Touch input method and handheld apparatus using the method

A handheld apparatus with touch input function, comprising:

• a casing comprising a sidewall;
• a cover connected to the sidewall, an accommodation space being defined by the cover and the casing;
• a control circuit chip disposed in the accommodation space and operating in a first mode and a second mode;
• and
• a touch-sensitive module disposed in the accommodation space and electrically connected to the control circuit chip, the touch-sensitive module comprising:
• a first touch sensor set;
• and
• a second touch sensor set close to the sidewall, the second touch sensor set comprising a plurality of separate sensor pads arranged in a column, each separate sensor pad being connected to the control circuit chip through a respective trace,
• wherein, in the first mode, at least one of the separate sensor pads senses a first capacitance change thereof in response to an object in proximity of or in contact with the sidewall,
• wherein, in the second mode, the control circuit chip controls the separate sensor pads to be connected in parallel to form at least one sensor electrode, and the at least one sensor electrode cooperates with the first touch sensor set to sense a second capacitance change thereof in response to the object in proximity of or in contact with the cover.