公开(公告)号：US09703433B2

公开(公告)日：2017-07-11

申请号：US14461977

申请日：2014-08-18

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Praveesh Chandran ,  Baranidharan Karuppusamy ,  Giuseppe Noviello ,  Chee Weng Cheong ,  Leonard Dinu ,  Dianbo Guo ,  Kien Beng Tan ,  Chaochao Zhang

IPC: G06F3/045 ,  G06F3/044 ,  G06F3/0354 ,  G06F3/038 ,  G06F3/041

CPC classification number: G06F3/044 ,  G06F3/03545 ,  G06F3/0383 ,  G06F3/0416

Abstract: An active stylus is capacitively coupled to a capacitive touch panel for communication. The active stylus operates in a wait mode to receive initial communications from the panel. In response to such receipt, the active stylus synchronizes to a repeating communications frame implementing time division multiplexing. Communications from the active stylus to the panel include: information communications; synchronization communications and communications specific for columns and/or rows of the panel. Communications from the panel to the active stylus may be addressed uniquely to the stylus or commonly to a group of styluses.

公开(公告)号：US12149094B2

公开(公告)日：2024-11-19

申请号：US17490437

申请日：2021-09-30

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Chee Weng Cheong ,  Kien Beng Tan

IPC: H02J3/32 ,  G01R19/165 ,  H02J7/04 ,  H02J50/10 ,  H02J50/90 ,  H02M1/00 ,  H02M3/156 ,  H02M7/217 ,  H02M7/219 ,  H03K17/687

Abstract: A wireless power receiver includes a rectifier with first and second inputs coupled to first and second terminals of a receiver coil, and having a first output coupled to ground and a second output at which a rectified voltage is produced. A first switch is coupled between the second input and ground, and is controlled by a first gate voltage generated at a first node. A second switch is coupled between the first node and ground, and is controlled by a second gate voltage. The first gate voltage closes the first switch to couple the second input to ground when the rectified voltage is less than a threshold voltage, boosting the rectified voltage. The second gate voltage closes the second switch to cause the second gate voltage to be pulled to ground when the rectified voltage is greater than the threshold voltage, limiting the boosting of the rectified voltage.

公开(公告)号：US11387676B2

公开(公告)日：2022-07-12

申请号：US17007225

申请日：2020-08-31

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Eng Jye Ng ,  Chee Weng Cheong ,  Huiqiao He

IPC: H02J50/10 ,  H02M1/36 ,  H02M1/00 ,  H02J7/02 ,  H02M1/08

Abstract: A system comprising includes a wireless power receiver generating a rectified voltage. A low dropout regulator (LDO) generates a first regulated output voltage from the rectified voltage, during a first phase. A first switch couples the first regulated output voltage to a voltage output node during the first phase. During a second phase, the LDO generates a second regulated output voltage from the rectified voltage. A switching regulator generates a third regulated output voltage during the second phase. A second switch couples the third regulated output voltage to the voltage output node during the second phase. During a third phase, the LDO is disabled, while the switching regulator continues to generate the third regulated output voltage. The first switch opens during the third phase while the second switch remains closed.

公开(公告)号：US11165286B1

公开(公告)日：2021-11-02

申请号：US16899990

申请日：2020-06-12

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Teerasak Lee ,  Chee Weng Cheong ,  Yannick Guedon ,  Eng Jye Ng

IPC: H01F27/42 ,  H01F37/00 ,  H01F38/00 ,  H02J50/80 ,  H03F1/02 ,  H02J50/10 ,  H02J50/00

Abstract: A data demodulating circuit includes a sensing circuit sensing a power signal applied to a coil at first and second times, and outputting an analog value representing a difference in voltage of the power signal at the first and second times. An analog-to-digital converter digitizes the analog value output by the analog voltage differential sensing circuit to produce a digital code. A compensation circuit, over a period of time, compares a present value of the digital code to a first value of the digital code during the period, and subtracts a given value from the present value of the digital code if the present value is greater than the first value but add the given value to the present value of the digital code if the present value is less than the first value. An accumulator accumulates output of the compensation circuit, and a filter filters output of the accumulator.

公开(公告)号：US09990091B2

公开(公告)日：2018-06-05

申请号：US14753129

申请日：2015-06-29

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Chee Weng Cheong ,  EngJye Ng ,  Dianbo Guo ,  Chaochao Zhang ,  Kusuma Adi Ningrat

IPC: G06F3/045 ,  G06F3/044

CPC classification number: G06F3/044

Abstract: A charge sensing circuit generates a voltage in a sensing period that is indicative of sensed charge. The generated voltages are accumulated by an accumulator circuit over a number of sensing periods. A noise detection circuit senses when the voltage generated by the charge sensing circuit is outside of a boundary and generates a detection signal in response thereto. A control circuit, in response to the detection signal, controls the accumulator circuit to block accumulation of the voltages generated by the charge sensing circuit during at least the sensing period in which the detection signal is generated. An analog-to-digital converter circuit then converts an accumulated output voltage from the accumulator circuit to a digital value at the end of an accumulation time period that includes the sensing periods. The end of the accumulation time period is delayed by at least one sensing period in response to the detection signal.

公开(公告)号：US20180046320A1

公开(公告)日：2018-02-15

申请号：US15235974

申请日：2016-08-12

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Hugo Gicquel ,  Chee Weng Cheong

IPC: G06F3/041 ,  G06F3/044

CPC classification number: G06F3/0418 ,  G06F3/044 ,  G06F2203/04108

Abstract: A circuit described herein includes a charge to voltage converter circuit having an input coupled to receive a sense signal from a sense node associated with a mutual capacitance to be sensed, and an output. A reset switch is coupled between the output of the charge to voltage converter circuit and the input of the charge to voltage converter. An accumulator circuit is configured to accumulate voltages at the output of the charge to voltage converter circuit and to generate an accumulator output signal. Control circuitry is configured to generate control signals for the reset switch and accumulator circuit so as to reduce noise in the accumulator output signal.

公开(公告)号：US09772696B2

公开(公告)日：2017-09-26

申请号：US14199510

申请日：2014-03-06

Applicant: STMICROELECTRONICS ASIA PACIFIC PTE LTD

Inventor： Leonard Liviu Dinu ,  Chee Weng Cheong

IPC: H04L7/00 ,  H04L25/00 ,  H04L25/40 ,  G06F3/0354 ,  G06F3/041 ,  H03L7/00

CPC classification number: G06F3/03545 ,  G06F3/041 ,  G06F3/0416 ,  G06F3/044 ,  G06F2203/0384 ,  H03L7/00

Abstract: A system and method for compensating for detected phase errors during communications between synchronized devices. In an embodiment, the two devices may be a touch screen device and a synchronized stylus device. To this end, the touch screen device includes a controller configured to receive data signals from the stylus at specific time intervals. The touch screen device generates an internal control signal for receiving the incoming data signals at an expected frequency. The touch screen device further includes circuitry for measuring differences in the time a data signal is actually received against when the data signal was expected to be received and determines a time difference (e.g., a phase error). Then, the internal control signal may be adjusted to compensate for the accumulated phase error. Such a measurement and compensation helps ensure that communications remain in synchronization without having to reestablish synchronization through a cumbersome synchronization process.

公开(公告)号：US20170269740A1

公开(公告)日：2017-09-21

申请号：US15616294

申请日：2017-06-07

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Praveesh Chandran ,  Baranidharan Karuppusamy ,  Giuseppe Noviello ,  Chee Weng Cheong ,  Leonard Dinu ,  Dianbo Guo ,  Kien Beng Tan ,  Chaochao Zhang

IPC: G06F3/044 ,  G06F3/038 ,  G06F3/0354 ,  G06F3/041

CPC classification number: G06F3/044 ,  G06F3/03545 ,  G06F3/0383 ,  G06F3/0416

Abstract: An active stylus is capacitively coupled to a capacitive touch panel for communication. The active stylus operates in a wait mode to receive initial communications from the panel. In response to such receipt, the active stylus synchronizes to a repeating communications frame implementing time division multiplexing. Communications from the active stylus to the panel include: information communications; synchronization communications and communications specific for columns and/or rows of the panel. Communications from the panel to the active stylus may be addressed uniquely to the stylus or commonly to a group of styluses.

公开(公告)号：US20160048234A1

公开(公告)日：2016-02-18

申请号：US14461977

申请日：2014-08-18

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Praveesh Chandran ,  Baranidharan Karuppusamy ,  Giuseppe Noviello ,  Chee Weng Cheong ,  Leonard Dinu ,  Dianbo Guo ,  Kien Beng Tan ,  Chaochao Zhang

IPC: G06F3/044 ,  G06F3/0354

CPC classification number: G06F3/044 ,  G06F3/03545 ,  G06F3/0383 ,  G06F3/0416

Abstract: An active stylus is capacitively coupled to a capacitive touch panel for communication. The active stylus operates in a wait mode to receive initial communications from the panel. In response to such receipt, the active stylus synchronizes to a repeating communications frame implementing time division multiplexing. Communications from the active stylus to the panel include: information communications; synchronization communications and communications specific for columns and/or rows of the panel. Communications from the panel to the active stylus may be addressed uniquely to the stylus or commonly to a group of styluses.

Abstract translation: 有源触笔电容耦合到用于通信的电容式触摸面板。 活动的笔在等待模式下操作以从面板接收初始通信。 响应于这样的接收，活动触针与实现时分复用的重复通信帧同步。 从活动手写笔到面板的通信包括：信息通信; 专用于面板的列和/或行的同步通信和通信。 从面板到活动手写笔的通信可以唯一地被寻址到手写笔，或者通常被发送到一组触控笔。

公开(公告)号：US10394349B2

公开(公告)日：2019-08-27

申请号：US15953017

申请日：2018-04-13

Applicant: STMicroelectronics Asia Pacific Pte Ltd

Inventor： Chee Weng Cheong ,  Leonard Liviu Dinu ,  Dianbo Guo ,  Kien Beng Tan

IPC: G06F3/038 ,  G06F3/041 ,  H04L27/00 ,  G06F3/0354

Abstract: A system and method for synchronizing two devices in communication with each other. When communication between the two devices is to be established, a synchronization process may be invoked. In an embodiment, a first device may initiate sending synchronization signals having rising edge and falling edge pairs. The second device may include a controller configured to receive the synchronization signals. However, noise may inhibit the ability of the controller to correctly receive and/or interpret the synchronization signals. Noise may cause detection components to falsely detect noise as a synchronization signal or may cause detection components to miss detection of an actual synchronization signal. A window generator may be used to generate comparison windows for the controller to detect synchronization signals. Further, the detection window duration and start times may be adjusted based on previously detected (or undetected) synchronization signals in order to compensate for noise overshadowing synchronization signals.