Abstract: This patent describes a method for switching search-lines in a Content Addressable Memory (CAM) asynchronously to improve CAM speed and reduce CAM noise without affecting its power performance. This is accomplished by resetting the match-lines prior to initiating a search and then applying a search word to the search-lines. A reference match-line is provided to generate the timing for the search operation and provide the timing for the asynchronous application of the search data on the SLs. Additional noise reduction is achieved through the staggering of the search data application on the SLs through programmable delay elements.

Abstract: A dual-ported AND-type match-line circuit includes at least one dual-ported dynamic AND gate. The dual-ported dynamic AND gate includes a group of CAM cells and a dual-ported dynamic circuit. A group of CAM cells connected to a dual-ported dynamic circuit and to the GND. The dual-ported dynamic circuit is connected to a group of CAM cells. The dual-ported dynamic circuit includes a setting circuit, a first directing circuit, a second directing circuit, a first AND dynamic output circuit and a second AND dynamic output circuit.

Abstract: A technique is presented for implementing a content addressable memory (CAM) function using traditional memory, where the input data is serially loaded into a serial CAM. Various additions, which allow for predicting the result of a serial CAM access coincident with the completion of serially inputting the data are also presented.

Abstract: A memory includes at least one write bit line and a plurality of memory cells. The at least one write bit line is configured to carry a write bit signal. The plurality of memory cells are arranged in a column and are configured to be selectively coupled to the at least one write bit line. The plurality of memory cells are configured to be selectively read or written in a first phase of a cycle and selectively read or written in a second phase of the cycle using the at least one write bit line.

Abstract: A semiconductor device according to an embodiment of the invention includes: a plurality of field effect transistors; and a plurality of logic circuits composed of the field effect transistors, the field effect transistors each including: first and second drain regions formed away from each other; at least one source region formed between the first and second drain regions; and a plurality of gate electrodes formed between the first drain region and the source region and between the second drain region and the source region.

Abstract: A semiconductor memory device including a dynamic random access memory (DRAM) cell and a ternary content addressable memory (TCAM) cell is disclosed. The DRAM cell may include a data storing portion and a data read portion. The data storing portion and data read portion comprising p-channel junction field effect transistors. The TCAM cell including an x-cell, y-cell, and comparator circuit. The x-cell, y-cell, and comparator circuits comprising p-channel JFETs.

Abstract: Systems, devices, and methods, including executable instructions are provided for content addressable memory (CAM). One method includes writing entries, including a type field, to a ternary content addressable memory (TCAM). The method includes marking certain entries as valid. The method includes precharging match lines associated with the entries when an entry is valid and based on a type selection.

Abstract: Hybrid carbon nanotube FET (CNFET), static ram (SRAM) and method of making same. A static ram memory cell has two cross-coupled semiconductor-type field effect transistors (FETs) and two nanotube FETs (NTFETs), each having a channel region made of at least one semiconductive nanotube, a first NTFET connected to the drain or source of the first semiconductor-type FET and the second NTFET connected to the drain or source of the second semiconductor-type FET.

Abstract: A method and apparatus for adaptive buffer sizing adjusts the size of the buffer at different levels using a “high water mark” to different levels for different system conditions. The high water mark is used by the buffer logic as an indication of when to assert the buffer “Full” flag. In turn, the full flag is used by the instruction fetch logic as an indication of when to stop fetching further instructions.

Abstract: A memory cell for use in a content-addressable memory comprises a first latch and a second latch. The first latch is operative to store a first bit associated with a first stored word, while the second latch is operative to store a second bit associated with a second stored word. The first and second latches collectively comprise a plurality of latch transistors. Each of the latch transistors comprises a respective channel. The channels of the latch transistors are oriented in substantially the same direction, resulting in a very compact memory cell implementation.

Abstract: A combo memory cell having a SRAM cell and a mask-ROM code programmer. The SRAM cell comprises first and second inverters. The first inverter comprises a first PMOS transistor and a first NMOS transistor. Gates of the first PMOS and NMOS transistors are commonly connected to a first input node and drains thereof commonly connected to a first output node. The second inverter comprises a second PMOS transistor and a second NMOS transistor. Gates of the second PMOS and NMOS transistors are commonly connected to a second input node and drains thereof commonly connected to a second output node. The first input node and the second output node are connected, as are the second input node and the first output node. The mask-ROM code programmer is coupled to the sources of the first and second PMOS transistors or the first and second NMOS transistors.

Abstract: Methods and apparatuses to decrease power consumption and reduce leakage current of integrated circuits are disclosed. New leakage power saving techniques for various types of integrated circuits, including cache memory circuits, are discussed. Embodiments comprise methods and apparatuses to reduce power consumption in integrated circuits by using virtual voltage rails, or virtual power rails, to supply power to integrated circuit loads. The methods and apparatuses generally involve using one or two virtual power control devices to “head” and “foot”, or sandwich, the integrated circuit loads from firm power supply rails. In these method embodiments, one or more elements sense the voltage of the virtual power rails, or nodes, and make adjustments to control the voltage at certain “virtual” voltage potentials. While controlling the voltage in this manner, the virtual power control devices may serve to restrict unnecessary current flow through the integrated circuit loads.

Abstract: According to an aspect of the invention there is provided a semiconductor memory device, including a first inverter being composed of a first P-channel MOS transistor, a first N-channel MOS transistor, a second inverter being composed of a second p-channel MOS transistor and a second N-channel transistor, a data-retaining portion having a third N-channel MOS transistor, a fourth N-channel MOS transistor, a fifth N-channel MOS transistor and a sixth N-channel MOS transistor, a data-reading portion for reading out data stored in the data-retaining portion via a first bit line, including at least one N-channel MOS transistor, wherein gate widths of the fifth N-channel MOS transistor and the sixth N-channel MOS transistor, respectively, is larger than gate widths of the first N-channel MOS transistor, the second N-channel MOS transistor, the third N-channel MOS transistor, the fourth N-channel MOS transistor, the first P-channel MOS transistor and the second P-channel MOS transistor, respectively.

Abstract: A CAM cell array according to embodiments of the present invention include an array of CAM cells, each of the CAM cells comprising a first cell, the first cell including a non-volatile storage element coupled to at least one first data line and a match line; a match line controller coupled to the match line; and a data line controller coupled to the data lines, wherein a write operation is performed by changing a state of the non-volatile storage element by providing data to the at least one data line, wherein a read operation is performed by determining the state of the non-volatile storage element through the at least one data line, and wherein a comparison operation is performed by applying data to the at least one data line and determining a match condition on the match line.

Abstract: A differential non-volatile content addressable memory array has a differential non-volatile content addressable memory cell which uses a pair of non-volatile storage elements. Each of the non-volatile storage elements can be a split-gate floating gate transistor or a stack gate floating gate transistor having a first terminal, a second terminal, a channel therebetween and a floating gate over at least a portion of the channel to control the conduction of electrons in the channel, and a control gate. The floating gate storage transistor can be in one of two states: a first state, such as erase, in which current can flow between the first terminal and the second terminal, and a second state, such as programmed, in which substantially no current flows between the first terminal and the second terminal. A pair of differential compare data lines connects to the control gate of each of the pair of non-volatile floating gate transistors.

Abstract: A CAM cell is provided that includes: an SRAM cell adapted to store a bit; a data line adapted to provide a corresponding comparand bit; an XOR gate adapted to XOR the stored bit and the comparand bit to provide an XOR output, and a switch adapted to close in response to the XOR output.

Abstract: In one embodiment, a CAM is provided that includes; a plurality of memory cells grouped to store a word, wherein the memory cells are organized into a plurality of ripple groups, each ripple group including a complex logic gate configured to determine whether a stored content for the ripple group's memory cells matches a corresponding portion of a comparand word if an enable input for the ripple group is asserted, each complex logic gate asserting an output if the determination indicates a match, the ripple groups being arranged from a first ripple group to a last ripple group such that the output from the first ripple group's complex logic gate functions as the enable input for a second ripple group's complex logic gate and so on such that an output from a next-to-last ripple group's complex logic gate functions as the enable input for the last ripple group's complex logic gate.

Abstract: A sensing circuit for use with a CAM circuit including multiple match lines and multiple CAM cells connected to the match lines includes at least one charge sharing circuit and at least one switching circuit connected to the charge sharing circuit. The switching circuit is operative to selectively connect the charge sharing circuit to a corresponding one of the match lines as a function of a first control signal supplied to the switching circuit. The sensing circuit further includes at least one comparator circuit connected to the corresponding match line and operative to generate an output signal indicative of a match between search data supplied to at least a given one of the CAM cells connected to the corresponding match line and data stored in the given CAM cell. The charge sharing circuit is operative to remove an amount of charge on the corresponding match line so as to reduce a voltage on the corresponding match line in conjunction with a search operation of the CAM cell.