| 摘要 |
The present invention provides a fingerprint detection circuit, a sensor, and a touch screen. The fingerprint detection circuit includes: a detection electrode, where a first capacitance is formed between a finger and the detection electrode, a second capacitance is formed between the finger and a virtual ground, and a parasitic capacitance is formed between the detection electrode and the virtual ground; an amplifier, where an inverting input end of the amplifier is connected to the detection electrode and a non-inverting input end of the amplifier is connected to an excitation signal; and a feedback capacitance, where one end of the feedback capacitance is connected to the inverting input end of the amplifier, the other end of the feedback capacitance is connected to an output end of the amplifier, and the output end of the amplifier outputs an output signal of the fingerprint detection circuit. According to the fingerprint detection circuit in the embodiments of the present invention, all signals of the circuit are in a detection chip and there is no need to connect an excitation signal to a finger of a user through an external electrode, making fingerprint detection applicable to more scenarios. For example, a detection electrode arranged in an array may be placed under the screen glass of a mobile terminal. |
