Abstract: An integrated circuit for driving high-voltage LED lamps is applied to a rectified alternative current (AC) power and a plurality of LED stacks. The integrated circuit includes a control unit, a plurality of current-clamping units which electrically connect to the control unit and the LED stacks respectively, and a plurality of current-sensing units which electrically connect to the current-clamping units and the control unit. When the rectified power is switched on, the current-sensing unit constantly monitors the electrical current flowing through the respective current-clamping unit and feeds back the monitored data to the control unit. The control unit sequentially switches on or off the current-clamping units according to the combinatorial logic state of the monitored data.

Abstract: The present invention discloses a fabrication method and structure of spiral RF inductor on porous glass substrate. Thick porous silicon layer is natively formed on a silicon wafer by anodic etching the silicon material to a high degree of porosity. The porous silicon is than thermally oxidized at high temperature converting it into porous glass texture. The oxidation rate can be rapid due to open pore character of the etched structure, which allows oxidizing agents to penetrate deeply into the wafer. If the porosity is large enough, the pores will not be sealed by the expansion of oxide during the oxidation, which results a porous structure of glass-and-air mixture of low relative dielectric constant slightly over a value of 2. The final holes appear on the wafer surface can be sealed by CVD coating step, if necessary. This ultra-flat, low-k, silicon-based substrate allows RF spiral inductor to be made on its surface with excellently low loss, or high Q value.

Abstract: An infrared photodetector structure with voltage-tunable and -switchable photoresponses constructed of superlattices and blocking barriers. The photoresponses of the double-superlattice structure are also insensitive to the operating temperature changes. By using GaAs/AlxGa1-xAs system, the feasibility of this idea is verified. In the embodiment, the photoresponses can be switched between 6˜8.5 and 7.5˜12 m by the bias polarity and are also tunable by the bias magnitude in each detection wavelength range. In addition, the photoresponses are insensitive to operating temperatures ranging from 20 to 80 K. For the SLIP with few periods, the responsivity may be higher than the one with many periods and the operational temperature is higher. These results show the invention can be useful in the design of multicolor imaging systems.