WO2020215537A1 - 触摸检测电路、触控显示装置以及触摸检测方法 - Google Patents

触摸检测电路、触控显示装置以及触摸检测方法 Download PDF

Info

Publication number
WO2020215537A1
WO2020215537A1 PCT/CN2019/101023 CN2019101023W WO2020215537A1 WO 2020215537 A1 WO2020215537 A1 WO 2020215537A1 CN 2019101023 W CN2019101023 W CN 2019101023W WO 2020215537 A1 WO2020215537 A1 WO 2020215537A1
Authority
WO
WIPO (PCT)
Prior art keywords
switch
capacitor
compensation capacitor
touch detection
voltage
Prior art date
Application number
PCT/CN2019/101023
Other languages
English (en)
French (fr)
Inventor
刘成
Original Assignee
北京集创北方科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 北京集创北方科技股份有限公司 filed Critical 北京集创北方科技股份有限公司
Priority to KR1020207036587A priority Critical patent/KR102491774B1/ko
Priority to JP2020552722A priority patent/JP7319291B2/ja
Publication of WO2020215537A1 publication Critical patent/WO2020215537A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G06F3/0418—Control or interface arrangements specially adapted for digitisers for error correction or compensation, e.g. based on parallax, calibration or alignment
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0412—Digitisers structurally integrated in a display
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means

Definitions

  • the present invention relates to the field of touch technology, in particular to a touch detection circuit, a touch display device and a touch detection method.
  • Existing capacitive touch device detection methods have two basic schemes based on self-capacitance detection and mutual capacitance detection. Both basic schemes are based on detecting the tiny capacitance caused by a conductor (such as a human finger) approaching the capacitive touch device. Change to realize the recognition operation. In general, the capacitance change caused by the conductor approaching the device is much smaller than the measured capacitance of the device. These measured capacitances include the capacitance of the screen itself and the parasitic capacitance of the screen. Due to the existence of the measured capacitance, the effective detection range of the detection circuit is limited, thereby limiting the improvement of the detection sensitivity for small capacitance changes.
  • the prior art often adopts a method of adding a compensation capacitor to the original touch detection circuit.
  • the power of the measured capacitor is reduced by a predetermined amount, so that the measured capacitance is Compared with the capacitance change when there is no compensation capacitor, the capacitance change of, thereby improving the sensitivity of the detection circuit.
  • MIM Metal-Insulator-Metal, metal-insulator-metal
  • MOM Metal-Oxide-Metal, metal-oxide-metal
  • the present invention provides a touch detection circuit, a touch display device, and a touch detection method, which can reduce the chip area and reduce the chip cost.
  • the touch detection circuit is characterized by comprising: an operational amplifier, including an inverting input terminal for receiving a capacitance sensing signal, a non-inverting input terminal for receiving a common mode voltage, and an output terminal for providing a detection signal; a compensation capacitor , To compensate the capacitance sensing signal to increase the signal sensitivity; and a plurality of switches are connected to the compensation capacitor to connect or disconnect the compensation capacitor and the inverting input terminal, the first bias terminal, and the second The electrical connection of the second bias terminal and the third bias terminal, wherein the plurality of switches include a ninth switch connected between the inverting input terminal and the first terminal of the compensation capacitor, and the plurality of switches are used for When the ninth switch is turned off, charging/discharging the upper and lower plates of the compensation capacitor is realized, and the pressure difference between the upper and lower plates of the compensation capacitor is balanced.
  • the compensation capacitor includes a metal oxide semiconductor capacitor.
  • the touch detection circuit further includes: a basic capacitor, the first terminal of the basic capacitor is connected to the inverting input terminal of the operational amplifier through a second switch, and the second terminal is grounded; a voltage source, the voltage source via The first switch is connected to the first end of the basic capacitor for charging the basic capacitor; the third switch is connected in series with the inverting input terminal of the operational amplifier and the output of the operational amplifier A first capacitor, the first capacitor is connected in parallel with the third switch.
  • the plurality of switches further include: a fourth switch connected between the first terminal of the compensation capacitor and the first bias terminal; a fifth switch, the fifth switch Connected between the first terminal of the compensation capacitor and the third bias terminal; a sixth switch, the sixth switch is connected between the second terminal of the compensation capacitor and the first bias terminal A seventh switch, the seventh switch is connected between the second end of the compensation capacitor and the third bias end; the eighth switch, the eighth switch is connected to the second end of the compensation capacitor And the second bias end.
  • the first bias terminal is a positive voltage source bias terminal
  • the second bias terminal is a negative voltage source bias terminal
  • the third bias terminal is an analog ground bias terminal.
  • the fourth switch and the seventh switch are closed, and the compensation capacitor is charged to the first voltage.
  • the sixth switch and the ninth switch are closed, the charge on the compensation capacitor is transferred to the basic capacitor, and the fifth switch and the seventh switch are closed in the first time period before the falling edge of the excitation signal is triggered, Discharge the upper and lower plates of the compensation capacitor, and close the eighth switch and the ninth switch in the first time period after the falling edge of the excitation signal is triggered to charge the compensation capacitor to the second voltage, and at the same time The charge on the base capacitor is transferred to the compensation capacitor.
  • the output voltage of the bias terminal of the positive voltage source and the output voltage of the bias terminal of the negative voltage source have the same voltage magnitude and opposite voltage polarity.
  • the absolute values of the first voltage and the second voltage are equal.
  • the output voltage of the voltage source can be switched between a positive voltage and a negative voltage.
  • a touch display device provided according to the present invention is characterized by comprising: a display panel and the touch detection circuit according to any one of claims 1 to 9, and the touch detection circuit is used to provide a detection signal.
  • the display panel includes: a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a Mirco-LED display panel, and a Mini-LED Display panel, field emission display panel, plasma display panel, electrophoretic display panel or electrowetting display panel.
  • the touch detection method provided according to the present invention is characterized in that it comprises: in the first time period before the rising edge or the falling edge of the excitation signal is triggered, the basic capacitor is charged by the voltage source according to the excitation signal; In the first time period after the rising or falling edge of the trigger, the basic capacitance is compensated by the compensation capacitor, wherein when the compensation capacitor compensates the basic capacitance, a plurality of bias terminals are used according to the excitation signal Charge/discharge the upper and lower plates of the compensation capacitor.
  • the multiple bias terminals include: a positive voltage source bias terminal, a negative voltage source bias terminal, and an analog ground bias terminal.
  • the compensation capacitor includes a metal oxide semiconductor capacitor.
  • the output voltage of the voltage source when the excitation signal is at a high level, the output voltage of the voltage source is a positive voltage, and when the excitation signal is at a low level, the output voltage of the voltage source is a negative voltage.
  • the touch detection method further includes: when the compensation capacitor compensates the basic capacitance, an operational amplifier detects and outputs the amount of change of the basic capacitance.
  • the method for compensating the basic capacitance includes: charging the compensation capacitor to a first voltage in the first time period before the rising edge of the excitation signal is triggered; after the rising edge of the excitation signal is triggered In the first period of time, the charge on the compensation capacitor is transferred to the basic capacitor; in the first period of time before the falling edge of the excitation signal is triggered, the upper and lower plates of the compensation capacitor are discharged; In the first time period after the falling edge of the excitation signal is triggered, the compensation capacitor is charged to a second voltage, and at the same time the charge on the basic capacitor is transferred to the compensation capacitor.
  • the charge is a positive charge.
  • the absolute values of the first voltage and the second voltage are equal.
  • the present invention provides a touch detection circuit, a touch display device and a touch detection method.
  • the basic capacitance in the touch detection circuit is compensated by sampling the metal oxide semiconductor capacitance as the basic capacitance.
  • the chip area is reduced, and since the capacitance per unit area of the metal oxide semiconductor capacitor is twice that of the MIM capacitor, the area of the compensation capacitor is also reduced to a certain extent, which greatly reduces the chip cost.
  • the two ends of the NCAP capacitor are connected to multiple bias sources by setting the corresponding switch circuit, and the upper and lower plates of the NCAP capacitor are charged/discharged through the multiple bias sources, effectively eliminating the pressure difference between the upper and lower plates of the NCAP.
  • the plates of the present invention during the remaining capacitance C b basis of positive / negative charging voltage converter, the upper plate and the lower electrode of the compensation capacitor C c connected to analog ground simultaneously, thus freeing compensation capacitor C c of the upper plate and the lower The charge further improves the compensation effect of the compensation capacitor C c on the basic capacitor C b .
  • Fig. 1 shows a schematic structural diagram of a touch detection circuit according to the prior art
  • FIG. 2 shows a schematic structural diagram of a touch detection circuit provided by an embodiment of the present invention
  • FIG. 3 shows a control timing diagram of a touch detection circuit provided by an embodiment of the present invention
  • FIG. 4 shows a flowchart of a touch detection method provided by an embodiment of the present invention
  • Fig. 5 shows a flowchart of a basic capacitance compensation method provided by an embodiment of the present invention.
  • Fig. 1 shows a schematic structural diagram of a touch detection circuit according to the prior art.
  • the touch detection circuit includes: a basic capacitor C b , a first capacitor C f , a compensation capacitor C c , an operational amplifier AMP, a first switch S1, a second switch S2, a third switch S3, and a fourth switch S4 And the fifth switch S5, where the basic capacitance C b corresponds to the capacitance to ground of each pixel.
  • the first terminal of the basic capacitor C b is connected to the first terminal of the first switch S1 and the first terminal of the second switch S2 at the same time, the second terminal of the basic capacitor C b is grounded; the second terminal of the first switch S1 is connected to the voltage Source; the second terminal of the second switch S2 is connected to the inverting input terminal of the operational amplifier AMP; the third switch S3 is connected between the output terminal and the inverting input terminal of the operational amplifier AMP; the first capacitor C f and the third switch S3 is connected in parallel; the non-inverting input terminal of the operational amplifier AMP receives the common mode voltage VCM, and the output terminal of the operational amplifier AMP is used to output the detection signal Vo; the first end of the compensation capacitor C c is connected to the inverting input terminal of the operational amplifier AMP, and the compensation capacitor The second end of C c is respectively connected to the first end of the fourth switch S4 and the first end of the fifth switch S5, and the second end of the fourth switch S4 and the second end of the fifth switch S
  • the amount of change in the basic capacitance C b caused by touch is equivalent to the touch capacitance ⁇ C connected in parallel with the basic capacitance C b .
  • the voltage source, the first compensation voltage source, and the second compensation voltage source include any one selected from a positive voltage source VDD and a negative voltage source VSS.
  • the touch detection circuit shown in FIG. 1 comprises two periods [Psi] 1 and [psi] 2, mainly on the basis of capacitance C b [Psi] 1 during charging, on the basis of the main capacitance C b to perform compensation during ⁇ 2.
  • the symbols ⁇ 1 and ⁇ 2 in the circuit diagram of Figure 1 indicate: during ⁇ 1, the switch corresponding to ⁇ 1 is closed, and the switch corresponding to ⁇ 2 is off; and during ⁇ 2, the switch corresponding to ⁇ 1 is off, and the switch corresponding to ⁇ 2 is open. closure.
  • the first switch S1, the third switch S3, and the fourth switch S4 are all closed, and the second switch S2 and the fifth switch S5 are all open.
  • the base capacitor C b starts to be charged through the first switch S1
  • the compensation capacitor C c starts to be charged through the fourth switch S4.
  • the voltage source is, for example, a positive voltage source VDD
  • the first compensation voltage source is, for example, a negative voltage source VSS.
  • the operational amplifier AMP is connected to a unity gain buffer. From the relevant characteristics of the unity gain buffer, it can be known that the output terminal voltage of the operational amplifier AMP is equal to the non-inverting input terminal voltage, which corresponds to the common mode voltage VCM.
  • the first switch S1, the third switch S3, and the fourth switch S4 are all turned off, and the second switch S2 and the fifth switch S5 are closed, so that the operational amplifier AMP works in the linear region.
  • the non-inverting input terminal and the inverting input terminal of AMP are regarded as equipotential. This characteristic is called false short circuit, or virtual short for short. Due to this characteristic of the operational amplifier AMP, at this time, both the non-inverting input terminal and the inverting input terminal voltage of the operational amplifier AMP correspond to the common-mode voltage VCM.
  • the output terminal of the operational amplifier AMP is connected to an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used to obtain the touch capacitance ⁇ C according to the variation of the detection signal Vo.
  • the fourth switch S4, the fifth switch S5, and the compensation capacitor C c are added .
  • the second compensation voltage source is, for example, VDD
  • the fifth switch S5 is closed, so that the voltage across the compensation capacitor C c corresponds to VDD-VSS, charge transfer occurs between the basic capacitor C b and the compensation capacitor C c , the power of the basic capacitor C b is reduced, so that the capacitance change of the basic capacitor C b (ie touch capacitance ⁇ C) is relative to the uncompensated capacitor C
  • the sensitivity of the detection circuit is improved.
  • FIG. 2 shows a schematic structural diagram of a touch detection circuit provided by an embodiment of the present invention.
  • the touch detection circuit includes: a basic capacitor C b , a first capacitor C f , a compensation capacitor C c , a plurality of switches, an operational amplifier AMP, a first switch S1, a second switch S2, and The third switch S3.
  • the operational amplifier AMP includes an inverting input terminal for receiving a capacitance sensing signal, a non-inverting input terminal for receiving a common mode voltage VCM, and an output terminal Vo for providing a detection signal.
  • the output terminal of the operational amplifier AMP is connected to an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used to obtain the touch capacitance ⁇ C according to the variation of the detection signal Vo.
  • the third switch S3 is connected between the output terminal and the inverting input terminal of the operational amplifier AMP; the first capacitor C f is connected in parallel with the third switch S3.
  • the first end of the compensation capacitor C c is connected to the first end of the basic capacitor C b via the second switch S2, and the compensation capacitor C c is used to compensate the basic capacitor C b .
  • the compensation capacitor C c adopts an NCAP capacitor (that is, an N-well capacitor or a metal oxide semiconductor capacitor), and the capacitance per unit area of the N-well capacitor is twice that of a traditional metal insulation layer metal capacitor, which includes There are: a basic doped area doped according to the basic doping type; at least one doped connection area, which is preferably adjacent to the basic doped area and doped according to the basic doping type, and its maximum dopant concentration is higher than the basic doped area The maximum dopant concentration is high; and the electrode area arranged at a certain distance from the basic doped area, which is also called the gate area according to the structure of the MOS transistor (metal oxide semiconductor), and is arranged in the electrode area and the basic doped area.
  • the dielectric between the doped regions that is, an N-well capacitor or a metal oxide semiconductor capacitor
  • the compensation capacitor C c may also include other capacitors with higher capacitance per unit area.
  • a plurality of switches are connected to the compensation capacitor C c , and the plurality of switches are used to connect or disconnect the compensation capacitor C c and the inverting input terminal, the first bias terminal, the second bias terminal and the third bias terminal of the operational amplifier AMP. Electrical connection to the bias end.
  • the plurality of switches includes a ninth switch S9 connected between the first terminal of the compensation capacitor C c and the inverting input terminal of the operational amplifier AMP.
  • the ninth switch S9 can be used as a steering switch to connect the compensation capacitor C c and the inverting input terminal of the operational amplifier AMP when the ninth switch S9 is turned on, and realize the bidirectional (charge) between the compensation capacitor C c and the basic capacitor C b . Transfer direction) compensation; and the multiple switches are used to charge/discharge the upper and lower plates of the compensation capacitor C c when the ninth switch S9 is turned off, and balance the pressure difference between the upper and lower plates of the compensation capacitor C c .
  • the plurality of switches further include a fourth switch S4, a fifth switch S5, a sixth switch S6, a seventh switch S7, and an eighth switch S8.
  • the plurality of switches are used to turn on the first switch of the compensation capacitor C c .
  • One end and the second end are respectively connected to a plurality of bias terminals to balance the pressure difference between the upper and lower plates of the compensation capacitor C c , and further eliminate the difference in capacitance of the compensation capacitor C c when a metal oxide semiconductor capacitor is used as the compensation capacitor.
  • the conduction of the plurality of switches is controlled by the excitation signal.
  • the fourth switch S4 is connected between the first end of the compensation capacitor C c and the first bias end (positive voltage source) VDP;
  • the fifth switch S5 is connected between the first end of the compensation capacitor C c and the third bias Terminal (analog ground) VSS;
  • the sixth switch S6 is connected between the second terminal of the compensation capacitor C c and the first bias terminal (positive voltage source) VDP;
  • the seventh switch S7 is connected to the second terminal of the compensation capacitor C c Between the second terminal and the third bias terminal (analog ground) VSS;
  • the eighth switch S8 is connected between the second terminal of the compensation capacitor C c and the second bias terminal (negative voltage source) VDN.
  • the compensation capacitor C c , multiple switches, and multiple bias terminals can form a compensation module 100, and the compensation module 100 is mainly used to realize compensation for external signals. It can be understood that the compensation module 100 can also be applied to other circuits.
  • the basic capacitance C b corresponds to the capacitance to ground of each pixel.
  • the first terminal is connected to the inverting input terminal of the operational amplifier AMP through the second switch S2, and the second terminal is grounded.
  • the voltage source is connected to the second end of the basic capacitor Cb through the first switch S1, and the voltage source includes any one selected from a positive voltage source VDP and a negative voltage source VDN.
  • the voltage source output voltage can be switched between positive voltage and negative voltage according to the excitation signal.
  • the voltage source when the excitation signal is high, the voltage source outputs a positive voltage VDP.
  • the voltage The source When the excitation signal is low, the voltage The source outputs a negative voltage VDN.
  • the amount of change in the basic capacitance C b caused by touch is equivalent to the touch capacitance ⁇ C connected in parallel with the basic capacitance C b , corresponding to the capacitance sensing signal.
  • the absolute voltages of the positive voltage source VDP and the negative voltage source VDN are equal, that is, the voltages of the positive voltage source VDP and the negative voltage source VDN are equal, and the voltage polarity is opposite.
  • FIG. 3 shows a control timing diagram of the touch detection circuit provided by an embodiment of the present invention.
  • the operating timing of the touch detection circuit is divided into a first time period t1, a second time period t2, a third time period t3, and a fourth time period t4.
  • the time periods t1 and t3 correspond to the charging time period of the basic capacitor
  • the time periods t2 and t4 correspond to the time period for performing charge compensation on the basic capacitor.
  • the first time period before the rising edge of the excitation signal is used to represent the first time period t1; the first time period after the rising edge of the excitation signal is triggered to represent the second time period t2; The first time period before the falling edge of the excitation signal is triggered represents the third time period t3; and the first time period after the falling edge of the excitation signal is triggered represents the fourth time period t4. Further, at the transition time point of the first time period t1 and the second time period t2, the excitation signal is triggered at the rising edge, and at the transition time point of the third time period t3 and the fourth time period t4, the excitation signal is triggered at the falling edge.
  • the high-level signal corresponds to the closed state of the corresponding switch
  • the low-level signal corresponds to the open state of the corresponding switch.
  • the excitation signal is at a low level, and the voltage source is switched to the negative voltage source VDN.
  • the first switch S1 and the third switch S3 are closed, the second switch S2 is opened, and the basic capacitor C b starts to be negatively charged via the first switch S1.
  • the first voltage across the two ends corresponds to VDN.
  • the fourth switch S4 and the seventh switch S7 are closed, the fifth switch S5, the sixth switch S6, and the eighth switch S8 are opened.
  • the upper plate of the compensation capacitor C c is connected to the positive voltage source VDP via the fourth switch S4, and the lower The plate is connected to the analog ground VSS via the seventh switch S7.
  • the positive voltage source VDP starts to charge the upper plate of the compensation capacitor C c .
  • the voltage at both ends of the compensation capacitor C c corresponds to VDP, and at this time the charge on the compensation capacitor C c Is C c *(VDP-VSS).
  • the excitation signal is at a high level, and the voltage source is switched to the positive voltage source VDP.
  • the second switch S2 is closed, the first switch S1 and the third switch S3 are disconnected, the basic capacitor C b is no longer charged, and the first end of the basic capacitor C b is connected to the node VIN through the second switch S2.
  • the sixth switch S6 and the ninth switch S9 are closed, and the fourth switch S4, the fifth switch S5, the seventh switch S7, and the eighth switch S8 are opened.
  • the upper plate of the compensation capacitor C c is connected to the node VIN via the ninth switch S9 (the voltage of the node VIN is also VDP), and the lower plate of the compensation capacitor C c is connected to the positive voltage source VDP via the sixth switch S6.
  • the excitation signal remains at a high level and the voltage source is a positive voltage source VDP.
  • the first switch S1 and the third switch S3 are closed, the second switch S2 is opened, and the basic capacitor C b starts to be positively charged via the first switch S1, and after the charging is completed, the second voltage across it corresponds to VDP.
  • the fifth switch S5 and the seventh switch S7 are closed, the fourth switch S4, the sixth switch S6, the eighth switch S8 and the ninth switch S9 are opened, and the upper plate and the lower plate of the compensation capacitor C c pass through the
  • the fifth switch S5 and the seventh switch S7 are connected to the analog ground VSS, so the charge on the compensation capacitor C c is zero at this time, and the remaining charge on the upper and lower plates of the compensation capacitor C c can be released to further increase the compensation capacitor C c Compensation effect on basic capacitance C b .
  • the excitation signal is at a low level, and the voltage source is switched to the negative voltage source VDN.
  • the second switch S2 is closed, the first switch S1 and the third switch S3 are disconnected, the basic capacitor C b is no longer charged, and the first end of the basic capacitor C b is connected to the node VIN through the second switch S2.
  • the eighth switch S8 and the ninth switch S9 are closed, the fourth switch S4, the fifth switch S5, the sixth switch S6 and the seventh switch S7 are opened, and the upper plate of the compensation capacitor C c is connected to the node via the ninth switch S9 VIN (the voltage of the node VIN is also VSS at this time), and is connected to the first end of the basic capacitor C b through the second switch S2, and the bottom plate of the compensation capacitor C c is connected to the negative voltage source VDN through the eighth switch S8.
  • the absolute values of the first voltage VDN and the second voltage VDP are equal, and the voltage polarities are opposite.
  • the above-mentioned transferred charges are all positive charges.
  • the charge transfer between the basic capacitor C b and the compensation capacitor C c can reduce the power of the basic capacitor C b .
  • the capacitance of the basic capacitor C b The amount of change (that is, the touch capacitance ⁇ C) increases relative to the case of no compensation capacitance C c , which improves the sensitivity of the detection circuit.
  • the present invention is based capacitance C b during the positive / negative voltage charge conversion, compensation capacitor C c may be released from the lower plate and the charge electrode plate remains to further improve the compensation effect of the compensation capacitor C c capacitance C b of the base .
  • the NCAP capacitor (N-well capacitor or metal oxide semiconductor capacitor) is used as the compensation capacitor C c in the touch detection circuit, which effectively reduces the area of the chip and reduces the chip cost.
  • FIG. 4 shows a flowchart of a touch detection method provided by an embodiment of the present invention.
  • Fig. 5 shows a flowchart of a basic capacitance compensation method provided by an embodiment of the present invention.
  • the touch detection method mainly performs steps S100 to S300 on the touch detection circuit.
  • step S100 in the first time period before the rising edge or the falling edge of the excitation signal is triggered, the basic capacitor is charged by the voltage source according to the excitation signal.
  • the first switch S1 is closed, and the voltage source charges the basic capacitor C b through the first switch S1.
  • the second switch S2 is opened, the compensation capacitor C c does not perform charge compensation on the basic capacitor C b , and the third switch S3 is closed, and the operational amplifier AMP does not work.
  • the voltage polarity of the voltage source is determined by the excitation signal: for example, when the excitation signal is high, the voltage source charges the basic capacitor C b with a positive voltage VDP, and when the excitation signal is low, the voltage source charges the basic capacitor C b Perform negative voltage VDN charging.
  • step S200 in the first time period after the rising edge or the falling edge of the excitation signal is triggered, the basic capacitance is compensated by the compensation capacitor.
  • the multiple bias terminals include: a positive voltage source bias terminal, a negative voltage source bias terminal, and an analog ground bias terminal.
  • the compensation method of the compensation capacitor to the basic capacitor includes:
  • step S210 the compensation capacitor is charged to the first voltage in the first time period before the rising edge of the excitation signal is triggered.
  • the excitation signal is at a low level, and the voltage source charges the basic capacitor C b with a negative voltage VDN, and simultaneously closes the fourth switch S4 and the seventh switch S7: Charge the compensation capacitor C c with a positive voltage, so that the voltage difference between the two ends of the compensation capacitor C c is the first voltage VDP.
  • step S220 in the first time period after the rising edge of the excitation signal is triggered, the charge on the compensation capacitor is transferred to the basic capacitor.
  • the basic capacitor C b in the first time period after the rising edge of the excitation signal is triggered, the basic capacitor C b is fully charged, and the upper plate voltage is VDN. At this time, the rising edge of the excitation signal is triggered, and the first switch S1 and the third switch S3 are opened, and the second switch S2 is closed at the same time, and the basic capacitance C b is compensated by the compensation capacitor C c .
  • the compensation capacitor C c After the compensation capacitor C c is fully charged, its upper plate voltage is VDP. At this time, the fourth switch S4 and the seventh switch S7 are opened, and the sixth switch S6 and the ninth switch S9 are closed at the same time, so that the compensation capacitor C c The charge of the upper plate is transferred to the basic capacitor C b through the ninth switch S9 and the second switch S2 to complete the compensation of the basic capacitor C b .
  • step S230 in the first time period before the falling edge of the excitation signal is triggered, the upper and lower plates of the compensation capacitor are discharged.
  • the excitation signal is at a high level.
  • the second switch S2 is opened, the first switch S1 and the third switch S3 are closed, and the voltage source
  • the base capacitor C b is charged with a positive voltage through the first switch S1.
  • the sixth switch S6 and the ninth switch S9 are opened, and the fifth switch S5 and the seventh switch S7 are closed.
  • the upper and lower plates of the compensation capacitor C c are connected to the analog ground VSS, and the compensation capacitor C c is released. Residual charge on the upper and lower plates.
  • step S240 in the first time period after the falling edge of the excitation signal is triggered, the compensation capacitor is charged to the second voltage, and at the same time the charge on the basic capacitor is transferred to the compensation capacitor.
  • the basic capacitor C b in the first time period after the falling edge of the excitation signal is triggered, the basic capacitor C b is fully charged, and the upper plate voltage is VDP. At this time, the falling edge of the excitation signal is triggered, the first switch S1 and the third switch S3 are opened, and the second switch S2 is closed at the same time, and the basic capacitance C b is compensated by the compensation capacitor C c .
  • the second switch S2 when the second switch S2 is closed, the charge of the compensation capacitor C c is released and the upper plate voltage is zero.
  • the fifth switch S5 and the seventh switch S7 are opened, and the eighth switch S8 and the first switch S8 are closed.
  • the nine switch S9 charges the compensation capacitor C c with a negative voltage.
  • the charge on the upper plate of the compensation capacitor C c is the basic capacitor C b .
  • the charge on the upper plate of the capacitor C b is transferred from the second switch S2 and the ninth switch S9. Therefore, when the compensation capacitor C c is charged, the compensation capacitor C c is also At the same time, the basic capacitance C b is being compensated.
  • the voltage difference between the upper and lower electrode plates is the second voltage VDN.
  • the compensation capacitor C c compensates the basic capacitor C b
  • the charge transfers in two directions, because in this embodiment, the voltages of the positive voltage source VDP and the negative voltage source VDN are equal and opposite in polarity. Therefore, when the charge is transferred, the charge transferred from the basic capacitor C b to the compensation capacitor C c is equal to the charge transferred from the compensation capacitor C c to the basic capacitor C b , so that the upper and lower plates of the compensation capacitor C c can be controlled
  • the voltage difference is the same, so as to eliminate the difference in capacitance when the metal oxide semiconductor capacitor is used as the compensation capacitor.
  • the absolute values of the first voltage and the second voltage are equal.
  • the charges involved are all positive charges.
  • step S300 when the compensation capacitor compensates for the basic capacitor, the operational amplifier detects and outputs the amount of change of the basic capacitor.
  • the third switch S3 is turned off.
  • the operational amplifier AMP is activated.
  • the variation of the basic capacitor C b detects and outputs the detection signal Vo at the same time.
  • the compensation capacitor C c is a metal oxide semiconductor capacitor. Further, the compensation capacitor C c may also include other capacitors with higher capacitance per unit area.
  • the touch detection circuit provided by the embodiment of the present invention uses NCAP as a compensation capacitor, so that the chip area is greatly reduced (for example, about 50%), and the sensitivity of the touch detection circuit is improved.
  • the miniaturization of the chip saves manufacturing costs.
  • the present invention also discloses a touch display device, which includes a display panel and a touch detection circuit as described in FIG. 2 and FIG. 3.
  • the touch detection circuit outputs the detection signal Vo according to the amount of change of the basic capacitance C c , so as to realize the recognition operation.
  • the display panel includes: a cathode ray tube display panel, a digital light processing display panel, a liquid crystal display panel, a light emitting diode display panel, an organic light emitting diode display panel, a quantum dot display panel, a Mirco-LED display panel, Mini-LED display panel, field emission display panel, plasma display panel, electrophoretic display panel or electrowetting display panel
  • the touch display device made by using the above-mentioned touch detection circuit has the advantages of small size, low cost, and high detection sensitivity.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Human Computer Interaction (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electronic Switches (AREA)
  • Position Input By Displaying (AREA)

Abstract

一种触摸检测电路、触控显示装置以及触摸检测方法，所述触摸检测电路，包括：运算放大器，补偿电容，以及与补偿电容相连接的多个开关，所述多个开关连通或断开所述补偿电容与反相输入端、第一偏置端、第二偏置端及第三偏置端的电连接，以提高电容感应信号的变化灵敏度，其中，所述补偿电容包括金属氧化物半导体电容。所述触摸检测电路可以提高灵敏度，同时实现芯片的小型化，降低芯片成本。

Description

触摸检测电路、触控显示装置以及触摸检测方法
本申请要求了2019年4月26日提交的、申请号为201910343219.4、发明名称为“触摸检测电路、触控显示装置以及触摸检测方法”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明涉及触控技术领域，具体涉及一种触摸检测电路、触控显示装置以及触摸检测方法。
背景技术
现有电容式触控装置检测方法，有基于自电容检测和互电容检测两种基本方案，两种基本方案都是通过检测有导体(如人的手指)靠近容性触摸装置所引起的微小电容变化来实现识别操作的。而一般情况下，由导体靠近装置所引起的电容变化量远小于装置具有的被测电容的大小，这些被测电容包括屏幕自身所具有的电容以及屏幕寄生电容。由于被测电容的存在，限制了检测电路的有效检测范围，从而限制了对微小电容变化检测灵敏度的提高。
为解决这一技术问题，现有技术中常采用在原有触摸检测电路中增加补偿电容的方法，通过控制补偿电容的充电、放电过程，将被测电容的电量降低一预定电量，使得被测电容上的电容变化量相对于无补偿电容时的电容变化量增大，进而提高检测电路的灵敏度。
而现有技术中补偿电容大多采用MIM(Metal-Insulator-Metal，金属-绝缘层-金属)电容或者MOM(Metal-Oxide-Metal，金属-氧化物-金属)电容来对屏幕的基础电容进行补偿。但是MIM电容或者MOM电容有个很大的问题就是它们的单位面积容值很小，如果遇到基础电容很大的屏幕，就会需要非常多的MIM电容或者MOM电容，这样占用的芯片面积较大，不利于芯片的小型化，且增加了芯片的制造成本。因而，在实现提高检测电路的灵敏度的基础上，实现芯片的小型化就成了本领域的技术人员需要解决的问题。
发明内容
为了解决上述技术问题，本发明提供了一种触摸检测电路、触控显示装置以及触摸检测方法，可以减小芯片面积，降低芯片成本。
根据本发明提供的一种触摸检测电路，其特征在于，包括：运算放大器，包括接收电容感应信号的反相输入端，接收共模电压的同相输入端，以及提供检测信号的输出端；补偿电容， 对所述电容感应信号进行补偿以调高信号灵敏度；以及多个开关，与补偿电容相连接，以连通或断开所述补偿电容与所述反相输入端、第一偏置端、第二偏置端及第三偏置端的电连接，其中，所述多个开关包括连接在所述反相输入端和所述补偿电容第一端之间的第九开关，所述多个开关用于在所述第九开关关断时实现对所述补偿电容上下极板的充电/放电，平衡所述补偿电容的上下极板压差。
优选地，所述补偿电容包括金属氧化物半导体电容。
优选地，所述触摸检测电路还包括：基础电容，所述基础电容的第一端通过第二开关连接所述运算放大器的反相输入端，第二端接地；电压源，所述电压源经由第一开关连接至所述基础电容的第一端，用于为所述基础电容充电；第三开关，所述第三开关串联在所述运算放大器的反向输入端和所述运算放大器的输出端之间；第一电容，所述第一电容与所述第三开关并联连接。
优选地，所述多个开关还包括：第四开关，所述第四开关连接于所述补偿电容的第一端与所述第一偏置端之间；第五开关，所述第五开关连接于所述补偿电容的第一端与所述第三偏置端之间；第六开关，所述第六开关连接于所述补偿电容的第二端与所述第一偏置端之间；第七开关，所述第七开关连接于所述补偿电容的第二端与所述第三偏置端之间；第八开关，所述第八开关连接于所述补偿电容的第二端与所述第二偏置端之间。
优选地，所述第一偏置端为正电压源偏置端，所述第二偏置端为负电压源偏置端，和所述第三偏置端为模拟地偏置端。
优选地，在激励信号的上升沿触发前的第一时间段，闭合第四开关和第七开关，将所述补偿电容充电至第一电压，在所述激励信号的上升沿触发后的第一时间段，闭合第六开关和第九开关，所述补偿电容上的电荷向基础电容上转移，在所述激励信号的下降沿触发前的第一时间段，闭合第五开关和第七开关，对所述补偿电容的上下极板进行放电，以及在所述激励信号的下降沿触发后的第一时间段，闭合第八开关和第九开关，将所述补偿电容充电至第二电压，同时所述基础电容上的电荷向所述补偿电容上转移。
优选地，所述正电压源偏置端的输出电压与所述负电压源偏置端的输出电压的电压大小相等，电压极性相反。
优选地，所述第一电压与所述第二电压的绝对值相等。
优选地，所述电压源输出电压可在正电压和负电压间切换。
根据本发明提供的一种触控显示装置，其特征在于，包括：显示面板，以及权利要求1至9中任一项所述的触摸检测电路，所述触摸检测电路用于提供检测信号。
优选地，所述显示面板包括：阴极射线管显示面板、数字光处理显示面板、液晶显示面板、 发光二极管显示面板、有机发光二极管显示面板、量子点显示面板、Mirco-LED显示面板、Mini-LED显示面板、场发射显示面板、电浆显示面板、电泳显示面板或电润湿显示面板。
根据本发明提供的一种触摸检测方法，其特征在于，包括：在激励信号的上升沿或下降沿触发前的第一时间段，由电压源根据所述激励信号对基础电容充电；在激励信号的上升沿或下降沿触发后的第一时间段，由补偿电容对所述基础电容进行补偿，其中，所述补偿电容对所述基础电容补偿时，由多个偏置端根据所述激励信号对所述补偿电容的上下极板进行充电/放电。
优选地，所述多个偏置端包括：正电压源偏置端、负电压源偏置端以及模拟地偏置端。
优选地，所述补偿电容包括金属氧化物半导体电容。
优选地，所述激励信号为高电平时，所述电压源输出电压为正电压，所述激励信号为低电平时，所述电压源输出电压为负电压。
优选地，所述触摸检测方法还包括：所述补偿电容对所述基础电容进行补偿时，由运算放大器对所述基础电容的变化量进行检测输出。
优选地，对所述基础电容的补偿方法包括：在所述激励信号的上升沿触发前的第一时间段，将所述补偿电容充电至第一电压；在所述激励信号的上升沿触发后的第一时间段，所述补偿电容上的电荷向所述基础电容上转移；在所述激励信号的下降沿触发前的第一时间段，对所述补偿电容的上下极板进行放电；在所述激励信号的下降沿触发后的第一时间段，将所述补偿电容充电至第二电压，同时所述基础电容上的电荷向所述补偿电容上转移。
优选地，所述电荷为正电荷。
优选地，所述第一电压与所述第二电压的绝对值相等。
本发明的有益效果是：本发明提供了一种触摸检测电路、触控显示装置以及触摸检测方法，通过采样金属氧化物半导体电容作为基础电容来对触摸检测电路中的基础电容进行补偿，有效地减小了芯片面积，又由于金属氧化物半导体电容的单位面积容值是MIM电容的两倍，也在一定程度上减小了补偿电容的面积，极大的降低了芯片成本。
通过设置相应的开关电路将NCAP电容的两端连接至多个偏置源，并通过该多个偏置源对NCAP电容的上下极板进行充电/放电，有效地消除了NCAP上下极板压差不一样时容值存在的差异。
本发明在基础电容C b正/负电压充电转换期间，将补偿电容C c的上极板和下极同时接模拟地，这样可以释放补偿电容C c的上极板和下极板上的残存电荷，进一步提高补偿电容C c对基础电容C b的补偿效果。
附图说明
通过以下参照附图对本发明实施例的描述，本发明的上述以及其他目的、特征和优点将更 为清楚。
图1示出根据现有技术的触摸检测电路的结构示意图；
图2示出本发明实施例提供的触摸检测电路的结构示意图；
图3示出本发明实施例提供的触摸检测电路的控制时序图；
图4示出本发明实施例提供的触摸检测方法的流程图；
图5示出本发明实施例提供的基础电容补偿方法的流程图。
具体实施方式
为了便于理解本发明，下面将参照相关附图对本发明进行更全面的描述。附图中给出了本发明的较佳实施例。但是，本发明可以通过不同的形式来实现，并不限于本文所描述的实施例。相反的，提供这些实施例的目的是使对本发明的公开内容的理解更加透彻全面。
除非另有定义，本文所使用的所有的技术和科学术语与属于本发明的技术领域的技术人员通常理解的含义相同。本文在本发明的说明书中所使用的术语只是为了描述具体的实施例的目的，不是旨在于限制本发明。
下面，参照附图对本发明进行详细说明。
图1示出根据现有技术的触摸检测电路的结构示意图。
如图1所示，触摸检测电路包括：基础电容C b、第一电容C f、补偿电容C c、运算放大器AMP、第一开关S1、第二开关S2、第三开关S3、第四开关S4以及第五开关S5，其中，基础电容C b对应为每个像素点的对地电容。
基础电容C b的第一端同时连接至第一开关S1的第一端和第二开关S2的第一端，基础电容C b的第二端接地；第一开关S1的第二端连接至电压源；第二开关S2的第二端连接至运算放大器AMP的反相输入端；第三开关S3连接至运算放大器AMP的输出端和反相输入端之间；第一电容C f与第三开关S3并联连接；运算放大器AMP的同相输入端接收共模电压VCM，运算放大器AMP的输出端用于输出检测信号Vo；补偿电容C c的第一端连接至运算放大器AMP反相输入端，补偿电容C c的第二端分别与第四开关S4的第一端和第五开关S5的第一端连接，第四开关S4的第二端和第五开关S5的第二端分别连接至第一补偿电压源和第二补偿电压源。
图1所示触摸检测电路的结构图中，由于触摸引起的基础电容C b变化量等效为与基础电容C b并联连接的触摸电容△C。其中，电压源、第一补偿电压源以及第二补偿电压源包括选自正电压源VDD和负电压源VSS中的任一种。
图1所示的触摸检测电路包括ψ1和ψ2两个时期，其中在ψ1期间主要对基础电容C b进行充电，在ψ2期间主要对基础电容C b进行补偿。同时，图1的电路图中标号ψ1和ψ2表示：在ψ1期间，ψ1所对应的开关闭合，ψ2所对应的开关断开；和在ψ2期间，ψ1所对应的开关断开，ψ2 所对应的开关闭合。
在第一期间ψ1内，第一开关S1、第三开关S3以及第四开关S4均闭合，第二开关S2以及第五开关S5均断开。基础电容C b经由第一开关S1开始充电，补偿电容C c经由第四开关S4开始充电，电压源例如为正电压源VDD，对应地，第一补偿电压源例如为负电压源VSS。充电完成后，基础电容C b两端电压对应为VCC，补偿电容C c两端电压对应为VSS。此时运算放大器AMP接成一个单位增益缓冲器，由单位增益缓冲器的相关特性可知，运算放大器AMP的输出端电压等于同相输入端电压，均对应为共模电压VCM。
在第二期间ψ2内，第一开关S1、第三开关S3以及第四开关S4均关断，第二开关S2和第五开关S5闭合，使得运算放大器AMP工作在线性区，此时把运算放大器AMP的同相输入端和反相输入端视为等电位，这一特性称为虚假短路，简称为虚短。由于运算放大器AMP的这一特性，此时，运算放大器AMP的同相输入端和反相输入端电压均对应为共模电压VCM。
触摸检测电路中若无第四开关S4、第五开关S5以及补偿电容Cc，在此阶段，基础电容C b和第一电容C f之间发生电荷的转移，直到使得运算放大器AMP的同相输入端和反相输入端等电位。在此过程中，造成运算放大器AMP输出检测信号Vo的变化，若第一期间ψ1内检测信号Vo对应为Vo ψ1，第二期间ψ2内检测信号Vo对应为Vo ψ2，则检测信号Vo变化量△Vo对应为：
Figure PCTCN2019101023-appb-000001
根据电荷守恒定律，可得：
Figure PCTCN2019101023-appb-000002
运算放大器AMP的输出端连接至模数转换电路，该模数转换电路用于根据检测信号Vo变化量得到触摸电容△C。
由于基础电容C b电容值太大(最大可达上百pF)，而在实际应用时只希望获得的触摸电容△C电容值(通常只有1pF左右)，这就会造成检测信号Vo变化量△Vo太小，降低检测灵敏度。
现有技术中的检测电路由于增加了第四开关S4、第五开关S5以及补偿电容C c，第二补偿电压源例如为VDD，第五开关S5闭合，使得补偿电容C c两端电压对应为VDD-VSS，基础电容C b和补偿电容C c之间发生电荷的转移，基础电容C b的电量降低，使得基础电容C b的电容变化量(即触摸电容△C)相对于无补偿电容C c时增大，进而提高检测电路的灵敏度。
现有技术中，虽然可以提高检测电路的灵敏度，但是其补偿电容大多采用MIM电容或者MOM电容来对屏幕的基础电容进行补偿。但是MIM电容或者MOM电容有个很大的问题就是它们的单位面积容值很小，如果遇到基础电容很大的屏幕，就会需要非常多的MIM电容或者MOM电容，这样占用的芯片面积较大，不利于芯片的小型化，且增加了芯片的制造成本。
图2示出本发明实施例提供的触摸检测电路的结构示意图。
如图2所示，本实施例中，触摸检测电路包括：基础电容C b、第一电容C f、补偿电容C c、多个开关、运算放大器AMP、第一开关S1、第二开关S2以及第三开关S3。
运算放大器AMP，包括接收电容感应信号的反相输入端，接收共模电压VCM的同相输入端，以及提供检测信号的输出端Vo。
本实施例中，运算放大器AMP的输出端连接至模数转换电路，该模数转换电路用于根据检测信号Vo变化量得到触摸电容△C。
本实施例中，第三开关S3连接在运算放大器AMP的输出端和反相输入端之间；第一电容C f与第三开关S3并联连接。
补偿电容C c，对电容感应信号进行补偿以提高信号的灵敏度。
本实施例中，补偿电容C c的第一端经由第二开关S2连接至基础电容C b的第一端，补偿电容C c用于对基础电容C b进行补偿。
优选地，本实施例中，补偿电容C c采用NCAP电容(即N阱电容器或金属氧化物半导体电容)，该N阱电容器的单位面积容值是传统金属绝缘层金属电容器的两倍，它包含有：根据基本掺杂类型掺杂的基本掺杂区；至少一个掺杂连接区，其优选邻接基本掺杂区并且根据基本掺杂类型掺杂，并且其最大掺杂剂浓度比基本掺杂区中的最大掺杂剂浓度高；以及离基本掺杂区一定距离布置的电极区，该电极区根据MOS晶体管(金属氧化物半导体)的结构还称作为栅极区，以及布置在电极区和基本掺杂区之间的电介质。
进一步地，补偿电容C c还可包括具有较高的单位面积容值的其它电容器。
多个开关，与补偿电容C c相连接，该多个开关用于连通或断开补偿电容C c与运算放大器AMP的反相输入端、第一偏置端、第二偏置端及第三偏置端的电连接。
本实施例中，该多个开关包括连接于补偿电容C c的第一端与运算放大器AMP的反相输入端之间的第九开关S9。第九开关S9可作为转向开关，用于在该第九开关S9导通时连通补偿电容C c与运算放大器AMP的反相输入端，并实现补偿电容C c对基础电容C b的双向(电荷转移方向)补偿；以及该多个开关用于在第九开关S9关断时，实现对补偿电容C c上下极板的充电/放电，平衡所述补偿电容C c的上下极板压差。
进一步地，多个开关还包括第四开关S4、第五开关S5、第六开关S6、第七开关S7以及第八开关S8，该多个开关用于在导通时将补偿电容C c的第一端和第二端分别连接至多个偏置端，以平衡补偿电容C c的上下极板压差，进一步消除采用金属氧化物半导体电容为补偿电容时，补偿电容C c的容值差异。
进一步地，该多个开关的导通受控于激励信号。
其中，第四开关S4连接于补偿电容C c的第一端与第一偏置端(正电压源)VDP之间；第五开关S5连接于补偿电容C c的第一端与第三偏置端(模拟地)VSS之间；第六开关S6连接于补偿电容C c的第二端与第一偏置端之间(正电压源)VDP；第七开关S7连接于补偿电容C c的第二端与第三偏置端(模拟地)VSS之间；第八开关S8连接于补偿电容C c的第二端与第二偏置端(负电压源)VDN之间。
本实施例中，补偿电容C c、多个开关以及多个偏置端可组成补偿模块100，该补偿模块100主要用于实现对外接信号的补偿。可以理解的是，该补偿模块100也可适用于其它电路。
基础电容C b，对应为每个像素点的对地电容。其第一端通过第二开关S2连接至运算放大器AMP的反相输入端，第二端接地。
电压源通过第一开关S1连接至基础电容C b的第二端，该电压源包括选自正电压源VDP和负电压源VDN中的任一种。
优选地，本实施例中，电压源输出电压可根据激励信号在正电压和负电压间切换，如当激励信号为高电平时，电压源输出正电压VDP，当激励信号为低电平时，电压源输出负电压VDN。
图2所示触摸检测电路的结构图中，由于触摸引起的基础电容C b变化量等效为与基础电容C b并联连接的触摸电容△C，对应电容感应信号。
优选地，本实施例中，正电压源VDP与负电压源VDN的电压绝对值相等，即正电压源VDP与负电压源VDN的电压大小相等，电压极性相反。
下面请参考图3对本实施例触摸检测电路工作原理做进一步说明。图3示出本发明实施例提供的触摸检测电路的控制时序图。
需要说明的是，本实施例中，如图3所示，触摸检测电路的工作时序分为第一时间段t1、第二时间段t2、第三时间段t3以及第四时间段t4。其中，t1和t3时间段对应基础电容的充电时间段，t2和t4时间段对应对基础电容进行电荷补偿的时间段。
参照图3，本实施例中，以激励信号的上升沿触发前的第一时间段表示第一时间段t1；以激励信号的上升沿触发后的第一时间段表示第二时间段t2；以激励信号的下降沿触发前的第一时间段表示第三时间段t3；及以激励信号的下降沿触发后的第一时间段表示第四时间段t4。进一步地，在第一时间段t1与第二时间段t2过渡的时间点，激励信号上升沿触发，在第三时间段t3与及第四时间段t4过渡的时间点，激励信号下降沿触发。
在每个阶段所对应的时序图中，针对开关S4到S9对应的控制信号，其中，高电平信号对应其相应开关的闭合状态，低电平信号对应其相应开关的断开状态。
结合图2，触摸检测电路的工作原理具体如下：
在激励信号的上升沿触发前的第一时间段t1内，激励信号为低电平，电压源切换为负电压源 VDN。此时第一开关S1和第三开关S3闭合，第二开关S2断开，基础电容C b经由第一开关S1开始负压充电，充电完成后，其两端的第一电压对应为VDN。
同时，第四开关S4和第七开关S7闭合，第五开关S5、第六开关S6和第八开关S8断开，补偿电容C c的上极板经由第四开关S4接正电压源VDP，下极板经由第七开关S7接模拟地VSS，正电压源VDP对补偿电容C c的上极板开始充电，充电完成后，其两端电压对应为VDP，且此时补偿电容C c上的电荷为C c*(VDP-VSS)。
在激励信号的上升沿触发后的第一时间段t2内，激励信号为高电平，和电压源切换为正电压源VDP。此时第二开关S2闭合，第一开关S1和第三开关S3断开，基础电容C b不再充电，和基础电容C b的第一端通过第二开关S2连接节点VIN。
同时，第六开关S6和第九开关S9闭合，第四开关S4、第五开关S5、第七开关S7和第八开关S8断开。补偿电容C c的上极板经由第九开关S9连接节点VIN(节点VIN的电压也是VDP)，和补偿电容C c的下极板经由第六开关S6接正电压源VDP。此时补偿电容C c上的电荷全部转移到节点VIN上，并通过节点VIN向基础电容C b转移。因此，转移的电荷为：Q 1＝VDP*Cc。
在激励信号的下降沿触发前的第一时间段t3内，激励信号为高电平不变，电压源为正电压源VDP。此时第一开关S1和第三开关S3闭合，第二开关S2断开，基础电容C b经由第一开关S1开始正压充电，和充电完成后，其两端的第二电压对应为VDP。
同时，第五开关S5和第七开关S7闭合，第四开关S4、第六开关S6、第八开关S8和第九开关S9断开，补偿电容C c的上极板和下极板分别经由第五开关S5和第七开关S7接模拟地VSS，故此时补偿电容C c上的电荷为零，可以释放补偿电容C c的上极板和下极板上残存的电荷，进一步提高补偿电容C c对基础电容C b的补偿效果。
在激励信号的下降沿触发后的第一时间段t4内，激励信号为低电平，电压源切换为负电压源VDN。此时第二开关S2闭合，第一开关S1和第三开关S3断开，基础电容C b不再充电，和基础电容C b的第一端通过第二开关S2连接节点VIN。
同时，第八开关S8和第九开关S9闭合，第四开关S4、第五开关S5、第六开关S6和第七开关S7断开，补偿电容C c的上极板经由第九开关S9接节点VIN(此时节点VIN的电压也是VSS)，并通过第二开关S2连接基础电容C b的第一端，和补偿电容C c的下极板经由第八开关S8接负电压源VDN。此时VDN对补偿电容C c的下极板开始充电，补偿电容C c上的电荷为C c*(VSS-VDN)。由于补偿电容C c上的电荷是由基础电容C b经由节点VIN上转移而来，因此，此时转移到补偿电容C c上的电荷为：Q 2＝(-VDN*C c)。
在本发明实施例中，正电压源VDP与负电压源VDN的绝对值相等，故VDP＝(-VDN)。所以，在激励信号的上升沿触发后的第一时间段内从补偿电容C c转移到节点VIN上的电荷与在激励信 号的下降沿触发后的第一时间段内从节点VIN转移到补偿电容C c上的电荷是相等的，这样可以控制补偿电容C c上下极板的压差相同，消除容值差异。
优选地，第一电压VDN与第二电压VDP的绝对值相等，电压极性相反。
本实施中，上述转移的电荷均为正电荷。
在本实施例中，一方面，基础电容C b和补偿电容C c之间发生的电荷的转移，可以使得基础电容C b的电量降低，再由公式(1.2)可知，基础电容C b的电容变化量(即触摸电容△C)相对于无补偿电容C c时增大，提高了检测电路的灵敏度。同时，本发明在基础电容C b正/负电压充电转换期间，可以释放补偿电容C c的上极板和下极板上残存的电荷，进一步提高补偿电容C c对基础电容C b的补偿效果。
另一方面，本发明实施例在触摸检测电路中采用NCAP电容(N阱电容器或金属氧化物半导体电容)作为补偿电容C c，有效地减小了芯片的面积，降低了芯片成本。
图4示出本发明实施例提供的触摸检测方法的流程图。图5示出本发明实施例提供的基础电容补偿方法的流程图。
如图4所示，可参照图2进行理解，本实施例中，触摸检测方法主要对触摸检测电路执行步骤S100至步骤S300。
在步骤S100中，在激励信号的上升沿或下降沿触发前的第一时间段内，由电压源根据激励信号对基础电容充电。
本实施例中，在激励信号的上升沿或下降沿触发前的第一时间段内，第一开关S1闭合，电压源通过第一开关S1给基础电容C b充电。同时第二开关S2断开，补偿电容C c不对基础电容C b进行电荷补偿，和第三开关S3闭合，运算放大器AMP不工作。
进一步地，电压源的电压极性由激励信号决定：如当激励信号为高电平时，电压源对基础电容C b进行正电压VDP充电，当激励信号为低电平时，电压源对基础电容C b进行负电压VDN充电。
在步骤S200中，在激励信号的上升沿或下降沿触发后的第一时间段内，由补偿电容对基础电容进行补偿。
本实施例中，在激励信号的上升沿或下降沿触发后的第一时间段内，当基础电容C b充电完成后，会并断开第一开关S1和第三开关S3，同时闭合第二开关S2，并执行步骤S210至步骤S240，由补偿电容C c对基础电容C b进行补偿。
进一步地，在补偿电容对基础电容补偿时，由多个偏置端根据激励信号对补偿电容的上下极板进行充电/放电。其中，多个偏置端包括：正电压源偏置端、负电压源偏置端以及模拟地偏置端。
如图5所示，本实施例中，补偿电容对基础电容的补偿方法包括：
在步骤S210中，在激励信号的上升沿触发前的第一时间段内，将补偿电容充电至第一电压。
本实施例中，在激励信号的上升沿触发前的第一时间段内，激励信号为低电平，电压源对基础电容C b进行负电压VDN充电，同时闭合第四开关S4和第七开关S7，对补偿电容C c进行正电压充电，以使得补偿电容C c两端的电压差为第一电压VDP。
在步骤S220中，在激励信号的上升沿触发后的第一时间段内，补偿电容上的电荷向基础电容上转移。
本实施例中，在激励信号的上升沿触发后的第一时间段内，基础电容C b充电完成，其上极板电压为VDN。此时激励信号的上升沿触发，并断开第一开关S1和第三开关S3，同时闭合第二开关S2，由补偿电容C c对基础电容C b进行补偿。
进一步地，补偿电容C c充电完成后，其上极板电压为VDP，此时断开第四开关S4和第七开关S7，同时闭合第六开关S6和第九开关S9，使得补偿电容C c上极板的电荷通过第九开关S9和第二开关S2转移到基础电容C b上，完成对基础电容C b的补偿。
在步骤S230中，在激励信号的下降沿触发前的第一时间段内，对补偿电容的上下极板进行放电。
本实施例中，在激励信号的下降沿触发前的第一时间段内，激励信号为高电平，此时断开第二开关S2，闭合第一开关S1和第三开关S3，由电压源通过第一开关S1对基础电容C b进行正电压充电。与此同时，会断开第六开关S6和第九开关S9，并闭合第五开关S5和第七开关S7，将补偿电容C c的上下极板均连接模拟地VSS，释放补偿电容C c的上下极板上的残存电荷。
在步骤S240中，在激励信号的下降沿触发后的第一时间段内，将补偿电容充电至第二电压，同时基础电容上的电荷向补偿电容上转移。
本实施例中，在激励信号的下降沿触发后的第一时间段内，基础电容C b充电完成，其上极板电压为VDP。此时激励信号的下降沿触发，断开第一开关S1和第三开关S3，同时闭合第二开关S2，由补偿电容C c对基础电容C b进行补偿。
进一步地，在第二开关S2闭合时，补偿电容C c充电荷释放结束，其上极板电压为零，此时断开第五开关S5和第七开关S7，并闭合第八开关S8和第九开关S9，对补偿电容C c进行负电压充电。补偿电容C c上极板上电荷为基础电容C b上极板的电荷通过第二开关S2和第九开关S9转移而来，因此，在对补偿电容C c进行充电时，补偿电容C c也同时在对基础电容C b进行补偿。
补偿电容C c充电完成后，其上下极板两端的电压差为第二电压VDN。
优选地，本实施例中，补偿电容C c对基础电容C b进行补偿时，电荷存在两个方向的转移， 因为本实施例中正电压源VDP与负电压源VDN的电压大小相等，极性相反，所以在进行电荷转移时，从基础电容C b转移到补偿电容C c上的电荷与补偿电容C c转移到基础电容C b上的电荷时相等的，这样可以控制补偿电容C c上下极板的电压压差相同，从而消除采用金属氧化物半导体电容作为补偿电容时的容值差异。
优选地，第一电压与第二电压的绝对值相等。
优选地，上述描述中，所涉及的电荷均为正电荷。
在步骤S300中，补偿电容对基础电容进行补偿时，由运算放大器对基础电容的变化量进行检测输出。
本实施例中，当补偿电容C c对基础电容C b进行补偿时，会断开第三开关S3，此时运算放大器AMP启动，通过运算放大器AMP的虚短特性，可以对基础电容的变化量C b进行检测，同时输出检测信号Vo。
优选地，补偿电容C c为金属氧化物半导体电容。进一步地，补偿电容C c还可包括具有较高的单位面积容值的其它电容器。
本发明实施例提供的触摸检测电路相对于现有技术而言，由于使用了NCAP做补偿电容，使得芯片的面积大大减少(如约为50％)，在实现提高触摸检测电路灵敏度的基础上实现了芯片的小型化，节省了制造成本。
本发明还公开了一种触控显示装置，该触控显示装置包括显示面板，以及如图2和图3所描述的触摸检测电路。在该触控显示装置中，由触摸检测电路根据基础电容C c的变化量输出检测信号Vo，从而实现识别操作。
优选地，本实施例中，显示面板包括：阴极射线管显示面板、数字光处理显示面板、液晶显示面板、发光二极管显示面板、有机发光二极管显示面板、量子点显示面板、Mirco-LED显示面板、Mini-LED显示面板、场发射显示面板、电浆显示面板、电泳显示面板或电润湿显示面板
本实施例中，采用上述触摸检测电路制成的触控显示装置，具有体积小，成本低，而且检测灵敏度高等的优点。
应当说明的是，在本文中，所含术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的过程、方法、物品或者设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种过程、方法、物品或者设备所固有的要素。在没有更多限制的情况下，由语句“包括一个……”限定的要素，并不排除在包括所述要素的过程、方法、物品或者设备中还存在另外的相同要素。
最后应说明的是：显然，上述实施例仅仅是为清楚地说明本发明所作的举例，而并非对实施方式的限定。对于所属领域的普通技术人员来说，在上述说明的基础上还可以做出其它不同 形式的变化或变动。这里无需也无法对所有的实施方式予以穷举。而由此所引申出的显而易见的变化或变动仍处于本发明的保护范围之中。

Claims (19)

  1. 一种触摸检测电路，其特征在于，包括：
    运算放大器，包括接收电容感应信号的反相输入端，接收共模电压的同相输入端，以及提供检测信号的输出端；
    补偿电容，对所述电容感应信号进行补偿以调高信号灵敏度；以及
    多个开关，与补偿电容相连接，以连通或断开所述补偿电容与所述反相输入端、第一偏置端、第二偏置端及第三偏置端的电连接，
    其中，所述多个开关包括连接在所述反相输入端和所述补偿电容第一端之间的第九开关，所述多个开关用于在所述第九开关关断时实现对所述补偿电容上下极板的充电/放电，平衡所述补偿电容的上下极板压差。
  2. 根据权利要求1所述的触摸检测电路，其特征在于，所述补偿电容包括金属氧化物半导体电容。
  3. 根据权利要求1所述的触摸检测电路，其特征在于，所述触摸检测电路还包括：
    基础电容，所述基础电容的第一端通过第二开关连接所述运算放大器的反相输入端，第二端接地；
    电压源，所述电压源经由第一开关连接至所述基础电容的第一端，用于为所述基础电容充电；
    第三开关，所述第三开关串联在所述运算放大器的反向输入端和所述运算放大器的输出端之间；
    第一电容，所述第一电容与所述第三开关并联连接。
  4. 根据权利要求1所述的触摸检测电路，其特征在于，所述多个开关还包括：
    第四开关，所述第四开关连接于所述补偿电容的第一端与所述第一偏置端之间；
    第五开关，所述第五开关连接于所述补偿电容的第一端与所述第三偏置端之间；
    第六开关，所述第六开关连接于所述补偿电容的第二端与所述第一偏置端之间；
    第七开关，所述第七开关连接于所述补偿电容的第二端与所述第三偏置端之间；
    第八开关，所述第八开关连接于所述补偿电容的第二端与所述第二偏置端之间。
  5. 根据权利要求1或4所述的触摸检测电路，其特征在于，所述第一偏置端为正电压源偏置端，所述第二偏置端为负电压源偏置端，和所述第三偏置端为模拟地偏置端。
  6. 根据权利要求4所述的触摸检测电路，其特征在于，
    在激励信号的上升沿触发前的第一时间段，闭合第四开关和第七开关，将所述补偿电容充电至第一电压，
    在所述激励信号的上升沿触发后的第一时间段，闭合第六开关和第九开关，所述补偿电容上的电荷向基础电容上转移，
    在所述激励信号的下降沿触发前的第一时间段，闭合第五开关和第七开关，对所述补偿电容的上下极板进行放电，以及
    在所述激励信号的下降沿触发后的第一时间段，闭合第八开关和第九开关，将所述补偿电容充电至第二电压，同时所述基础电容上的电荷向所述补偿电容上转移。
  7. 根据权利要求5所述的触摸检测电路，其特征在于，所述正电压源偏置端的输出电压与所述负电压源偏置端的输出电压的电压大小相等，电压极性相反。
  8. 根据权利要求6所述的触摸检测电路，其特征在于，所述第一电压与所述第二电压的绝对值相等。
  9. 根据权利要求3所述的触摸检测电路，其特征在于，所述电压源输出电压可在正电压和负电压间切换。
  10. 一种触控显示装置，其特征在于，包括：
    显示面板，以及
    权利要求1至9中任一项所述的触摸检测电路，所述触摸检测电路用于提供检测信号。
  11. 根据权利要求10所述的触控显示装置，其特征在于，所述显示面板包括：阴极射线管显示面板、数字光处理显示面板、液晶显示面板、发光二极管显示面板、有机发光二极管显示面板、量子点显示面板、Mirco-LED显示面板、Mini-LED显示面板、场发射显示面板、电浆显示面板、电泳显示面板或电润湿显示面板。
  12. 一种触摸检测方法，其特征在于，包括：
    在激励信号的上升沿或下降沿触发前的第一时间段，由电压源根据所述激励信号对基础电容充电；
    在激励信号的上升沿或下降沿触发后的第一时间段，由补偿电容对所述基础电容进行补偿，其中，所述补偿电容对所述基础电容补偿时，由多个偏置端根据所述激励信号对所述补偿电容的上下极板进行充电/放电。
  13. 根据权利要求12所述的触摸检测方法，其特征在于，所述多个偏置端包括：正电压源偏置端、负电压源偏置端以及模拟地偏置端。
  14. 根据权利要求12所述的触摸检测方法，其特征在于，所述补偿电容包括金属氧化物半导体电容。
  15. 根据权利要求12所述的触摸检测方法，其特征在于，所述激励信号为高电平时，所述电压源输出电压为正电压，所述激励信号为低电平时，所述电压源输出电压为负电压。
  16. 根据权利要求12所述的触摸检测方法，其特征在于，所述触摸检测方法还包括：所述补偿电容对所述基础电容进行补偿时，由运算放大器对所述基础电容的变化量进行检测输出。
  17. 根据权利要求12所述的触摸检测方法，其特征在于，对所述基础电容的补偿方法包括：
    在所述激励信号的上升沿触发前的第一时间段，将所述补偿电容充电至第一电压；
    在所述激励信号的上升沿触发后的第一时间段，所述补偿电容上的电荷向所述基础电容上转移；
    在所述激励信号的下降沿触发前的第一时间段，对所述补偿电容的上下极板进行放电；
    在所述激励信号的下降沿触发后的第一时间段，将所述补偿电容充电至第二电压，同时所述基础电容上的电荷向所述补偿电容上转移。
  18. 根据权利要求17所述的触摸检测方法，其特征在于，所述电荷为正电荷。
  19. 根据权利要求17所述的触摸检测方法，其特征在于，所述第一电压与所述第二电压的绝对值相等。
PCT/CN2019/101023 2019-04-26 2019-08-16 触摸检测电路、触控显示装置以及触摸检测方法 WO2020215537A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
KR1020207036587A KR102491774B1 (ko) 2019-04-26 2019-08-16 터치 검출 회로, 터치 디스플레이 장치 및 터치 검출 방법
JP2020552722A JP7319291B2 (ja) 2019-04-26 2019-08-16 タッチ検出回路、タッチ表示装置及びタッチ検出方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201910343219.4 2019-04-26
CN201910343219.4A CN110196653B (zh) 2019-04-26 2019-04-26 触摸检测电路、触控显示装置以及触摸检测方法

Publications (1)

Publication Number Publication Date
WO2020215537A1 true WO2020215537A1 (zh) 2020-10-29

Family

ID=67752202

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/101023 WO2020215537A1 (zh) 2019-04-26 2019-08-16 触摸检测电路、触控显示装置以及触摸检测方法

Country Status (4)

Country Link
JP (1) JP7319291B2 (zh)
KR (1) KR102491774B1 (zh)
CN (1) CN110196653B (zh)
WO (1) WO2020215537A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112803941A (zh) * 2021-01-07 2021-05-14 深圳锐盟半导体有限公司 触控检测电路和耳机
CN112798872A (zh) * 2020-12-25 2021-05-14 南京邮电大学 一种触摸屏电容检测电路
CN114097180A (zh) * 2020-12-28 2022-02-25 深圳市汇顶科技股份有限公司 一种nfc设备

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021097727A1 (zh) * 2019-11-20 2021-05-27 深圳市汇顶科技股份有限公司 一种电容检测电路、触控装置、终端设备和电容检测方法
CN111245218B (zh) * 2020-01-14 2021-09-17 北京集创北方科技股份有限公司 开关控制电路、多路选择开关电路及其控制方法
CN111399679B (zh) * 2020-03-11 2022-04-08 北京集创北方科技股份有限公司 电容检测装置
CN112415604B (zh) * 2021-01-22 2021-06-18 深圳市汇顶科技股份有限公司 检测电路、芯片及相关电子装置
CN113204290B (zh) 2021-04-19 2022-12-30 深圳天德钰科技股份有限公司 信号补偿电路、触控控制电路及显示装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101676828A (zh) * 2008-09-19 2010-03-24 智原科技股份有限公司 应用于低操作电压的参考电流产生电路
CN102541367A (zh) * 2010-12-29 2012-07-04 比亚迪股份有限公司 一种电容式触控检测电路、检测装置及其检测方法
CN104049822A (zh) * 2014-06-18 2014-09-17 深圳贝特莱电子科技有限公司 一种触摸屏控制电路的检测系统
US20160378252A1 (en) * 2013-06-27 2016-12-29 Crucial Tec Co., Ltd. Apparatus and Method for Detecting Touch
CN108509094A (zh) * 2017-02-23 2018-09-07 麦孚斯公司 电容检测方法和使用该方法的电容检测装置

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI357501B (en) * 2008-03-25 2012-02-01 Raydium Semiconductor Corp Evaluation circuit for capacitance and method ther
US8982060B2 (en) * 2010-08-27 2015-03-17 Apple Inc. Touch and hover sensor compensation
CN103593097B (zh) * 2012-11-29 2017-03-01 敦泰科技有限公司 一种终端设备的触摸检测系统及终端设备
KR102251059B1 (ko) * 2014-10-06 2021-05-13 삼성전자주식회사 다단계 오프셋 커패시턴스 조정이 가능한 터치 디스플레이 장치
KR102198854B1 (ko) * 2014-11-05 2021-01-05 삼성전자 주식회사 터치 아날로그 프론트 엔드 및 이를 포함하는 터치 센서 컨트롤러
US10031620B2 (en) * 2016-06-30 2018-07-24 Stmicroelectronics Asia Pacific Pte Ltd Self-sensing touch panel
TWI621984B (zh) * 2016-12-02 2018-04-21 瑞鼎科技股份有限公司 電容値量測電路及電容値量測方法
CN106598370B (zh) * 2017-01-19 2024-03-15 北京集创北方科技股份有限公司 触摸检测电路及其触控装置
CN206877306U (zh) * 2017-04-12 2018-01-12 北京集创北方科技股份有限公司 感应电容测量装置
TWI685782B (zh) * 2017-10-11 2020-02-21 瑞鼎科技股份有限公司 電容式觸控感測電路及其電荷補償方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101676828A (zh) * 2008-09-19 2010-03-24 智原科技股份有限公司 应用于低操作电压的参考电流产生电路
CN102541367A (zh) * 2010-12-29 2012-07-04 比亚迪股份有限公司 一种电容式触控检测电路、检测装置及其检测方法
US20160378252A1 (en) * 2013-06-27 2016-12-29 Crucial Tec Co., Ltd. Apparatus and Method for Detecting Touch
CN104049822A (zh) * 2014-06-18 2014-09-17 深圳贝特莱电子科技有限公司 一种触摸屏控制电路的检测系统
CN108509094A (zh) * 2017-02-23 2018-09-07 麦孚斯公司 电容检测方法和使用该方法的电容检测装置

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112798872A (zh) * 2020-12-25 2021-05-14 南京邮电大学 一种触摸屏电容检测电路
CN112798872B (zh) * 2020-12-25 2023-08-08 南京邮电大学 一种触摸屏电容检测电路
CN114097180A (zh) * 2020-12-28 2022-02-25 深圳市汇顶科技股份有限公司 一种nfc设备
CN114097180B (zh) * 2020-12-28 2023-07-28 深圳市汇顶科技股份有限公司 一种nfc设备
CN112803941A (zh) * 2021-01-07 2021-05-14 深圳锐盟半导体有限公司 触控检测电路和耳机

Also Published As

Publication number Publication date
KR20210010580A (ko) 2021-01-27
CN110196653A (zh) 2019-09-03
KR102491774B1 (ko) 2023-01-27
CN110196653B (zh) 2020-09-11
JP2022507996A (ja) 2022-01-19
JP7319291B2 (ja) 2023-08-01

Similar Documents

Publication Publication Date Title
WO2020215537A1 (zh) 触摸检测电路、触控显示装置以及触摸检测方法
CN106598370B (zh) 触摸检测电路及其触控装置
US10845926B2 (en) Capacitance detecting circuit, touch device and terminal device
CN1908881B (zh) 感测电路和具有该感测电路的显示设备
CN104766584B (zh) 具有正反向扫描功能的goa电路
CN106997253B (zh) 集成触摸屏的显示装置
US20200220543A1 (en) Capacitive touch sensing circuit
WO2021036306A1 (zh) 电容感测装置
US10241629B2 (en) Filtering circuit and touch display device
TW201501003A (zh) 觸控裝置及感測補償方法
US20130177128A1 (en) Shift register and method thereof
CN110212880B (zh) 一种电荷放大器电路及其时序控制方法
CN105242804A (zh) 触控补偿电路、其补偿方法、触摸屏及显示装置
CN102545862B (zh) 开关电路
US8400420B2 (en) Image display system and method for controlling a touch panel thereof
KR102248984B1 (ko) 고감도 터치 센서
US11567603B2 (en) Capacitance detection circuit and input device
CN213987461U (zh) 基础电容补偿电路、芯片、触控显示器及信息处理装置
US20120001864A1 (en) Flat panel display apparatus with touch function and touch panel
Wang et al. Design and implementation of readout circuit on glass substrate for touch panel applications
TWI693545B (zh) 觸控晶片、觸控顯示裝置及資訊處理裝置
EP3493096B1 (en) Fingerprint sensor and terminal device
CN112558813A (zh) 一种基础电容补偿电路及方法
US10061426B2 (en) Self-capacitive touch display panel and driving method thereof
US20130278334A1 (en) Slew rate and bandwidth enhancement in reset

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2020552722

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19926469

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 20207036587

Country of ref document: KR

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19926469

Country of ref document: EP

Kind code of ref document: A1