KR20160141259A - Finger sensor integrated type touch screen panel and driving method of the same - Google Patents

Abstract

The present invention relates to a touch screen having at least one finger&touch area and multiple touch areas in a display area. More specifically, the present invention relates to a finger sensor integrated touch screen apparatus which simplifies a circuit composition of a touch interated circuit (IC), and reduces the size of the touch IC and power consumption. The finger sensor integrated touch screen apparatus includes: a touch screen having at least one finger&touch area and multiple touch areas; finger&touch sensors; a sensing unit for common use; an analogue integration & amplifier; and an analogue-digital converter.

Description

Technical Field [0001] The present invention relates to a fingerprint sensor integrated touch screen device and a driving method thereof,

The present invention relates to a fingerprint sensor integrated touch screen device, and more particularly, to a touch screen device having a fingerprint recognition function.

With the development of computer technology, various applications such as a notebook computer, a tablet PC, a smart phone, a personal digital assistant, an automated teller machine, a search guide system, Computer based systems have been developed. Because these systems typically store a large amount of confidential data such as business information or business secrets, as well as personal information related to personal privacy, there is a need to enhance security to protect these data.

For this purpose, there has been known a fingerprint sensor capable of enhancing security by registering or authenticating a system using a fingerprint of a finger.

The fingerprint sensor is a sensor that detects a human fingerprint. The fingerprint sensor is roughly divided into an optical fingerprint sensor and a capacitive fingerprint sensor.

An optical fingerprint sensor uses a principle of irradiating a light source such as an LED (Light Emitting Diode) or the like and detecting light reflected by a ridge of a fingerprint through a CMOS image sensor. Since the optical fingerprint sensor needs to scan using LED, there is a limitation in reducing the size and a manufacturing cost is increased because the light source itself is expensive.

A capacitive fingerprint sensor utilizes a difference in the quantity of electricity charged between a ridge and a valley in contact with the fingerprint sensor.

A conventional capacitive fingerprint sensor is known as "capacitive sensor packaging ", US Patent Publication No. US2013 / 0307818 published on November 21, 2013. In the capacitive fingerprint sensor described in the above-mentioned U.S. Patent Application Publication, the capacitive fingerprint sensor is configured in the form of an assembly combined with a specific push button, and the electrostatic capacitance between the capacitive plate and the fingerprint (ridge and valley) A circuit for measuring capacitance includes a silicon wafer printed thereon.

Generally, ridges and valleys of human fingerprints are very small in size from about 300 μm to 500 μm. Therefore, the capacitive fingerprint sensor of the above-mentioned United States publication uses a high-resolution sensor array and an IC Integrated Chip) is required, and a silicon wafer that can form an integrated sensor array and IC is used. However, when a high-resolution sensor array and an IC are formed together using a silicon wafer, an assembly structure for combining a fingerprint sensor with a push button is required, which not only complicates the configuration but also increases the non-display area (bezel area) There was a problem. Further, since the push button (for example, the home key of the smart phone) and the fingerprint sensor are formed to overlap with each other, the thickness of the push button is increased, and the fingerprint sensing area is dependent on the size of the push button.

In order to solve such a problem, a technique of using the area of the touch sensor screen as a fingerprint identification area has been developed. US Patent No. 8,564, 314 entitled " Capacitive Touch Sensor for Identifying a Fingerprint ", entitled " Fingerprint Identification Integrated Capacitive Touch Screen Korean Patent No. 10-1432988, which was registered on Aug. 18, 2014, is known.

FIG. 1 is a plan view schematically showing an arrangement of a driving electrode and a sensing electrode of a capacitive sensing panel, which is shown in FIG.

1, the capacitive touch sensor for fingerprint identification includes a touch sensor 3 including a touch driving electrode 1 (x) and a touch sensing electrode 1 (y), a fingerprint driving electrode 5 (x ) And a fingerprint sensing electrode 5 (y). In this capacitive touch sensor for fingerprint identification, since a separate fingerprint sensor 5 is partially disposed in the screen area, there is a problem that the fingerprint sensor 5 area is not touched or the touch performance of the peripheral area is deteriorated there was.

Korean Patent Registration No. 10-1432988 discloses a fingerprint sensing mode in which a fingerprint is recognized using each of a plurality of microchannels and a plurality of microchannels are grouped in a touch sensing mode to touch a touch group channel for sensing a touch signal Discloses a technique for sensing a signal.

A sensing unit formed inside a touch IC typically senses an input signal using an operational amplifier and a sensing capacitor, and the sensing capacitor is determined according to the mutual capacitance of the sensing channels. Since the number of microchannels connected to one sensing unit is much larger at the time of touch sensing than at the time of fingerprint sensing, the capacitance of the sensing capacitor is much larger at the time of touch sensing than at the time of fingerprint sensing. In fact, the capacitance of the sensing capacitor required for touch sensing is several thousand times larger than the capacitance of the sensing capacitor required for fingerprint sensing. For this reason, the Korean registered patent should have a fingerprint sensing unit and a touch sensing sensing unit separately in the touch IC. In addition, since the touch sensing value is much larger than the fingerprint sensing value, the Korean registered patent discloses an analog-to-digital converter for digitally processing touch sensing data and an analog-to-digital converter for digitally processing fingerprint sensing data, Should be provided. Since the difference between the touch sensing value and the fingerprint sensing value is too large, the analog-to-digital converter digitally processes both the touch sensing value and the fingerprint sensing value with the same analog-to-digital converter There is no number. In the conventional technique, the touch sensing value is digitally processed by a first analog-to-digital converter having a first sensing range, and the fingerprint sensing value is digitally processed by a second analog-to-digital converter having a second sensing range smaller than the first sensing range I can not help it. The sensing unit and the digital-to-analog converter have a large circuit size.

If a fingerprint sensing sensing unit and a touch sensing sensing unit are separately provided in the touch IC as in the prior art and further an analog-to-digital converter for fingerprint sensing and an analog-to-digital converter for touch sensing are separately provided in the touch IC, Circuit structure of the touch IC becomes complicated, and the size and power consumption of the touch IC increase.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a touch screen in which at least one fingerprint & touch area and a plurality of touch areas are provided in a display area to simplify a circuit configuration of a touch IC, A fingerprint sensor integrated touch screen device and a driving method thereof are provided.

According to an aspect of the present invention, there is provided a fingerprint sensor integrated touchscreen device including a touch screen having at least one fingerprint & touch area and a plurality of touch areas, fingerprint & touch sensors, An analog integrator & and an analog-to-digital converter. Fingerprint & touch sensors are arranged in a first group of Tx lines arranged in parallel with each other in a first direction and a first group of Tx lines arranged in parallel with each other in a second direction intersecting the first direction in the fingerprint & Rx lines and intersections of the first group of Tx lines and the first group of Rx lines. The common sensing unit includes a plurality of common sensing units individually connected to the first group of Rx lines to sense a capacitance change of the fingerprint & touch sensors. The analog integrating amplifier amplifies the sensed values generated in the common sensing unit in a touch sensing mode for sensing a touch input and sequentially outputs sensed values generated in the common sensing unit in a fingerprint sensing mode for sensing a fingerprint input Amplify. The analog-to-digital converter is connected to the output terminal of the analog integrating &

According to another aspect of the present invention, there is provided a method of driving a fingerprint sensor integrated touch screen device having a touch screen including at least one fingerprint & touch area and a plurality of touch areas, A first group of Tx lines arranged in parallel to each other and a first group of Rx lines arranged in parallel with each other in a second direction intersecting with the first direction, A common sensing unit having a plurality of common sensing units individually connected to the first group of Rx lines for fingerprint & touch sensors formed at intersections of Rx lines of one group, Sensing the change in capacitance of the touch sensing unit in the touch sensing mode for sensing the touch input by using the analog integrating & Amplifying the sensed values generated in the common sensing unit in a fingerprint sensing mode for sensing the fingerprint input, integrating the values and sequentially sensing the output values of the analog integrator and the amplifier using a digital-to-analog converter .

The present invention does not include a sensing unit for fingerprint sensing and a sensing unit for touch sensing, which are targets of a fingerprint & touch area (FTAR) of a touch screen (TSP), but are unified through a common sensing unit (SSU). The present invention is characterized in that all the Rx lines (GP1 to Rx) connected to the fingerprint & touch area (FTAR) are individually sensed through the same common sensing unit (SSU) regardless of the sensing mode, Differently. In the touch sensing mode, the sensed values of the SSU are input to the analog integrator analog integrating & AIG and real-time integrated. According to the present invention, in the fingerprint sensing mode, values sensed in a common sensing unit (SSU) are sequentially input to an analog integrator & AIG and amplified.

The present invention amplifies the fingerprint sensing value to a predetermined level in consideration of the magnitude of the touch sensing value, thereby enabling the touch sensing value and the fingerprint sensing value to be digitally processed through one analog-to-digital converter.

Accordingly, in realizing the fingerprint sensor integrated touch screen device, the present invention has an advantage that the IC size and power consumption can be reduced by eliminating the latency in the touch IC 20 and simplifying the internal circuit configuration.

1 is a plan view schematically showing an arrangement of a driving electrode and a sensing electrode of a conventional capacitive sensing panel.
2 is a block diagram illustrating a display device to which a fingerprint sensor integrated touch screen device according to an embodiment of the present invention is applied.
3 is a view showing an example of a touch screen implemented by a mutual capacitance sensor.
4 is a view illustrating an example of a fingerprint sensor integrated touch screen according to an embodiment of the present invention.
5 is a waveform diagram of a sensor driving signal applied to a fingerprint sensor integrated touch screen in a touch sensing mode;
6 is a waveform diagram of a sensor driving signal applied to a fingerprint sensor integrated touch screen in a fingerprint sensing mode.
7 is a block diagram showing an internal configuration of a touch IC including a common sensing unit and a touch sensing unit.
8 is a circuit diagram showing an internal configuration of the touch IC in more detail.

The display device to which the fingerprint sensor integrated touch screen device of the present invention is applied includes a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP) A light emitting diode display device (OLED), and an electrophoresis display device (EPD). In the following embodiments, a display device is described as a liquid crystal display device as an example of a flat panel display device, but the display device of the present invention is not limited to a liquid crystal display device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

2 is a block diagram illustrating a display device to which a fingerprint sensor integrated touch screen device according to an embodiment of the present invention is applied. 3 shows an example of a touch screen implemented by a mutual capacitance sensor.

Referring to FIGS. 2 and 3, the fingerprint sensor integrated touch screen device of the present invention includes a touch screen (TSP) and a touch IC 20.

The fingerprint sensor integrated touch screen device of the present invention can be implemented as a capacitive touch screen (TSP) that senses a touch input through a plurality of capacitive sensors.

The capacitive touch screen includes a plurality of sensors. Each of the sensors includes a capacitance. Capacitance can be divided into Self Capacitance and Mutual Capacitance. The electrostatic capacitance can be formed along a single-layer conductor wiring formed in one direction, and mutual capacitance can be formed between two orthogonal conductor wiring.

The touch screen TSP implemented as the mutual capacitance sensor CM includes Tx lines (or Tx channels) arranged in parallel with each other in the first direction x, as shown in Fig. 3, along the second direction y Rx lines (or Rx channels) arranged side by side and intersecting Tx lines, and sensors CM formed at each intersection of Tx lines and Rx lines. Each mutual capacitance sensor CM includes a Tx electrode connected to the Tx line, an Rx electrode connected to the Rx line, and an insulating layer interposed therebetween. The Tx lines are driving signal wirings for applying a sensor driving pulse signal (hereinafter, sensor driving signal, VM) to each of the sensors CM to supply electric charges to the sensors. The Rx lines are sensor wirings connected to the sensors CM to supply the charge of the sensors to the touch IC 20. [ In the mutual capacitance sensing method, the sensor driving signal VM is applied to the Tx electrode of the mutual capacitance sensor CM through the Tx line to supply electric charge to the mutual capacitance sensor CM, Sensing the capacitance change through the Rx electrode and the Rx line of the capacitance sensor CM allows the touch input to be sensed.

The touch screen TSP may be bonded onto the upper polarizer plate of the display panel, or may be formed between the upper polarizer plate and the upper substrate of the display panel. In addition, the sensors CM of the touch screen TSP can be embedded in the pixel array of the display panel.

The touch screen TSP includes at least one fingerprint & touch area FTAR and a plurality of touch areas TAR. In the following embodiments, the fingerprint & touch area (FTAR) is described as one, but this is merely an example, and the present invention is not limited thereto. In the following embodiments, the fingerprint & touch area FTAR is described as being located at the center of the plurality of touch areas TAR. However, the position is not specified and any one of the touch areas TAR .

The fingerprint and touch area FTAR of the touch screen TSP includes a first group of Tx lines arranged in parallel with each other in a first direction x and a second group of Tx lines arranged in a second direction y Fingerprint & touch sensors are formed at the intersections of the first group of Rx lines and the first group of Tx lines and the first group of Rx lines. It is preferable that the fingerprint & touch sensor is finely implemented so that a plurality of fingerprint & touch sensors can be positioned between the ridge and the valley of the fingerprint.

Each of the touch areas TAR of the touch screen TSP includes a second group of Tx lines arranged in parallel with each other in the first direction x and sequentially driven in a bundle, And touch sensors formed at the intersections of the second group of Tx lines and the second group of Rx lines. The touch sensors may be implemented at the same size (or resolution) as the fingerprint & touch sensors, or at a larger size (or resolution) than the fingerprint & touch sensors. In the following description of the embodiments, it is shown that the touch sensor is formed to have the same size as the fingerprint & touch sensor, but it should be noted that the technical idea of the present invention is not limited thereto.

The touch IC 20 unifies the sensing unit for the fingerprint sensing and the sensing unit for the touch sensing, which are targets of the fingerprint & touch area FTAR of the touch screen TSP. Further, the touch IC 20 similarly adjusts the signal level of the fingerprint sensing value and that of the touch sensing value so that the touch sensing value and the fingerprint sensing value can be digitally processed in the analog-to-digital converter. Thus, the circuit configuration of the touch IC can be simplified, and the size and power consumption of the touch IC are reduced. This will be described in detail with reference to FIG. 7 and FIG.

The touch report output from the touch IC 20 may be transmitted to the host system 18 including the touch coordinate information TDATA and the fingerprint detection information FDATA.

The display device to which the fingerprint sensor integrated touch screen device of the present invention is applied may include a display panel (DIS), a display drive circuit (12, 14, 16), and a host system (18).

The display panel DIS includes a liquid crystal layer formed between two substrates. The pixel array of the display panel DIS includes pixels formed in the pixel region defined by the data lines (D1 to Dm, m is a positive integer) and the gate lines (G1 to Gn, n is a positive integer) . Each of the pixels is connected to TFTs (Thin Film Transistors) formed at intersections of the data lines D1 to Dm and the gate lines G1 to Gn, a pixel electrode for charging a data voltage, A storage capacitor (Cst) for maintaining a voltage, and the like.

A black matrix, a color filter, and the like may be formed on the upper substrate of the display panel DIS. The lower substrate of the display panel DIS may be implemented with a COT (Color Filter On TFT) structure. In this case, the black matrix and the color filter can be formed on the lower substrate of the display panel DIS. The common electrode to which the common voltage is supplied may be formed on the upper substrate or the lower substrate of the display panel DIS. On the upper substrate and the lower substrate of the display panel DIS, a polarizing plate is attached, and an alignment film for forming a pre-tilt angle of the liquid crystal on the inner surface in contact with the liquid crystal is formed. A column spacer for maintaining a cell gap of the liquid crystal cell is formed between the upper substrate and the lower substrate of the display panel DIS.

A backlight unit may be disposed below the rear surface of the display panel DIS. The backlight unit is implemented as an edge type or direct type backlight unit, and irradiates the display panel (DIS) with light. The display panel DIS may be implemented in any known liquid crystal mode such as TN (Twisted Nematic) mode, VA (Vertical Alignment) mode, IPS (In Plane Switching) mode and FFS (Fringe Field Switching) mode.

The display driving circuit includes a data driving circuit 12, a scan driving circuit 14, and a timing controller 16, and writes video data of the input image to pixels of the display panel DIS. The data driving circuit 12 converts the digital video data RGB input from the timing controller 16 into an analog positive / negative gamma compensation voltage to output a data voltage. The data voltage output from the data driving circuit 12 is supplied to the data lines D1 to Dm. The scan driving circuit 14 sequentially supplies a gate pulse (or a scan pulse) synchronized with the data voltage to the gate lines G1 to Gn to select a pixel line of the display panel DIS to which the data voltage is written.

The timing controller 16 inputs timing signals such as a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE and a main clock MCLK input from the host system 18 And synchronizes the operation timings of the data driving circuit 12 and the scan driving circuit 14 with each other. The scan timing control signal includes a gate start pulse (GSP), a gate shift clock, a gate output enable signal (GOE), and the like. The data timing control signal includes a source sampling clock (SSC), a polarity control signal (Polarity), a source output enable signal (SOE), and the like.

The host system 18 may be implemented in any one of a television system, a set-top box, a navigation system, a DVD player, a Blu-ray player, a personal computer (PC), a home theater system, and a phone system. The host system 18 includes a system on chip (SoC) with a built-in scaler to convert the digital video data RGB of the input image into a format suitable for display on the display panel DIS. The host system 18 transmits timing signals (Vsync, Hsync, DE, MCLK) to the timing controller 16 together with the digital video data. The host system 18 also executes an application program associated with the touch report input from the touch IC 20. [

FIG. 4 illustrates an example of a fingerprint sensor integrated touch screen according to an embodiment of the present invention. FIG. 5 is a waveform diagram of a sensor driving signal applied to the fingerprint sensor integrated touch screen in the touch sensing mode, and FIG. 6 is a waveform diagram of a sensor driving signal applied to the fingerprint sensor integrated touch screen in the fingerprint sensing mode.

Referring to FIG. 4, a fingerprint & touch area FTAR of a touch screen TSP includes a first group of Tx lines GP1-Tx arranged in parallel with each other in a first direction x, a first group of Rx lines GP1-Rx arranged in parallel with each other in a second direction y intersecting the first group Rx lines x and a first group of Rx lines GP1- Fingerprint and touch sensors FTa formed at the intersections of the plurality of fingerprint sensors GP1-Rx.

A second group of Tx lines GP2-Tx arranged in parallel in the first direction x and arranged in parallel with each other and driven in tandem in a plurality of touch regions TAR of the touch screen TSP, y and the intersection points of the second group of Rx lines GP2-Rx and the second group of Tx lines GP2-Tx and GP2-Rx, The touch sensors Ta are formed.

The touch IC 20 activates the touch sensing mode in accordance with the touch sensing enable signal (TEN in FIG. 8) input to the host system 18, and according to the fingerprint sensing enable signal (FEN in FIG. 8) Activate the mode.

In the touch sensing mode TMODE, the touch IC 20 sequentially drives a plurality of the second group of Tx lines GP2-Tx and sequentially drives the second group of Rx lines GP2 -Rx) are grouped and sensed. In the touch sensing mode TMODE, the touch IC 20 ties and simultaneously drives the first group of Tx lines GP1-Tx as shown in FIG. 5, and synchronously drives the first group of Rx lines GP1 -Rx) are individually sensed. In the touch sensing mode TMODE, the touch IC 20 senses the amount of charge change of the sensor input through the Rx lines GP1-Rx and GP2-Rx of the first and second groups, Judge whether or not to touch and its position.

In the fingerprint sensing mode (FMODE), the touch IC 20 successively drives the first group of Tx lines GP1-Tx individually one line at a time, and synchronously drives the first group of Rx lines (GP1-Rx) are individually sensed. In the fingerprint sensing mode (FMODE), the touch IC 20 senses the charge variation of the sensor input through the first group of Rx lines (GP1-Rx) to determine fingerprint input.

7 is a block diagram showing an internal configuration of a touch IC including a common sensing unit and a touch sensing unit. 8 is a circuit diagram showing the internal structure of the touch IC in more detail.

7 and 8, the touch IC 20 includes a plurality of touch sensing units TSU, a common sensing unit SSU, a switching block SB, an analog integrator analog integrating & And an analog-to-digital converter (ADC).

The common sensing unit SSU includes a plurality of common sensing units SSUa individually connected to the first group of Rx lines GP1 to Rx to sense the capacitance change of the fingerprint & touch sensors. Each of the common sensing units SSUa includes an operational amplifier OP and a first sensing capacitor Cfb1. The inverting input terminal (-) of the operational amplifier OP is connected to one of the first group of Rx lines GP1-Rx and the non-inverting input terminal (+) of the operational amplifier OP is connected to the reference voltage Vref And the output terminal of the operational amplifier OP may be connected to the inverting input terminal (-) of the operational amplifier OP via the first sensing capacitor Cfb1. The first sensing capacitor Cfb1 accumulates the sensing signals of the fingerprint & touch sensors input through the inverting input terminal (-).

Here, the common sensing units SSUa of the common sensing unit SSU operating in the touch sensing mode and the common sensing units SSUa of the common sensing unit SSU operating in the fingerprint sensing mode are the same. That is, the common sensing unit (SSU) of the present invention senses the capacitance change of the fingerprint & touch sensors using the same common sensing units SSUa irrespective of the touch sensing mode and the fingerprint sensing mode.

The analog integrator analog integrator & AIG operates as an analog integrator in a touch sensing mode for sensing the touch input, and integrates the sensed values generated in the common sensing unit (SSU) in real time. The analog integrator & amplifier (AIG) operates as an amplifier in fingerprint sensing mode for sensing fingerprint input and sequentially amplifies sensed values generated in a common sensing unit (SSU).

In particular, an analog-to-digital converter (ADC) having the same fingerprint sensing value corresponding to each of the sensing values input from the common sensing units SSUa and SSUa and the touch sensing value obtained by integrating the sensing values input from the common sensing units SSUa (AIG) adjusts both the signal level of the fingerprint sensing value and the signal level of the touch sensing value to within the sensing range of the same analog-to-digital converter (ADC) so that they can all be digitally processed. To this end, the analog integrator & amp (AIG) amplifies the fingerprint sensing value to a predetermined level.

The analog integrator & AIG includes an op amp OP, first and second negative feedback resistors RT and RF, and a negative feedback switch SWs. The inverting input terminal (-) of the operational amplifier OP is commonly connected to a plurality of first resistors RL connected in parallel with each other and also connected to a second resistor RLF. The non-inverting input terminal (+) of the op amp (OP) is connected to the base voltage source. The first and second sub feedback resistors RT and RF are selectively connected between the inverting input terminal (-) and the output terminal of the operational amplifier OP through a negative feedback switch SWs.

The sub feedback switch SWs is switched to Tst according to the touch sensing enable signal TEN in the touch sensing mode so that the first sub feedback resistor RT is connected between the inverting input terminal (-) of the op- . At this time, the inverting input terminal (-) of the operational amplifier OP simultaneously receives m sensing values generated by the common sensing unit (SSU) through m first resistors RL. In this touch sensing mode, the gain value of the analog integrator & amp (AIG) is -m * (RT / RL).

The sub feedback switch SWs is switched to Tsf according to the fingerprint sensing enable signal FEN in the fingerprint sensing mode so that the second sub feedback resistor RF is connected between the inverting input terminal (-) of the op- . At this time, the inverting input terminal (-) of the operational amplifier OP sequentially receives the m sensing values generated by the common sensing unit SSU through one second resistor RLF. In this fingerprint sensing mode, the gain value of the analog integrator & AIG is - (RF / RLF). Since the desired amplification ratio is determined according to the ratio of the second resistor RLF and the second negative feedback resistor RF, it is necessary to appropriately design the values of these resistors RLF and RF.

The switching block SB is connected between the common sensing unit SSU and the analog integrating amplifier AIG and includes a sample and hold unit SH for sampling and holding the sensing values generated in the common sensing unit SSU, And includes a plurality of switches SW.

In the touch sensing mode, the switches SW are simultaneously switched to Tt according to the touch sensing enable signal TEN so that the output terminals To of the sample and hold section SH are connected to the first resistor < RTI ID = 0.0 >Lt; RTI ID = 0.0 > RL.

In the fingerprint sensing mode, the switches SW are sequentially switched from Tf1 to Tfm according to the fingerprint sensing enable signal FEN to sequentially output the output terminals To of the sample and hold section SH to the analog integrator & 2 resistors (RLF).

Each of the touch sensing units TSU includes a touch sensing unit for simultaneously sensing a plurality of Rx lines GP2-Rx of the second group and sensing the capacitance change of the touch sensors. The touch sensing unit includes an operational amplifier OP and a second sensing capacitor Cfb2. The inverting input terminal (-) of the operational amplifier OP is commonly connected to the second group of Rx lines GP2-Rx and the non-inverting input terminal (+) of the operational amplifier OP is connected to the reference voltage Vref input And the output terminal of the operational amplifier OP may be connected to the inverting input terminal (-) of the operational amplifier OP via the second sensing capacitor Cfb2. The second sensing capacitor Cfb2 accumulates the sensing signals of the touch sensors input through the inverting input terminal (-).

Here, the capacitance of the second sensing capacitor Cfb2 is designed to be larger than that of the first sensing capacitor Cfb1. The capacity of the sensing capacitor is determined by the number of Rx lines to which the sensing unit is connected.

As described above, the present invention has an advantage in that the IC size and power consumption can be reduced by eliminating the latency in the touch IC 20 and simplifying the internal circuit structure in implementing the fingerprint sensor integrated touch screen device .

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

DIS: Display panel TSP: Touch screen
12: Data driving circuit 14: Scan driving circuit
16: timing controller 18: host system
20: Touch IC FTAR: Fingerprint & touch area
TAR: Touch area FTa: Fingerprint & touch sensor
Ta: touch sensor GP1-Tx: Tx lines of the first group
GP2-Tx: Tx lines of the second group GP1-Rx: Rx lines of the first group
GP2-Rx: Rx lines of the second group TSU: Touch sensing unit
SSU: common sensing unit SSUa: common sensing unit
SB: Switching block SH: Sample & hold part
SW: switch RL: first resistance
RLF: second resistor AIG: analog integrator & amplifier
OP: Op Amp RT: Part 1 Feedback Resistance
RF: Part 2 Feedback Resistor ADC: Analog-to-Digital Converter

Claims (14)

A fingerprint sensor integrated touch screen device having a touch screen including at least one fingerprint & touch area and a plurality of touch areas,
A first group of Tx lines arranged in parallel with each other in a first direction and a first group of Rx lines arranged in parallel with each other in a second direction intersecting the first direction in the fingerprint & Fingerprint & touch sensors formed at intersections of the first group of Tx lines and the first group of Rx lines;
A common sensing unit having a plurality of common sensing units individually connected to the first group of Rx lines to sense a capacitance change of the fingerprint & touch sensors;
An analog integrator for integrating sensed values generated in the common sensing unit in a touch sensing mode for sensing a touch input and sequentially amplifying sensed values generated in the common sensing unit in a fingerprint sensing mode for sensing a fingerprint input, amplifier; And
And an analog-to-digital converter connected to an output terminal of the analog integrating &
The method according to claim 1,
Wherein the common sensing units of the common sensing unit operating in the touch sensing mode and the common sensing units of the common sensing unit operating in the fingerprint sensing mode are the same.
3. The method of claim 2,
The analog integrating &
The fingerprint sensor integrated touchscreen device operating as an analog integrator in the touch sensing mode and operating as an analog amplifier in the fingerprint sensing mode.
The method of claim 3,
So that the touch sensing value obtained by integrating the sensing values input from the common sensing unit and the fingerprint sensing value corresponding to each of the sensing values input from the common sensing unit can be digitally processed through one analog- ,
And the analog integrating & amplifier amplifies the fingerprint sensing value to a predetermined level.
The method according to claim 1,
Further comprising a switching block connected between the common sensing unit and the analog integrating &
The switching block includes:
A sample and hold unit for sampling and holding the sensing values generated in the common sensing unit; And
Wherein in the touch sensing mode, the sample-and-hold unit is switched to be connected to a plurality of first resistors connected in parallel with each other in the analog integrating & amplifier, and in the fingerprint sensing mode, 2 fingerprint sensor integrated touch screen device having a plurality of switches that are switched to be connected to a resistor.
6. The method of claim 5,
The analog integrating &
An op amp having an inverting input terminal commonly connected to the first resistors and the second resistor, a non-inverting input terminal connected to the base voltage source, and an output terminal connected to the analog-to-digital converter; And
In the touch sensing mode, the inverting input terminal of the operational amplifier is switched to be connected to the output terminal of the operational amplifier through the first negative feedback resistor, and the inverting input terminal of the operational amplifier is switched to the second negative feedback resistance And a negative feedback switch which is switched to be connected to the output terminal of the operational amplifier through the auxiliary switch.
The method according to claim 1,
Wherein the first group of Tx lines are sequentially driven one line at a time in the fingerprint sensing mode and simultaneously driven in the touch sensing mode.
The method according to claim 1,
A second group of Tx lines arranged in parallel with each other in the first direction and sequentially driven in a bundled manner and a second group of Rx lines arranged in parallel with each other in the second direction, Touch sensors formed at intersections of the second group of Tx lines and the second group of Rx lines; And
And a touch sensing unit for simultaneously sensing a plurality of Rx lines of the second group and sensing the capacities of the Rx lines of the second group at the same time.
A method of driving a fingerprint sensor integrated touch screen device having a touch screen including at least one fingerprint & touch area and a plurality of touch areas,
A first group of Tx lines arranged in parallel with each other in a first direction and a first group of Rx lines arranged in parallel with each other in a second direction intersecting the first direction in the fingerprint & Fingerprint & touch sensors formed at intersections of the first group of Tx lines and the first group of Rx lines,
Sensing a capacitance change of the fingerprint & touch sensors using a common sensing unit having a plurality of common sensing units individually connected to the first group of Rx lines;
The integrated value is calculated by integrating the sensing values generated in the common sensing unit in the touch sensing mode for sensing the touch input by using the analog integrating amplifier and the sensing value generated in the common sensing unit in the fingerprint sensing mode for sensing the fingerprint input, Sequentially amplifying the signals; And
And converting the output value of the analog integrator & amplifier to a digital value using an analog-to-digital converter.
10. The method of claim 9,
Wherein the common sensing units of the common sensing unit operating in the touch sensing mode and the common sensing units of the common sensing unit operating in the fingerprint sensing mode are the same.
11. The method of claim 10,
And operating the analog integrating & operating in the touch sensing mode with an analog integrator, and in the fingerprint sensing mode, operating the analog integrating &
12. The method of claim 11,
The step of sequentially amplifying the sensing values generated in the common sensing unit includes:
So that the touch sensing value obtained by integrating the sensing values input from the common sensing unit and the fingerprint sensing value corresponding to each of the sensing values input from the common sensing unit can be digitally processed through one analog- And a step of amplifying the fingerprint sensing value to a predetermined level.
10. The method of claim 9,
Wherein the first group of Tx lines are sequentially driven one line at a time in the fingerprint sensing mode and simultaneously driven in the touch sensing mode.
10. The method of claim 9,
A second group of Tx lines arranged in parallel with each other in the first direction and sequentially driven in a bundled manner and a second group of Rx lines arranged in parallel with each other in the second direction, And touch sensors formed at intersections of the second group of Tx lines and the second group of Rx lines,
Sensing a capacitance change of the touch sensors using at least one or more touch sensing units having a touch sensing unit for simultaneously sensing a plurality of Rx lines of the second group and sensing the same, Way.

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