Company Filing History:
4 out of 753 
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Years Active: 2009-2016
Title: Innovations of Yu Cheng Chang
Introduction
Yu Cheng Chang is a notable inventor based in Cupertino, CA (US). He has made significant contributions to the field of electronics, particularly in LED driver technology. With a total of 6 patents to his name, his work reflects a commitment to innovation and efficiency.
Latest Patents
One of his latest patents is the Adaptive Switch Mode LED Driver. This invention provides an intelligent approach to driving multiple strings of LEDs. The LED driver determines an optimal current level for each LED channel from a limited set of allowed currents. The LDO driver then determines a PWM duty cycle for driving the LEDs in each channel, ensuring precise brightness control. This technology minimizes power dissipation in the LDO circuits while maintaining currents within a limited range. Additionally, a sample and hold LDO allows PWM control over extreme duty cycles with a very fast dynamic response. Fault protection circuitry ensures fault-free startup and operation of the LED driver.
Another significant patent is the Voltage/Current Control Apparatus and Method. This apparatus includes a low-side field effect transistor (FET) and a high-side FET, along with a gate driver integrated circuit (IC), a sample and hold circuit, and a comparator. The comparator produces a trigger signal when the sum of the first and second input signals equals the sum of the third and fourth input signals. This trigger signal initiates a new cycle by turning the gate of the high-side FET 'on' and the gate of the low-side FET 'off'.
Career Highlights
Yu Cheng Chang has worked with prominent companies in the semiconductor industry, including Alpha & Omega Semiconductor Corporation and Iwatt Inc. His experience in these organizations has contributed to his expertise in developing innovative electronic solutions.
Collaborations
Throughout his career, Yu has collaborated with talented individuals such as Xuecheng Jin and Yang Li. These collaborations have likely fostered a creative environment that encourages the development of groundbreaking technologies.
Conclusion
Yu Cheng Chang's contributions to the field of electronics, particularly in LED driver technology, showcase his innovative spirit and dedication to advancing technology. His patents reflect a deep understanding of electronic systems and a commitment to improving efficiency and performance.