公开(公告)号：US11675459B1

公开(公告)日：2023-06-13

申请号：US17934126

申请日：2022-09-21

Applicant: Apple Inc.

Inventor： Chang Yong Kang ,  Du Chen ,  Christoph H. Krah

IPC: G06F3/041 ,  G06F3/044 ,  G06F1/3234 ,  G06F1/3296

CPC classification number: G06F3/04184 ,  G06F1/3262 ,  G06F1/3296 ,  G06F3/0443 ,  G06F3/0446 ,  G06F3/044 ,  G06F2203/04107

Abstract: An electronic device can be configured to operate in a plurality of operating modes to generate various stimulation signals for touch sensing operations. Switching circuitry can selectively couple one or more stimulation circuits to touch stimulation circuitry to reduce electromagnetic interference generated during transitions between the plurality of operating modes. The electronic device can transition from a stimulation phase to a termination phase at an arbitrary time, unconstrained by integration time requirements of accompany touch sensing circuitry.

公开(公告)号：US11199933B2

公开(公告)日：2021-12-14

申请号：US17080723

申请日：2020-10-26

Applicant: Apple Inc.

Inventor： Christoph H. Krah ,  Du Chen

IPC: G06F3/044 ,  G06F3/041 ,  G02F1/1333

Abstract: Some touch screens can be formed by at least partially integrating touch sensing circuitry into a display pixel stackup. In some examples, noise can be introduced into touch sensor panel measurements, for example, from display data lines of a display device proximate to the touch sensor panel. In some examples, rows or columns of touch electrodes can be split and a first portion of the touch sensor panel can be stimulated to measure capacitance and noise and a second portion of the touch sensor panel can be unstimulated and measure noise. In some examples, both the first and the second portions of the touch sensor panel can be stimulated using orthogonal stimulation codes. In some examples, measurements from the first and/or second portions of the touch sensor panel can be subtracted from measurements from the other portion of the touch sensor panel to eliminate or reduce common mode noise.

公开(公告)号：US11880533B1

公开(公告)日：2024-01-23

申请号：US17934176

申请日：2022-09-21

Applicant: Apple Inc.

Inventor： Du Chen ,  Christoph H. Krah

IPC: H02M3/158 ,  G06F3/041 ,  G06F1/08 ,  G06F3/044

CPC classification number: G06F3/0418 ,  G06F1/08 ,  G06F3/0412 ,  G06F3/0416 ,  H02M3/158 ,  G06F3/044 ,  G06F2203/04107

Abstract: A power management circuit can comprise a direct-current-to-direct-current (DC-DC) converter and a guard buffer. The guard buffer can be referenced to a system ground and configured to generate a guard ground. The power management circuit can comprise a supply capacitor coupled to the DC-DC converter that can be referenced to system ground in a first mode and referenced to the guard ground in a second mode. A regulator can be coupled to the DC-DC converter and referred to system ground in the first mode, and decoupled and referred to guard ground in the second mode. The DC-DC converter can generate a first voltage in the first mode and a second voltage in the second mode, the second voltage greater than the first.

公开(公告)号：US12013741B2

公开(公告)日：2024-06-18

申请号：US18317894

申请日：2023-05-15

Applicant: Apple Inc.

Inventor： Du Chen ,  Christoph H. Krah

IPC: G06F1/3234 ,  G06F1/3296 ,  G06F3/041 ,  G06F3/044

CPC classification number: G06F1/3262 ,  G06F1/3296 ,  G06F3/0412 ,  G06F3/04184 ,  G06F3/0443 ,  G06F3/0446 ,  G06F3/044 ,  G06F2203/04107

Abstract: An electronic device can be configured to operate in a plurality of operating modes to generate various stimulation signals for touch sensing operations. Switching circuitry can selectively couple one or more stimulation circuits to touch stimulation circuitry to reduce electromagnetic interference generated during transitions between the plurality of operating modes. The electronic device can transition from a stimulation phase to a termination phase at an arbitrary time, unconstrained by integration time requirements of accompany touch sensing circuitry.