Touch sensing device with noise effect reduction

• US 10,185,447 B2
• Filed: 10/06/2015
• Issued: 01/22/2019
• Est. Priority Date: 04/22/2015
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Lin, Feng-Sheng, Lai, Chun-Chi, Wang, Tsang-Hong
• Primary Examiner(s): Blancha, Jonathan
• Application Number:
  US14/876,132
• Publication Number:
  US 20160313845A1
• Time in Patent Office: 1,204 Days
• CPC Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A touch sensing device includes a base panel, a plurality of receiving channels, at least one noise listening channel and at least one processing unit. The receiving channels are disposed on the base board in parallel. The at least one noise listening channel and the receiving channels are disposed on the base board in parallel. The processing unit is configured to generate touching sensing data according to a sensing signal outputted by a corresponding receiving channel of the plurality of receiving channels and a noise listening signal outputted by the at least one noise listening channel.

Claims

1. A touch sensing device, comprising:

at least one receiving channel, configured to output a first sensing signal and a first noise listening signal alternately;

at least one second receiving channel, configured to output a second sensing and a second noise listening signal alternately; and

at least one processing unit, configured to generate touch sensing data according to the first sensing signal, the second sensing signal, the first noise listening signal and the second noise listening signal,

wherein the first sensing signal and the second noise listening signal are sensed at a same first time duration and transmitted to the at least one processing unit during a same second time duration, and the second sensing signal and the first noise listening signal are sensed at a same third time duration and transmitted to the at least one processing unit during a same fourth time duration,

wherein the at least one processing unit further comprises;

a first receiving module; and

a first switching module, electrically connected to the at least one first receiving channel, the at least one second receiving channel and the first receiving module, the first switching module configured to transmit the first sensing signal and the second noise listening signal to the first receiving module during a first time interval;

the first switching module further configured to transmit the second sensing signal and the first noise listening signal to the first receiving module during a second time interval,

wherein the first receiving module outputs a first analog signal according to the first sensing signal and the second noise listening signal during the first time interval, and the first receiving module outputs the first analog signal according to the second sensing signal and the first noise listening signal during the second time interval, and the at least one processing unit further comprises;

a first analog-to-digital converter, electrically connected to the first receiving module, the first analog-to-digital converter configured to convert the first analog signal into a first digital signal; and

a first digital processing module, electrically connected to the first analog-to-digital converter, the first digital processing module configured to generate the touch sensing data according to the first digital signal.

2. The touch sensing device of claim 1, further comprising:

at least one first transmitting channel;

at least one second transmitting channel;

at least one first coupling capacitor; and

at least one second coupling capacitor;

wherein the at least one first transmitting channel is electrically connected to the at least one first receiving channel via the at least one first coupling capacitor, and the at least one second transmitting channel is electrically connected to the at least one second receiving channel via the at least one second coupling capacitor.

3. The touch sensing device of claim 2, wherein the at least one transmitting channel and the at least one second transmitting channel are spatially separated.

4. The touch sensing device of claim 2, wherein the at least one processing unit further comprises a transmitting module, the transmitting module is configured to transmit a first scanning signal to the at least one first transmitting channel, the at least one first receiving channel outputs the first sensing signal to the processing unit after the first scanning signal coupled to the at least one first coupling capacitor;

and the transmitting module is further configured to transmit a second scanning signal to the at least one second transmitting channel, the at least one second receiving channel outputs the second sensing signal to the at least one processing unit after the second scanning signal coupled to the at least one second coupling capacitor.

5. The touch sensing device of claim 4, wherein the transmitting module transmits the first scanning signal and the second scanning signal alternately.

6. The touch sensing device of claim 1, wherein the first receiving module comprises a first differential amplifier and a first feedback capacitor, a output terminal of the first differential amplifier is electrically connected to a first terminal of the first feedback capacitor to output the first analog signal, a first input terminal of the first differential is electrically connected to a second terminal of the first feedback capacitor;

the first input terminal of the first differential amplifier receives the first sensing signal, a second input terminal of the first differential amplifier receives the second noise listening signal during the first time interval;

the first input terminal of the first differential amplifier receives the second sensing signal, the second input terminal of the first differential amplifier receives the first noise listening signal during the second time interval.

7. The touch sensing device of claim 1, wherein the at least one processing unit further comprises:

a second receiving module, electrically connected to the at least one first receiving channel, the second receiving module configured to output a second analog signal according to the first sensing signal during a first time interval, and to output the second analog signal according to the first noise listening signal during a second time interval; and

a third receiving module, electrically connected to the at least one second receiving channel, the third receiving module configured to output a third analog signal according to the second noise listening signal during the first time interval, and to output the third analog signal according to the second sensing signal during the second time interval.

8. The touch sensing device of claim 1, wherein the at least one processing unit further comprises:

a second analog-to-digital converter, electrically connected to the second receiving module, the second analog-to-digital converter configured to convert the second analog signal into a second digital signal;

a third analog-to-digital converter, electrically connected to the third receiving module, the third receiving module configured to convert the third analog signal into a third digital signal; and

a second digital processing module, electrically connected to the second analog-to-digital converter and the third analog-to-digital converter, the second digital processing module configured to generate the touch sensing data according to the second digital signal and the third digital signal.