Foreign objection detection sensing circuit for wireless power transmission systems

    公开(公告)号:US11152822B1

    公开(公告)日:2021-10-19

    申请号:US17037982

    申请日:2020-09-30

    IPC分类号: H02J50/60 H02J50/12

    摘要: A wireless-power-circuit is operable in transceiver-mode and Q-factor-measurement-mode, and includes a bridge coupled to a coil, and having an output coupled to a rectified-voltage node. An excitation circuit, when in Q-factor-measurement-mode, drives the coil with a pulsed signal. A protection circuit couples the coil to a first node when in Q-factor-measurement-mode and decouples the coil from the first node when in transceiver-mode. A Q-factor sensing circuit includes an amplifier having inputs coupled to the first node and a common mode voltage (Vcm), and generating an output signal having an output voltage. A comparator generates a comparison output indicating Vcm crossing of a voltage at the first terminal of the coil, a processing circuit generating an enable signal based upon the comparison output, and an analog-to-digital-converter, when enabled, digitizing the output voltage for use in calculating a Q-factor of the coil.

    TOUCH REJECTION FOR COMMUNICATION BETWEEN A TOUCH SCREEN DEVICE AND AN ACTIVE STYLUS
    3.
    发明申请
    TOUCH REJECTION FOR COMMUNICATION BETWEEN A TOUCH SCREEN DEVICE AND AN ACTIVE STYLUS 有权
    触控屏幕设备与主动式笔记本之间的通信触发阻止

    公开(公告)号:US20160266673A1

    公开(公告)日:2016-09-15

    申请号:US14641717

    申请日:2015-03-09

    CPC分类号: G06F3/044 G06F3/0416

    摘要: A touch panel includes capacitive sensing electrodes and a touch controller operates in a first operating mode to detect a touch location on the touch panel. In a second operating mode, the touch controller transmits a modulated data signal through the touch panel to an active stylus. Each electrode is driven by a line driver circuit. A control circuit selectively actuates first ones of the line driver circuits to pass the modulated data signal to corresponding first ones of the electrodes which do not pass through a region of the touch panel associated with the location of the detected touch. Simultaneously, the control circuit selectively actuates second ones of the line driver circuits, different from said first ones of the line driver circuits, to ground corresponding second ones of the electrodes which do pass through the region of the touch panel associated with the location of the detected touch.

    摘要翻译: 触摸面板包括电容感测电极,并且触摸控制器在第一操作模式下操作以检测触摸面板上的触摸位置。 在第二操作模式中,触摸控制器通过触摸面板将经调制的数据信号发送到活动触针。 每个电极由线路驱动电路驱动。 控制电路选择性地致动线路驱动电路中的第一线路,以将经调制的数据信号传递到不通过与检测到的触摸的位置相关联的触摸面板的区域的对应的第一电极。 同时,控制电路选择性地将不同于所述第一线路驱动器电路的线路驱动器电路中的第二线路驱动到接地的相应的第二电极,所述对应的第二电极通过与触摸面板的位置相关联的触摸面板的区域 检测到触摸。

    SYSTEM AND METHOD OF COMMUNICATION BETWEEN A CAPACITIVE TOUCH SCREEN AND AN ACTIVE STYLUS
    5.
    发明申请
    SYSTEM AND METHOD OF COMMUNICATION BETWEEN A CAPACITIVE TOUCH SCREEN AND AN ACTIVE STYLUS 有权
    电容触摸屏和活动板之间的通信系统和方法

    公开(公告)号:US20160048234A1

    公开(公告)日:2016-02-18

    申请号:US14461977

    申请日:2014-08-18

    IPC分类号: G06F3/044 G06F3/0354

    摘要: An active stylus is capacitively coupled to a capacitive touch panel for communication. The active stylus operates in a wait mode to receive initial communications from the panel. In response to such receipt, the active stylus synchronizes to a repeating communications frame implementing time division multiplexing. Communications from the active stylus to the panel include: information communications; synchronization communications and communications specific for columns and/or rows of the panel. Communications from the panel to the active stylus may be addressed uniquely to the stylus or commonly to a group of styluses.

    摘要翻译: 有源触笔电容耦合到用于通信的电容式触摸面板。 活动的笔在等待模式下操作以从面板接收初始通信。 响应于这样的接收,活动触针与实现时分复用的重复通信帧同步。 从活动手写笔到面板的通信包括:信息通信; 专用于面板的列和/或行的同步通信和通信。 从面板到活动手写笔的通信可以唯一地被寻址到手写笔,或者通常被发送到一组触控笔。

    HIGH SIGNAL TO NOISE RATIO CAPACITIVE SENSING ANALOG FRONT-END
    6.
    发明申请
    HIGH SIGNAL TO NOISE RATIO CAPACITIVE SENSING ANALOG FRONT-END 审中-公开
    高信号噪声比电容式传感模拟前端

    公开(公告)号:US20140077823A1

    公开(公告)日:2014-03-20

    申请号:US13717780

    申请日:2012-12-18

    IPC分类号: G01R27/26

    摘要: Capacitance sensing circuits and methods are provided. The capacitance sensing circuit includes a capacitance-to-voltage converter configured to receive a signal from a capacitance to be sensed and to provide an output signal representative of the capacitance, an output chopper configured to convert the output signal of the capacitance-to-voltage converter to a sensed voltage representative of the capacitance to be sensed, an analog accumulator configured to accumulate sensed voltages during an accumulation period of NA sensing cycles and to provide an accumulated analog value, an amplifier configured to amplify the accumulated analog value, and an analog-to-digital converter configured to convert the amplified accumulated analog value to a digital value representative of the capacitance to be sensed. The analog accumulator may include a low pass filter having a frequency response to filter wideband noise.

    摘要翻译: 提供电容感测电路和方法。 电容感测电路包括:电容 - 电压转换器,被配置为从要感测的电容接收信号并提供表示电容的输出信号;输出斩波器,被配置为转换电容 - 电压的输出信号 转换器到感测的电压,代表要感测的电容;模拟累加器,被配置为在NA感测周期的累积周期期间累积感测电压并提供累加的模拟值,被配置为放大所累积的模拟值的放大器和模拟 配置为将放大的累积模拟值转换为表示要感测的电容的数字值。 模拟累加器可以包括具有对滤波器宽带噪声的频率响应的低通滤波器。

    Stylus sensing on touchscreens
    7.
    发明授权

    公开(公告)号:US11422663B1

    公开(公告)日:2022-08-23

    申请号:US17332357

    申请日:2021-05-27

    IPC分类号: G06F3/044 G06F3/041

    摘要: In an example, a method of sensing on a touchscreen including a plurality of touch sensors arranged in rows and columns on the touchscreen is described. The method includes detecting a passive touch on the touchscreen and a positon of an active stylus; determining a plurality of locations across the touchscreen corresponding to the passive touch and a positon of the active stylus, where each of the plurality of locations corresponds to a location of one of the plurality of touch sensors. The method includes transmitting a first uplink signal to a first group of the plurality of locations including a first fraction of the plurality of locations; and transmitting a second uplink signal to a second group of the plurality of locations including a second fraction of the plurality of locations, the first uplink signal being different from the second uplink signal.

    CAPACITIVE DISCHARGE CIRCUIT FOR TOUCH SENSITIVE SCREEN

    公开(公告)号:US20170344158A1

    公开(公告)日:2017-11-30

    申请号:US15679771

    申请日:2017-08-17

    IPC分类号: G06F3/044 G06F3/041

    摘要: A capacitive discharge circuit includes a line having a capacitance, a switched capacitor circuit including a capacitor, a switched circuit coupled to the line, and a voltage regulator coupled between the switched capacitor circuit and the switched circuit. A controller operates the switched capacitor circuit and switched circuit to in a first phase, charge the capacitor by coupling the capacitor between a common mode and a power supply, and in a second phase, discharge the capacitor by coupling the voltage regulator in series with the capacitor between the power supply node a ground. The controller is also configured to in a third phase, charge the capacitor by coupling the capacitor between the common mode and the power supply, and in a fourth phase, share charge between the line and the capacitor by coupling the voltage regulator and the capacitor in series between the line and the ground.

    CAPACITIVE TOUCH SCREEN WITH TIME OVERLAPPED CONCURRENT SCANNING OPERATION USING CODED DRIVE SIGNALS
    10.
    发明申请
    CAPACITIVE TOUCH SCREEN WITH TIME OVERLAPPED CONCURRENT SCANNING OPERATION USING CODED DRIVE SIGNALS 审中-公开
    使用编码驱动信号的时间叠加同时扫描操作的电容触摸屏

    公开(公告)号:US20160313823A1

    公开(公告)日:2016-10-27

    申请号:US14693211

    申请日:2015-04-22

    发明人: Kien Beng Tan

    IPC分类号: G06F3/044

    CPC分类号: G06F3/044 G06F3/0416

    摘要: A capacitive sensing system includes a capacitive sensing panel with drive lines and sense lines. Each drive line includes a drive circuit. A code generator operates to generate modulation codes. A drive controller generates drive signals wherein each drive signal is modulated by one of the modulation codes. The generated drive signals are applied to the drive lines through the drive circuits. The drive controller operates to simultaneously generate the drive signals for application to a corresponding group of drive lines during a drive period. Separate groups of drive lines are sequentially driven with the same drive signals during drive periods that only partially overlap.

    摘要翻译: 电容感测系统包括具有驱动线和感测线的电容式感测面板。 每个驱动线包括驱动电路。 码发生器用于产生调制码。 驱动器控制器产生驱动信号,其中每个驱动信号由调制码之一调制。 所产生的驱动信号通过驱动电路施加到驱动线。 驱动控制器操作以在驱动周期期间同时产生用于施加到相应组的驱动线的驱动信号。 在仅部分重叠的驱动周期期间,用相同的驱动信号依次驱动单独的驱动线组。