Capacitance sensing circuit for sensing capacitance change by utilizing charge replication method

The invention provides a capacitance sensing circuit for sensing capacitance change by utilizing a charge replication method, which comprises at least one capacitor to be detected, an integrating capacitor and a first current mirror with a first current path and a second current path, and the capacitors to be detected can be touched to generate capacitance change. When connected with a circuit between the capacitors to be detected, the first current path generates first current to charge the capacitors to be detected, and meanwhile, the second current path generates second current mapped to the first current to charge the integrating capacitor; consequently, by mapping the charging current on the capacitors to be detected in order to utilize the mapped current to charge the integrating capacitor, the charge energy charged in the capacitors to be detected can be replicated in the integrating capacitor to reflect a voltage signal, and afterward, the capacitance change which is generated when the capacitors to be detected are touched is sensed by detecting the voltage signal.