Patent ID: 11940530
Assignee: SHANGHAI TIANMA MICRO-ELECTRONICS CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC G  H  Y | IPC G  H

Claim 17:
18. A driving method of an ultrasonic fingerprint identification circuit, the driving method being used to drive the ultrasonic fingerprint identification circuit according to claim 1, wherein a driving cycle of each of the plurality of fingerprint identification units of the ultrasonic fingerprint identification circuit comprises a preparation period, a pull-up period, and a reading period, and
wherein the driving method comprises:
in the preparation period, converting, by the ultrasonic fingerprint identification sensor, the first electrical signal to the ultrasonic signal and radiating the ultrasonic signal towards the finger, providing, by the one first control signal line of a plurality of first control signal lines, the first level, and transmitting, by the control circuit, the second level provided by the composite signal line to the first node;
in the pull-up period, converting, by the ultrasonic fingerprint identification sensor, the ultrasonic signal reflected by the finger to the second electrical signal and transmitting the second electrical signal to the first node, providing, by the composite signal line, the first level, and transmitting, by the control circuit, the first level provided by the composite signal line to the first node, to pull up the potential of the first node; and
in the reading period, providing, by one of the plurality of second control signal lines, the first level, and reading, by the reading circuit, the detection signal of the first node.