摘要:
A 4T static RAM cell (10) comprising a flip-flop with two pull-down transistors (18, 20) and two pass-gate transistors (12, 14) is fabaricated employing two separate gate oxide formations (74, 76) and associated separate polysilicon depositions (52a -b, 56). Two reduced area contacts (58, 60) connect to the nodes (26, 30) of the circuit (10). The reduced area butting contacts comprise vertically-disposed, doped polysilicon plugs (94), which intersect and electrically interconnect buried polysilicon layers (load poly 88, gate poly 52a) with doped silicon regions (80) in a bottom layer. Adding the processing steps of forming separate gate oxides for the pull-down and pass-gate transistors results in a smaller cell area and reduces the requirements of the contacts from three to two. Further, the separate gate oxidations permit independent optimization of the pull-down and pass-gate transistors.
摘要:
A reduced area butting contact structure (10') is provided, which is especially suited for four-transistor static RAM cells. A structure is formed which includes a doped silicon region and one or more layers of polysilicon and oxide situated thereabove, one of which layers of polysilicon may be a gate polysilicon. An anisotropic etch is then performed through all upper layers including any upper polysilicon layers which may be present, but stopping at the doped silicon region and any gate polysilicon layers present, to form a contact hole (26'). The contact hole is filled with a conductive plug (32) of a material such as tungsten or polysilicon and etched back. In either case, contact with all polysilicon layers present and the doped silicon region is made. In the anisotropic etching process, a two-step etch is employed. The first etch is non-specific as to material, etching all relevant materials (polysilicon and oxide) at substantially the same rate and is continued through any upper polysilicon layers, but is terminated prior to etching the doped silicon region or any gate polysilicon layers (22). The second etch is specific as to material, etching silicon dioxide faster than polysilicon or silicon, and thus stops at the gate polysilicon layer and the doped silicon region.
摘要:
A method and apparatus for clock signal noise shaping are described. Embodiments of a clock circuit include a filter coupled to receive an input clock signal and to provide an output clock signal. The filter filters noise of the input clock signal to shape the noise to provide the output clock signal. In a method for adjustment of phase noise, input clock signaling having the phase noise is obtained, and the input clock signal is filtered to adjust the phase noise to provide output clock signaling.
摘要:
A RAMDAC circuit drives a display device so as display multiple modes of color depth and display resolution in a single display frame without sacrificing resolution of the higher-resolution mode, and adjusts the output pixel rate to match that of the display mode being display on a pixel-by-pixel basis. The RAMDAC circuit switches between two graphics modes on-the-fly on a pixel-by-pixel basis in accordance with mode control bits stored in the pixel data. Furthermore, the RAMDAC circuit switches between two output pixel rates such that the amount of video memory used for any predefined screen area remains constant even though the output pixel rate and resolution are dynamically adjusted. In a preferred embodiment a display mode signal is embedded in the display data such that the display data, including the mode signal, comprises one byte of data for each display pixel when the mode signal specifies the first display mode, and comprises two bytes of data for each display pixel when the mode signal specifies the second display mode.
摘要:
Multi-mode charger device for charging portable devices and methods of charging portable devices are described. In an embodiment, a multi-mode charger device has mode blocks respectively associated with modes of operation which are coupled to a switch module. The switch module is for coupling a selected one of the mode blocks to a peripheral bus and to decouple the mode blocks remaining from the peripheral bus. A first mode of the modes of operation is a pass through mode. A second mode of the modes of operation is a first charging mode. A third mode of the modes of operation is a second charging mode. The first charging mode and the second charging mode are different from one another.
摘要:
Multi-mode charger device for charging portable devices and methods of charging portable devices are described. In an embodiment, a multi-mode charger device has mode blocks respectively associated with modes of operation which are coupled to a switch module. The switch module is for coupling a selected one of the mode blocks to a peripheral bus and to decouple the mode blocks remaining from the peripheral bus. A first mode of the modes of operation is a pass through mode. A second mode of the modes of operation is a first charging mode. A third mode of the modes of operation is a second charging mode. The first charging mode and the second charging mode are different from one another.