| 摘要 |
A touch sensing device includes a touch surface circuit that facilitates a change in a coupling capacitance in response to a capacitance change touch occurring at the touch surface. The device includes a sensing circuit that provides a signal, in response to the capacitance change touch, having transient portions for indicating features of positive-going transitions towards an upper signal level and negative-going transitions towards a lower signal level. An amplification circuit is then used for amplifying and processing the signals, in response to time-varying input parameters. The amplification circuit adjusts the gain for the transient portions relative to a gain for portions of the response signals between the transient portions and suppresses RF interference, such as in the form of an odd and/or even-numbered harmonic signal so as to provide a noise filtered output for determining the position of the capacitance change touch on the touch surface. |
