Touch sensing device and method thereof

• US 8,872,791 B2
• Filed: 12/22/2011
• Issued: 10/28/2014
• Est. Priority Date: 10/21/2011
• Status: Expired due to Fees

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: Kwon, Yong Il, Lee, Hyun Suk, Park, Tah Joon
• Primary Examiner(s): Chang, Kent
• Assistant Examiner(s): Hagemeier, Herbert L
• Application Number:
  US13/334,405
• Publication Number:
  US 20130100069A1
• Time in Patent Office: 1,041 Days
• Field of Search: 345156-174, 324/658, 324/679, 341/20, 341/143
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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

There are provided a touch sensing device and a method thereof. The touch sensing device, including: a plurality of sensing circuit units measuring capacitance variations from a plurality of sensing electrodes; at least one TDC circuit connected with the plurality of sensing circuit units to convert the capacitance variations into digital signals; a calculating unit judging a touch from the digital signals; and a delay circuit sequentially receiving the capacitance variations from the plurality of sensing circuit units.

Claims

1. A touch sensing device, comprising:

a plurality of sensing circuit units to measure capacitance variations from a plurality of sensing electrodes;

at least one time-to-digital converter (TDC) circuit to sequentially receive the capacitance variations from the plurality of sensing circuit units to generate digital signals by measuring a time required for a voltage signal corresponding to a capacitance variation of the capacitance variations to be varied to have a predetermined reference voltage;

a calculating unit to judge a touch from the digital signals;

a delay circuit to control, using a plurality of predetermined delay time periods, individual circuit units of the plurality of sensing circuit units to detect the capacitance variations during different respective time periods,

wherein a first of the plurality of predetermined delay time periods partialy overlaps a second of the plurality of predetermined delay time periods, and

wherein a time period length of each of the the plurality of predetermined delay time periods is based on a time required for the at least one TDC circuit to generate the digital signals and a time difference between a minimum time and a maximum time required for the voltage signal to be varied to have the predetermined reference voltage; and

a switching circuit to control connections between the plurality of sensing circuit units and the at least one TDC circuit in synchronization with the plurality of predetermined delay time periods.

2. The touch sensing device of claim 1, wherein the delay circuit sets different delay times for the plurality of individual sensing circuit units.

3. The touch sensing device of claim 1, wherein the plurality of sensing circuit units measure mutual-capacitance variations generated among the plurality of sensing electrodes.

4. The touch sensing device of claim 1, further comprising a panel section in which a plurality of sensing electrodes, electrically connected with the plurality of sensing circuit units, are provided.

5. The touch sensing device of claim 1, wherein the switching circuit controlling connections between the plurality of sensing circuit units and the TDC circuit, in accordance with the delay times set for the plurality of individual sensing circuit units.

6. The touch sensing device of claim 1, wherein the calculating unit judges the touch by using a weighted average of the digital signals.

7. A touch sensing method, comprising:

measuring, using a plurality of sensing circuit units, a plurality of capacitance variations at different respective times from a plurality of sensing electrodes;

generating digital signals by sequentially receiving, using a time-to-digital converter (TDC), the plurality of capacitance variations; and

judging a touch based on the generated digital signals,

controlling, using a plurality of predetermined delay time periods, individual circuit units of the plurality of sensing circuit units to detect the capacitance variations during different respective time periods,

wherein a first of the plurality of predetermined delay time periods partialy overlaps a second of the plurality of predetermined delay time periods, and

wherein a time period length of each of the the plurality of predetermined delay time periods is based on a time required for the at least one TDC circuit to generate the digital signals and a time difference between a minimum time and a maximum time required for the voltage signal to be varied to have the predetermined reference voltage; and

controlling, using a switching circuit, connections between the plurality of sensing circuit units and the at least one TDC circuit in synchronization with the plurality of predetermined delay time periods.

8. The touch sensing method of claim 7, wherein the delay times are differentially applied to the plurality of sensing electrodes.