| 摘要 |
A driving frequency selection method is used in a capacitive multi-touch system. When the system operates in an idle mode, an active driving frequency is selected randomly from N candidates, and a self-capacitance driving and sensing is used to detect touch points. When there are touch points, the capacitive multi-touch system is switched to an active mode to acquire an image raw data for finding the positions of touch points. In the active mode, noise is calculated from the image raw data. When the noise exceeds a predetermined value, the system is switched back to the idle mode, and the self-capacitance driving and sensing is applied to N-1 active driving frequencies other than the previously selected active driving frequency to acquire N-1 self-capacitance image raw data. The method determines one with a minimum noise and selects the corresponding frequency as a currently active driving frequency.
|
