving-electrode channels, and determines a touch position according to an emitting-electrode channel corresponding to the current scanning period and the output signals of the m receiving-electrode channels, the current scanning period includes n time slots, i=1, 2, . . . n, and the output signals of the m receiving-electrode channels received by the touch driving circuit in each time slot are different.

First claim

What is claimed is:

1. A scanning circuit for a touch screen comprising a touch panel, the touch panel comprising a plurality of emitting-electrode channels, each of which comprises a plurality of emitting touch sensing electrodes connected in series, and a plurality of receiving-electrode channels, each of which comprises a plurality of receiving touch sensing electrodes connected in series, the scanning circuit comprising: a multiplexing circuit and a touch driving circuit coupled to the multiplexing circuit,
wherein the touch driving circuit comprises m signal input terminals, and each of the m signal input terminals is coupled to n receiving-electrode channels of the plurality of receiving-electrode channels, where both m and n are integers greater than or equal to 2, and
the multiplexing circuit is configured to, in an i th time slot of a current scanning period of the touch panel, control the touch driving circuit to receive, through the m signal input terminals, output signals from m receiving-electrode channels of the plurality of receiving-electrode channels, and to determine a touch position according to the emitting-electrode channel corresponding to the current scanning period and the output signals of the m receiving-electrode channels,
wherein the current scanning period comprises n time slots, where i=1, 2, . . . n, and the output signals of the m receiving-electrode channels received by the touch driving circuit in each of the time slots are different.

2. The scanning circuit for a touch screen according to claim 1 , comprising: M transistors, wherein M=m*n, and the multiplexing circuit comprises n signal output terminals,
each of the n signal output terminals is coupled to gates of m transistors, first terminals of the m transistors are coupled to the m signal input terminals respectively, and second terminals of the m transistors are coupled to the m receiving-electrode channels in the touch panel respectively,
the multiplexing circuit is configured to, in the i th time slot of the current scanning period, output a high-level signal from an i th signal output terminal, and to output low-level signals from the remaining n−1 signal output terminals, so as to control the m transistors connected to the i th signal output terminal to be turned on, and
the touch driving circuit is configured to receive, in the i th time slot, the output signals of the m receiving-electrode channels respectively coupled to the m transistors which are turned on.

3. The scanning circuit for a touch screen according to claim 2 , wherein the multiplexing circuit comprises n multiplexing sub-circuits, each of the n multiplexing sub-circuits comprises a signal output terminal coupled to the gates of the m transistors; and in the i th time slot of the current scanning period, an i th multiplexing sub-circuit in the multiplexing circuit outputs a high-level signal, and remaining n−1 multiplexing sub-circuits output low-level signals.

4. The scanning circuit for a touch screen according to claim 3 , wherein,
each of the n multiplexing sub-circuits comprises the signal output terminal, an input terminal, a reset terminal, a low voltage level terminal, a first clock signal terminal, and a second clock signal terminal,
a first clock signal terminal, a second clock signal terminal, an input terminal and a low voltage level terminal of a first multiplexing sub-circuit are coupled to a first clock signal line, a second clock signal line, a third clock signal line, and a low voltage level line respectively, a signal output terminal of the first multiplexing sub-circuit is coupled to an input terminal of a second multiplexing sub-circuit, and a reset terminal of the first multiplexing sub-circuit is coupled to a signal output terminal of the second multiplexing sub-circuit,
a first clock signal terminal, a second clock signal terminal and a low voltage level terminal of an i th multiplexing sub-circuit are coupled to the first clock signal line, the second clock signal-line and the low voltage level line respectively, an input terminal of the i th multiplexing sub-circuit is coupled to a signal output terminal of an (i−1) th multiplexing sub-circuit, and a reset terminal of the i th multiplexing sub-circuit is coupled to a signal output terminal of an (i+1) th multiplexing sub-circuit, and
a first clock signal terminal, a second clock signal terminal and a low voltage level terminal of an m th multiplexing sub-circuit are coupled to the first clock signal line, the second clock signal line and the low voltage level line respectively, an input terminal of the m th multiplexing sub-circuit is coupled to a signal output terminal of an (m−1) th multiplexing sub-circuit, and a reset terminal of the m th multiplexing sub-circuit is coupled to an external reset signal terminal.

5. The scanning circuit for a touch screen according to claim 4 , wherein the i th multiplexing sub-circuit comprises a first control circuit and a second control circuit, the first control circuit is coupled to the first clock signal terminal, the second clock signal terminal, the input terminal, and the signal output terminal of the i th multiplexing sub-circuit, and the second control circuit is coupled to the signal output terminal, the reset terminal and the low voltage level terminal of the i th multiplexing sub-circuit,
the first control circuit is configured to, in an (i−1) th time slot, receive a low-level first clock signal, a high-level second clock signal and a high-level third clock signal through the first clock signal terminal, the second clock signal terminal and the input terminal, and to output a low-level signal from the signal output terminal under the control of the low-level first clock signal, the high-level second clock signal, and the high-level third clock signal; and is configured to, in the i th time slot, receive a high-level first clock signal through the first clock signal terminal, and to output a high-level signal from the signal output terminal under the control of the high-level first clock signal, and
the second control circuit is configured to, in an (i+1) th time slot, receive a low-level signal and a high-level reset signal through the low-voltage level terminal and the reset terminal respectively, and to output a low-level signal from the signal output terminal under the low-level signal and the high-level reset signal.

6. The scanning circuit for a touch screen according to claim 5 , wherein the first control circuit comprises a first transistor, a second transistor, a first capacitor and a second capacitor,
a gate and a first terminal of the first transistor are coupled to the input terminal of the i th multiplexing sub-circuit, and a second terminal of the first transistor is coupled to the second control circuit, a gate of the second transistor, and one terminal of the first capacitor and one terminal of the second capacitor,
a first terminal of the second transistor is coupled to the first signal clock terminal of the i th multiplexing sub-circuit, and a second terminal of the second transistor is coupled to the other terminal of the first capacitor and the signal output terminal of the i th multiplexing sub-circuit, and the other terminal of the second capacitor is coupled to the second clock signal terminal of the i th multiplexing sub-circuit,
in the (i−1 ) th time slot, under the control of the low-level first clock signal received at the first clock signal terminal, the high-level second clock signal received at the second clock signal terminal, and the high-level third clock signal received at the input terminal, the first transistor and the second transistor are turned on, the first capacitor is charged, and the low-level first clock signal received at the first clock signal te

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Display Tech Co
• Beijing Boe Display Tech Group Co Ltd

Inventors

• Zhang Kan
• Zhang Bin
• Zhang Qiang
• Wang Guangxing
• Dong Dianzheng
• Chen Pengming

Classifications

• G06F3/0416 Primary

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/04166 Primary

  Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving (Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184) · CPC title