The invention discloses a radio-frequency micro-
capacitance fingerprint acquisition
chip and method. The
chip comprises a plurality of reference sensing units, a two-dimensional sensing unit array formed by the reference sensing units, an insulating layer, an insulating substrate serving as a finger contact surface, a radio-frequency
signal generation circuit, a radio-frequency drive
electrode, a sensing unit array controller used for providing bias-power-supply switching signals for switching on or switching off the sensing units and charge-
discharge sequence signals needed by the sensing units, an analog-
digital conversion array, a digital-analog converter for controlling the
gain of the analog-
digital conversion array, a sensing unit offset correction circuit, a
fingerprint image cache, a
fingerprint image output controller and an
image signal processor. Due to the improvement of the structure of the sensing units and the additional arrangement of the sensing unit offset correction circuit, the radio-frequency micro-
capacitance fingerprint acquisition
chip can solve the problems of fingerprint residual, interference caused by other
radiofrequency radiation, false fingers and small detection depth; besides, the chip can be embedded into a capacitive touch screen.