Capacitor i.e. floating capacitor, characterizing/measuring method for controlling capacitive touch screen display, involves measuring time needed for voltage of midpoint of bridge to become equal to voltage of midpoint of another bridge

摘要

The method involves connecting a capacitor (Cc) to a midpoint (N1) of a capacitive voltage-dividing bridge (L1), and applying a bias voltage (V3) to the dividing bridge and another capacitive voltage-dividing bridge (L2) that is in parallel with the former bridge. Voltage (V1) of the midpoint is kept near a reference voltage (Vref). Another midpoint (N2) of the latter bridge is released by a constant current (I). Time needed for a voltage (V2) of the latter midpoint to become equal to the voltage of the former midpoint is measured. An independent claim is also included for a device for characterizing or measuring a capacitor, comprising a capacitive voltage-dividing bridge.