Patents by Inventor Ta-Chang Chen

Ta-Chang Chen 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: 12009753
    Abstract: A half-bridge flyback power converter: a first transistor, a second transistor and a third transistor which form a half-bridge circuit. The first transistor is turned on for generating a negative circulated current for achieving zero voltage switching of the second transistor. The second transistor is turned on for magnetizing a transformer. The third transistor is turned on during a demagnetized time period to generate an output voltage. The physical size of the first transistor is smaller than physical size of the third transistor.
    Type: Grant
    Filed: February 16, 2022
    Date of Patent: June 11, 2024
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung Yang, Ying-Chieh Su, Yu-Chang Chen
  • Publication number: 20240134268
    Abstract: A mask for use in a semiconductor lithography process includes a substrate, a mask pattern disposed on the substrate, and a light absorbing border surrounding the mask pattern. The light absorbing border is inset from at least two edges of the substrate to define a peripheral region outside of the light absorbing border. In some designs, a first peripheral region extends from an outer perimeter of the light absorbing border to a first edge of the substrate, and a second peripheral region that extends from the outer perimeter of the light absorbing border to a second edge of the substrate, where the first edge of the substrate and the second edge of the substrate are on opposite sides of the mask pattern.
    Type: Application
    Filed: January 3, 2024
    Publication date: April 25, 2024
    Inventors: Chien-Cheng Chen, Huan-Ling Lee, Ta-Cheng Lien, Chia-Jen Chen, Hsin-Chang Lee
  • Publication number: 20240128876
    Abstract: A switching control circuit for use in controlling a resonant flyback power converter generates a first driving signal and a second driving signal. The first driving signal is configured to turn on the first transistor to generate a first current to magnetize a transformer and charge a resonant capacitor. The transformer and charge a resonant capacitor are connected in series. The second driving signal is configured to turn on the second transistor to generate a second current to discharge the resonant capacitor. During a power-on period of the resonant flyback power converter, the second driving signal includes a plurality of short-pulses configured to turn on the second transistor for discharging the resonant capacitor. A pulse-width of the short-pulses of the second driving signal is short to an extent that the second current does not exceed a current limit threshold.
    Type: Application
    Filed: June 15, 2023
    Publication date: April 18, 2024
    Inventors: Yu-Chang Chen, Ta-Yung Yang, Kun-Yu Lin, Fu-Ciao Syu, Chia-Hsien Yang, Hsin-Yi Wu
  • Patent number: 11962247
    Abstract: A resonant half-bridge flyback power converter includes: a first transistor and a second transistor which form a half-bridge circuit; a transformer and a resonant capacitor connected in series and coupled to the half-bridge circuit; and a switching control circuit configured to generate a first driving signal and a second driving signal to control the first transistor and the second transistor respectively for switching the transformer to generate an output voltage. The first driving signal is configured to magnetize the transformer. The second driving signal includes at most one pulse between two consecutive pulses of the first driving signal. The switching control circuit generates a skipping cycle period when an output power is lower than a predetermined threshold. A resonant pulse of the second driving signal is skipped during the skipping cycle period. The skipping cycle period is increased in response to the decrease of the output power.
    Type: Grant
    Filed: February 16, 2022
    Date of Patent: April 16, 2024
    Assignee: RICHTEK TECHNOLOGY CORPORATION
    Inventors: Ta-Yung Yang, Ying-Chieh Su, Yu-Chang Chen
  • Publication number: 20240120844
    Abstract: A resonant flyback power converter includes: a first and a second transistors which form a half-bridge circuit for switching a transformer and a resonant capacitor to generate an output voltage; a current-sense device for sensing a switching current of the half-bridge circuit to generate a current-sense signal; and a switching control circuit generating a first and a second driving signals for controlling the first and the second transistors. The turn-on of the first driving signal controls the half-bridge circuit to generate a positive current to magnetize the transformer and charge the resonant capacitor. The turn-on of the second driving signal controls the half-bridge circuit to generate a negative current to discharge the resonant capacitor. The switching control circuit turns off the first transistor when the positive current exceeds a positive-over-current threshold, and/or, turns off the second transistor when the negative current exceeds a negative-over-current threshold.
    Type: Application
    Filed: April 10, 2023
    Publication date: April 11, 2024
    Inventors: Kun-Yu LIN, Ta-Yung YANG, Yu-Chang CHEN, Hsin-Yi WU, Fu-Ciao SYU, Chia-Hsien YANG
  • Publication number: 20240120845
    Abstract: A resonant flyback power converter includes: a first transistor and a second transistor which are configured to switch a transformer and a resonant capacitor for generating an output voltage; and a switching control circuit generating first and second driving signals for controlling the first and the second transistors. The turn-on of the first driving signal magnetizes the transformer. The second driving signal includes a resonant pulse having a resonant pulse width and a ZVS pulse during the DCM operation. The resonant pulse is configured to demagnetize the transformer. The resonant pulse has a first minimum resonant period for a first level of the output load and a second minimum resonant period for a second level of the output load. The first level is higher than the second level and the second minimum resonant period is shorter than the first minimum resonant period.
    Type: Application
    Filed: April 14, 2023
    Publication date: April 11, 2024
    Inventors: Yu-Chang Chen, Ta-Yung Yang, Kun-Yu Lin, Hsin-Yi Wu
  • Publication number: 20240120846
    Abstract: A resonant flyback power converter includes: a first transistor and a second transistor which are configured to switch a transformer and a resonant capacitor for generating an output voltage; and a switching control circuit generating first and second driving signals for controlling the first and the second transistors. The turn-on of the first driving signal magnetizes the transformer. During a DCM (discontinuous conduction mode) operation, the second driving signal includes a resonant pulse for demagnetizing the transformer and a ZVS (zero voltage switching) pulse for achieving ZVS of the first transistor. The resonant pulse is skipped when the output voltage is lower than a low-voltage threshold.
    Type: Application
    Filed: April 14, 2023
    Publication date: April 11, 2024
    Inventors: Yu-Chang Chen, Ta-Yung Yang, Kun-Yu Lin, Hsin-Yi Wu
  • Publication number: 20240077804
    Abstract: A method includes forming a test pattern and a reference pattern in an absorption layer of a photomask structure. The test pattern has a first trench and a second trench, the reference pattern has a third trench and a fourth trench, the test pattern and the reference pattern have substantially the same dimension in a top view, and the second trench is deeper than the first trench, the third trench, and the fourth trench. The method further includes emitting a light beam to the test pattern to obtain a first interference pattern reflected from the test pattern, emitting the light beam to the reference pattern to obtain a second interference pattern reflected from the reference pattern; and comparing the first interference pattern with the second interference pattern to obtain a measured complex refractive index of the absorption layer.
    Type: Application
    Filed: September 1, 2022
    Publication date: March 7, 2024
    Applicant: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Ping-Hsun LIN, Chien-Cheng CHEN, Shih Ju HUANG, Pei-Cheng HSU, Ta-Cheng LIEN, Hsin-Chang LEE
  • Publication number: 20240069431
    Abstract: In a method of manufacturing an attenuated phase shift mask, a photo resist pattern is formed over a mask blank. The mask blank includes a transparent substrate, an etch stop layer on the transparent substrate, a phase shift material layer on the etch stop layer, a hard mask layer on the phase shift material layer and an intermediate layer on the hard mask layer. The intermediate layer is patterned by using the photo resist pattern as an etching mask, the hard mask layer is patterned by using the patterned intermediate layer as an etching mask, and the phase shift material layer is patterned by using the patterned hard mask layer as an etching mask. The intermediate layer includes at least one of a transition metal, a transition metal alloy, or a silicon containing material, and the hard mask layer is made of a different material than the intermediate layer.
    Type: Application
    Filed: February 16, 2023
    Publication date: February 29, 2024
    Inventors: Wei-Che HSIEH, Chien-Cheng Chen, Ping-Hsun Lin, Ta-Cheng Lien, Hsin-Chang Lee
  • Publication number: 20120169604
    Abstract: A method for preventing mis-touch of a touch keyboard includes triggering a timer when the touch keyboard is touched. A key code corresponding to the touched position is obtained and stored in a storage unit. When the touched position discontinues being touched, the timer is stopped and a touched time of the touch keyboard is obtained from the timer. The touched time is compared with a touched-time upper bound. If the touched time is less than the touched-time upper bound, the stored key code is output.
    Type: Application
    Filed: December 29, 2011
    Publication date: July 5, 2012
    Inventors: Ta-Chang Chen, Mu-Te Chien, Chun-Yin Wu, Chen-Yi Wang, Chi-Hsin Lin, Shi-Kuan Chen
  • Publication number: 20120146912
    Abstract: A method for adjusting a display appearance of a keyboard layout displayed on a touch display unit includes the steps of: (A) detecting a first touch press at a start datum point of the touch display unit; (B) detecting a second touch press at a first position different from the start datum point; (C) detecting a motion track on the touch display unit; (D) computing a key pitch and a key size parameter of the keyboard layout, based on a relative position relationship between the start datum point and the first position; (E) computing a curvature and a curving mode of the keyboard layout, based on a shifting direction and a shifting distance of the motion track; and (F) adjusting a display appearance of the keyboard layout, based on the key pitch, the key size parameter, the curvature, and the curving mode.
    Type: Application
    Filed: March 23, 2011
    Publication date: June 14, 2012
    Applicant: Compal Electronics, INC.
    Inventors: Ta-Chang Chen, Shi Kuan Chen, Ming-Che Weng, Maohu Lai, Bo Chiang Wang
  • Publication number: 20100103348
    Abstract: A display including a display panel, a transparent rear plate, a backlight module, and a first optical film set is provided. The transparent rear plate has a first surface, a second surface, and an optical decoration. The first surface is facing the display panel, and the second surface is relatively far away from the display panel. The optical decoration is located on at least one of the first and second surfaces. The backlight module is disposed between the display panel and the transparent rear plate. The first optical film set is disposed between the backlight module and the transparent rear plate. Combination of the optical decoration, the backlight module, and the first optical film set forms a plurality of images which can be displayed on the second surface of the transparent rear plate.
    Type: Application
    Filed: May 5, 2009
    Publication date: April 29, 2010
    Applicant: COMPAL ELECTRONICS, INC.
    Inventor: Ta-Chang Chen
  • Patent number: D646687
    Type: Grant
    Filed: August 27, 2010
    Date of Patent: October 11, 2011
    Assignee: Compal Electronics, Inc.
    Inventors: Ta-Chang Chen, Mu-Te Chien