SLOPE WAVE GENERATION CIRCUIT AND DIGITAL-TO-ANALOG CONVERSION CIRCUIT THEREOF, FINGERPRINT IDENTIFICATION SYSTEM

摘要

The present invention, related to the technical field of fingerprint identification, discloses a ramp wave generation circuit, a digital-to-analog conversion circuit, and a fingerprint identification system. The ramp wave generation circuit comprises: an integrating circuit, configured to output a ramp wave signal; a signal regulation circuit, comprising a feedback control loop and a transconductance amplifier connected in series, wherein the feedback control loop monitors the ramp wave signal output by the integrating circuit, and outputs a regulation control signal to the transconductance amplifier, the transconductance amplifier corrects, according to the regulation control signal, a ramp wave signal output by the integrating circuit within a next period; and a voltage generation circuit, configured to respectively output a reference voltage signal to the integrating circuit and the signal regulation circuit. With the fingerprint identification system, the problem that a ramp wave generation circuit and a clock generator cause deterioration of the performance of a fingerprint system due to impacts of PVT in the related art may be solved.