Patents by Inventor Yat Tung Lai

Yat Tung Lai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11929770
    Abstract: An On-Off Shift Keying (OOK) receiver has non-continuous Automatic Gain Control (AGC) that sets gain at the beginning of each frame and locks the gain setting for the remainder of the frame, preventing OOK data from causing AGC loop instability. An AGC controller initializes to maximum the gain settings for a Low-Noise Amplifier (LNA), Low-Pass Filter (LPF), and a Programmable Gain Amplifier (PGA) in series that power a rectifier generating a voltage output to a 1/0 data decision circuit. A level detector compares the voltage output to two thresholds. When both thresholds are exceeded, the AGC controller steps down gain settings until the voltage output is between the two thresholds, when the gain settings are locked for the remainder of the current frame. A frame detector resets the AGC controller between frames when a long series of 0 data between frames is detected. LNA gain is reduced last.
    Type: Grant
    Filed: March 6, 2023
    Date of Patent: March 12, 2024
    Assignee: Hong Kong Applied Science and Technology Research Institute Company Limited
    Inventors: Yat Tung Lai, Lu Chen, Wuxue Ni, Huimin Guo
  • Patent number: 11650656
    Abstract: A voltage detector has a diode ladder with one or more diodes connected in series between a battery voltage input and an upper measuring node. A measuring diode is connected between the upper measuring node and a lower measuring node. A resistor and a power-down switch are connected in series between the lower measuring node and a ground. An analog input to an Analog-to-Digital Converter (ADC) is connected by a switch to the upper measuring node to generate an upper digital value. Then the switch connects the analog input to the lower measuring node to generate a lower digital value. The difference between the upper and lower digital values is the diode voltage drop across the measuring diode and is multiplied by a number of diodes in the diode ladder and added to the upper digital value to generate a battery voltage measurement.
    Type: Grant
    Filed: April 20, 2022
    Date of Patent: May 16, 2023
    Inventors: Wai Po Wong, Huimin Guo, Yat Tung Lai
  • Patent number: 11171675
    Abstract: A switch-less transceiver has parallel LC resonances that act as OFF switches and series LC resonances act as ON switches when resonating at the transmit (TX) or receive (RX) frequency. When the transmitter is disabled, no current flows through series LC filters. Instead, series impedances to ground provide an RF ground to the transmitter output node. A TX inductor between the transmitter output node and the antenna is in parallel with a TX blocking capacitor to ground, which together form a parallel resonance to ground that has a high impedance when resonating at the receiver frequency. This high impedance acts as an OFF switch to block antenna signals from entering the transmitter. The two paths are in parallel, presenting a high impedance to the antenna and forming an OFF switch when the receiver is disabled.
    Type: Grant
    Filed: March 17, 2021
    Date of Patent: November 9, 2021
    Assignee: Hong Kong Applied Science and Technology Research Institute Company, Limited
    Inventors: Huimin Guo, Yujian Han, Yat Tung Lai
  • Patent number: 10483948
    Abstract: A RC oscillator comprises a resistor unit. The resistor unit can comprise at least one set of compensation resistor. Each set of compensation resistor comprises a positive temperature coefficient resistor and a negative temperature coefficient resistor coupled in series with the positive temperature coefficient resistor.
    Type: Grant
    Filed: November 3, 2017
    Date of Patent: November 19, 2019
    Assignee: Johnson Electric International AG
    Inventors: Chiping Sun, Ken Wong, Huimin Guo, Yat Tung Lai, Shujuan Huang
  • Patent number: 10305425
    Abstract: An RC oscillator has a variable capacitor that sets the output frequency. The variable capacitor has m binary-weighted switched capacitor arrays, and each binary-weighted switched capacitor array has binary-weighted capacitors. p binary bits are decoded into an m-bit thermometer code that selects one of the m binary-weighted switched capacitor arrays to use n binary bits to switch its binary-weighted capacitors. Other binary-weighted switched capacitor arrays have all their capacitors switched on, or all their capacitors switched off by the thermometer code. The smallest or unit capacitance of each binary-weighted switched capacitor array is adjusted to compensate for the non-linear reciprocal relationship of frequency being proportional to 1/RC. The unit capacitance is increased for each successive binary-weighted switched capacitor array to reset to the ideal linear relationship of the (p,n)-bit code to frequency.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: May 28, 2019
    Assignee: Hong Kong Applied Science and Technology Research Institute Company, Limited
    Inventors: Huimin Guo, Zhongliang Zhou, Yat Tung Lai
  • Publication number: 20190131929
    Abstract: An RC oscillator has a variable capacitor that sets the output frequency. The variable capacitor has m binary-weighted switched capacitor arrays, and each binary-weighted switched capacitor array has binary-weighted capacitors. p binary bits are decoded into an m-bit thermometer code that selects one of the m binary-weighted switched capacitor arrays to use n binary bits to switch its binary-weighted capacitors. Other binary-weighted switched capacitor arrays have all their capacitors switched on, or all their capacitors switched off by the thermometer code. The smallest or unit capacitance of each binary-weighted switched capacitor array is adjusted to compensate for the non-linear reciprocal relationship of frequency being proportional to 1/RC. The unit capacitance is increased for each successive binary-weighted switched capacitor array to reset to the ideal linear relationship of the (p,n)-bit code to frequency.
    Type: Application
    Filed: October 30, 2017
    Publication date: May 2, 2019
    Inventors: Huimin GUO, Zhongliang ZHOU, Yat Tung LAI
  • Publication number: 20180131299
    Abstract: A RC oscillator comprises a resistor unit. The resistor unit can comprise at least one set of compensation resistor. Each set of compensation resistor comprises a positive temperature coefficient resistor and a negative temperature coefficient resistor coupled in series with the positive temperature coefficient resistor.
    Type: Application
    Filed: November 3, 2017
    Publication date: May 10, 2018
    Inventors: Chiping SUN, Ken WONG, Huimin GUO, Yat Tung LAI, Shujuan HUANG
  • Publication number: 20180131295
    Abstract: A motor-driven integrated circuit can include a bare die having an 8-bit microcontroller. The 8-bit microcontroller is fabricated by a 0.15 ?m semiconductor process.
    Type: Application
    Filed: November 3, 2017
    Publication date: May 10, 2018
    Inventors: Chiping SUN, Ken WONG, Huimin GUO, Yat Tung LAI, Yunlong JIANG
  • Patent number: 9385625
    Abstract: A RF-to-DC converter charges a battery or powers a circuit from the energy of received radio waves. The RF energy received is very small for far-field applications, so the converter is highly sensitive. Four capacitor arrays are arranged in two banks. Buffered RF signals pump bottom plates of the capacitors. A series of L-switches in each bank connect between the two capacitor arrays in that bank. Each L switch has a pre-charge switch that charges that stage's input capacitor, and a stage-transfer switch that shares charge from the input capacitor to an output capacitor for that stage. Switches in the two banks alternately pre-charge and pump, with the left bank pumping while the right bank pre-charges. Switches are transistors with substrates tied to their sources or actively driven by substrate control signals. One bank may use n-channel transistors with the other bank uses p-channel transistors. Gate voltages may be boosted.
    Type: Grant
    Filed: April 15, 2015
    Date of Patent: July 5, 2016
    Assignee: Hong Kong Applied Science and Technology Research Institute Company, Limited
    Inventors: Kwok Kuen (David) Kwong, Yat Tung Lai, Ka Hung Kwok
  • Patent number: 8258852
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: September 4, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi David Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen David Kwong
  • Publication number: 20120126736
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 24, 2012
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen KWONG
  • Patent number: 8179455
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: May 15, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi (David) Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen (David) Kwong
  • Publication number: 20110221938
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Application
    Filed: March 11, 2010
    Publication date: September 15, 2011
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen (David) KWONG