Abstract:
A semiconductor memory device generates a control signal for regulating a potential of an internal power voltage when an extended mode register is set to adjust an operating speed and a tWR (time to write recovery) of a chip. The semiconductor memory device comprises an extended mode register setting unit and an internal power voltage generating unit. When an internal circuit enters into a specific mode for high-speed operation, the extended mode register setting unit outputs a plurality of internal power control signals to regulate a potential of an internal power voltage of the internal circuit. The internal power voltage generating unit generates an internal power voltage by regulating the potential of the internal power voltage in response to the plurality of internal power control signals.
Abstract:
A number of memory array units are placed on a die. Each memory array within a unit is coupled to a channel that includes one or more data lines coupled to a pad on the die. Each memory array unit utilizes a different channel. Memory array units are grouped together in pairs on the die to form memory array groups. The two channels of each memory array group form boundaries on the die. The pads coupled to each channel of a memory array group are positioned within those boundaries. The pads may be arranged such that the same pad layout can be used across different dies fabricated for use at different bus widths. In one embodiment, a set of the pads are used in applications where the die is configured for a first bus width and a portion of the pads used in the first bus width applications are not used in applications where the die is configured to for a second bus width. By providing additional pads, the die may be connected to external leads in different bus width configurations and with different external lead sequences without substantially increasing the length of the internal data bus.
Abstract:
Content addressable memory (CAM) devices use both hard and soft priority techniques to allocate entries of different priority therein. The priorities of multiple CAM array blocks within the CAM device may be programmed before or as entries are loaded therein and may be reprogrammed during operation as the allocation of entries within the CAM device changes. The allocation of entries may change in response to additions or deletions of entries or as entries are reprioritized. The CAM devices include preferred priority resolution circuits that can resolve competing soft and hard priorities between multiple hit signals that are generated in response to a search operation. Such hit signals may be active to reflect the presence of at least one matching entry within a CAM array block. The resolution of which active hit signal has the highest overall priority among many can be used to facilitate the identification of the location (e.g., array address and row address) of a highest priority matching entry within the entire CAM device. A priority resolution circuit may also resolve competing hard priorities between two or more active hit signals having equivalent soft priority. This aspect of the priority resolution circuit is provided so that an active hit signal having a highest overall priority can be resolved whenever multiple CAM array blocks having the same soft priority are detected as having matching entries therein during a search operation.
Abstract:
A CAM cell is disclosed that includes a comparator and two three-transistor (3T) DRAM cells connected to a pair of associated bit lines. Data is stored using intrinsic capacitance of each 3T DRAM cell, and is applied to the gate terminal of a pull-down transistor of the comparator. During refresh operations, inverted data values are written onto the bit lines, and subsequently written from the bit lines to the 3T DRAM cells. In ternary embodiments, an inverting refresh circuit is used to re-invert the inverted data values prior to being written to the 3T DRAM cells. In one embodiment, the 3T DRAM cells are cross-coupled to the bit lines, and the inverting refresh circuit transfers bits from one bit line to the other.
Abstract:
Ternary CAM cells are provided that have extremely small layout footprint size and efficient layout aspect ratios that enhance scalability. The cells also have high degrees of symmetry that facilitate high yield interconnections to bit, data and match lines. A 16T ternary CAM cell includes first and second pairs of access transistors that extend adjacent a first side of the cell, and first and second pairs of cross-coupled inverters that extend adjacent a second side of the cell. First and second halves of a 4T compare circuit are also provided. The first half of the 4T compare circuit is positioned so that is extends between the first pair of access transistors and the first pair of cross-coupled inverters. Similarly, the second half of the 4T compare circuit is positioned so that it extends between the second pair of access transistors and the second pair of cross-coupled inverters.
Abstract:
Content addressable memory (CAM) devices include at least one CAM array that is configured to identify at least one match between a new search word and entries therein by performing a staged compare operation that conserves bit line power by initially floating at least some of a plurality of bit lines in said CAM array and then driving the at least some of a plurality of bit lines with second bits of the new search word in response to detecting at least one partial match between first bits of the new search word and the entries in said CAM array.
Abstract:
A CAM system includes an integrated circuit chip having: logic & control circuitry, a CAM cell array, read/write access circuitry that performs read and write accesses to the CAM cell array, comparison access circuitry that performs comparison operations to the CAM cell array, a first voltage supply pad coupled to the read/write access circuitry; and a second voltage supply pad coupled to the comparison access circuitry. A first voltage supply, external to the integrated circuit chip, provides a first supply voltage to the first voltage supply pad, wherein the logic & control circuitry is powered by the first supply voltage. A second voltage supply, external to the integrated circuit chip, provides a second supply voltage to the second voltage supply pad, wherein at least a portion of the comparison access circuitry is powered by the second supply voltage, wherein the second supply voltage is less than the first supply voltage.
Abstract:
A content addressable memory array includes a plurality of rows of active CAM cells electrically coupled to a corresponding plurality of active match lines and at least one row of dummy cells, which are configured to generate an always-match condition on a dummy match line when the CAM array is undergoing a search operation. A match line pull-up circuit is provided. This match line pull-up circuit is electrically coupled to the plurality of active match lines and the dummy match line. The pull-up circuit is responsive to a calibration control signal that sets a pull-up strength of the match line pull-up circuit when the CAM array is undergoing the search operation. A sense amplifier, which is coupled to the match lines, includes a control circuit configured to adjust the calibration control signal in response to evaluating a first voltage on the dummy match line relative to a reference voltage.
Abstract:
Disclosed is a method of preparing sustained release microspheres by spray-drying liquids with different compositions for preparation the sustained release microspheres through an ultrasonic dual-feed nozzle. Unlike conventional methods of preparing sustained release microspheres by spray-drying a single liquid containing a biodegradable polymer, a drug, an additive and a solvent through a single-feed nozzle, the present method is characterized by simultaneously spray-drying two liquids with different compositions for preparation of the sustained release microspheres respectively through internal and external channels of an ultrasonic dual-feed nozzle to coat sprayed droplets through the internal channel with other sprayed droplets through the external channel. The present method is effective in achieving a low initial release and a desired continuous release.
Abstract:
Disclosed is an electrochromic device including at least one display region and at least one non-display region, which are separated from each other, the electrochromic device including a first substrate, a first electrode, an electrochromic layer, an electrolyte layer, optionally an ion storage layer, a second electrode, and a second substrate, which are sequentially formed, wherein the ion storage layer and/or the second electrode are patterned so as to prevent the ion storage layer and/or the second electrode from existing in part or all of said at least one display region; and a display device including the electrochromic device. In the electrochromic device, only the second substrate and electrolyte layer are located between the observer and the electrochromic layer, so that it is possible to prevent a contrast ratio from being degraded due to the ion storage layer and/or second electrode.