Patent ID: 8319505
Filing Date: 2012-11-27
Classification: G01R,H03K,H03M

Abstract:
1. A capacitive measurement circuit, comprising: a first electrode capacitively coupled with a second electrode; a first plurality of switches coupled with the first electrode; and a second plurality of switches coupled with the second electrode, wherein, during a first operation stage, the first plurality of switches is configured to apply a first initial voltage to the first electrode and the second plurality of switches is configured to apply a second initial voltage to the second electrode, and wherein, during a second operation stage, the first plurality of switches is configured to connect the first electrode with a measurement circuit, and the second plurality of switches is configured to connect the second electrode with a constant voltage, wherein the measurement circuit is configured to generate an output signal based on a current generated by operation of the first plurality of switches, the circuit generating the output signal including a current mirror with a first end and a second end, the first end coupled to the first plurality of switches.