Qualcomm Incorporated

Efthymios Philip Papageorgiou

Hrishikesh Vijaykumar Panchawagh

Yue Lu

Jessica Liu Strohmann

Ara Bicakci

Jae Hyeong Seo

Sean Joel Lyn

Ngar Loong Alan Chan

An apparatus for common mode noise cancellation in an ultrasonic fingerprint sensor comprising a resistor-inductor-capacitor (RLC) network, a piezoelectric layer, a pixel array electrically coupled with the RLC network at a first end of the RLC network and either: (A) a common mode canceling capacitive element electrically coupled with the RLC network in parallel with the pixel array and configured to attenuate at least a portion of the common mode component from the acoustic signal before the acoustic signal is received by the pixel array or (B) a common mode canceling circuitry electrically coupled with the RLC network at a second end of the RLC network and configured to introduce a feedback signal to the pixel array through the RLC network, wherein the feedback signal is determined based on the received acoustic signal at each pixel within the pixel array.

Ultrasonic fingerprint sensor with passive and active common mode cancellation

A modulator may include a controller configured to receive in-phase (I) baseband signals and quadrature-phase (Q) baseband signals. The controller may be configured to select a section of a region defined by a number of local oscillator (LO) phases. The controller may be configured to output multiple control signals and a pair of phase selection signals. The modulator may further include multiple output stages. Each output stage may be coupled to the controller to receive a pair of the control signals, the pair of phase selection signals, and multiple offset LO signals. Each of the output stages may include a unit element.

Modulator

Growing community of inventors

Berkeley, CA, United States of America

Efthymios Philip Papageorgiou