公开(公告)号：US09921668B1

公开(公告)日：2018-03-20

申请号：US13749829

申请日：2013-01-25

Applicant: Qualcomm Technologies, Inc.

Inventor： Trishabh Chadda ,  Guozhong Shen ,  Jon Pearson

IPC: G06F3/041

CPC classification number: G06F3/041 ,  G06F3/0418 ,  G06F3/044

Abstract: A touch panel controller is disclosed herein. The controller includes output circuitry for driving a touch panel sensor and input circuitry for determining when an object performs a touch event over the touch panel sensor. The controller is configured to cause the output circuitry to generate drive signals having a different frequency characteristic when the controller determines noise present within the sensor is above a noise threshold. The controller communicates with a software device driver on a host processor to store signal baseline images for a range of frequencies during production test and power-up. The controller is configured to receive a signal baseline image from the host processor when the controller causes change to a different drive frequency. The controller is configured to cause change to the different drive frequency while the object is still performing the touch event over the touch panel sensor.