The Hong Kong University of Science and Technology

Kin On Johnny Sin

Kwok Tai Philip Mok

Wing Hung Ki

Ka Nang Leung

Rongxiang Wu

Xiangming Fang

An integrated capacitor can be fabricated with both electrodes formed by trenches for low resistance. According to one embodiment, the capacitor can comprise a first trench electrode, one or more dielectric layers, and a second trench electrode. The first trench electrode and the second trench electrode can be fabricated in different trenches to improve capacitance density and resistance of the integrated capacitor.

Method and apparatus for an integrated capacitor

A three stage amplifier is disclosed provided with a novel frequency compensation technique. Only a single feedback loop with a single compensation capacitance is provided. Instead of a conventional nested compensation technique, damping factor control is provided by means of a fourth gain stage in order to stabilize the amplifier. The resulting amplifier is particularly useful to drive large capacitive loads for low-voltage low-power applications.

Frequency compensation techniques for low-power multistage amplifiers

A method and apparatus are disclosed for the dimming control of a fluorescent lamp driven by an electronic ballast. A small portion (eg less than 15&deg;) of the phase of the input supply voltage is removed, and the precise amount of the phase removed is used to generate a switching signal that controls the switching frequency of the electronic ballast and hence the light power output. The switching frequency is generated by producing pulses of a width proportional to the amount of phase removed, integrating the pulses to produce a voltage proportional to the phase removed, converting that voltage to a current that varies with a frequency depending on the voltage, and using that varying current to generate the switching frequency.

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Hong Kong, China

Kin On Johnny Sin