公开(公告)号：US12253401B2

公开(公告)日：2025-03-18

申请号：US17707688

申请日：2022-03-29

Applicant: InvenSense, Inc.

Inventor： Cristabel Yang ,  Richard J. Przybyla ,  Mitchell Kline

IPC: G01F23/2962 ,  G01F23/20 ,  G01F23/296 ,  G01F25/20

Abstract: Systems and methods for ultrasonic liquid level sensing. A circuit causes an ultrasonic transducer to transmit a sequence of ultrasonic pulses and receive a sequence of reflected signals. Each reflected signal includes at least one first reflection associated with at least one non-moveable surface and at least one second reflection associated with a moveable surface. A digital controller, for each reflected signal: determines at least one of a magnitude and a variance of the respective signal to form at least one output signal, identifies, in the at least one output signal, at least one first pulse indicative of the at least one non-moveable surface and at least one second pulse indicative of the moveable surface, and determines a distance of the moveable surface relative to the at least one non-moveable surface based on the identified first and second pulses.