Abstract: An associative memory circuit including a first memristor, a second memristor, a fixed value resistor R, and an operational comparator. One terminal of the first memristor is a first input terminal of the associative memory circuit, and the other terminal of the first memristor is connected to a first input terminal of the operational comparator. One terminal of the second memristor is a second input terminal of the associative memory circuit, and the other terminal of the second memristor is connected to the first input terminal of the operational comparator. One terminal of the fixed value resistor is connected to the first input terminal of the operational comparator, and the other terminal of the fixed value resistor is connected to the ground. A second input terminal of the operational comparator is connected to a reference voltage.

Abstract: A CAM device for comparing a search key with a plurality of ternary words stored in a CAM array includes one or more population counters, a pre-compare memory, and a pre-compare circuit. The present embodiments reduce the power consumption of CAM devices during compare operations between a search key and ternary words stored in a CAM array by selectively enabling the match lines in the CAM array in response to pre-compare operations between a set of population counts corresponding to the masked search key and a set of population counts corresponding to the ternary words stored in the CAM array.

Abstract: A semiconductor storage device 1 includes: an input controller (3); and a content-addressable memory block (2) connected to the input controller (3). Each word circuit (4) of the content-addressable memory block (2) includes: a k-bit 1st-stage sub word (4a) connected to search line 1 (SL1) of the input controller (3); and an (n-k)-bit 2nd-stage sub word (4b) connected to search line 2 (SL2) of the input controller (3). The k-bit 1st-stage sub word (4a) and the (n-k)-bit 2nd-stage sub word (4b) are separated by a segmentation circuit (5). When the 1st-stage sub word outputs a match signal, the match result is stored in the segmentation circuit (5), and a plurality of local match circuits within the 2nd-stage sub word (4b) are operated.

Abstract: A content addressable memory (CAM) has a CAM array, a path selection circuit and a control circuit. The CAM array has a plurality of main columns of CAM cells and at least one redundant column of CAM cells. The path selection circuit receives an input search data, and outputs a plurality of bits of the input search data to a plurality of selected columns in the CAM array, respectively. The control circuit controls the path selection circuit to couple to the selected columns, and sets each CAM cell of at least one faulty column found in the main columns at a match state. The at least one faulty column is not included in the selected columns, and the at least one redundant column is included in the selected columns.

Abstract: A digital design and technique may be used to implement a Manhattan Nearest Neighbor content addressable memory function by augmenting a serial content addressable memory design with additional memory and counters for bit serially accumulating in parallel and subsequently comparing in parallel all the Manhattan distances between a serially inputted vector and all corresponding vectors resident in the CAM. Other distance measures, besides a Manhattan distance, may optionally be used in conjunction with similar techniques and designs.

Abstract: A content addressable memory (CAM) system includes one or more CAM cells, each including a bit cell to store a bit and a complementary bit, and a compare circuit to compare a reference input to the stored bit and to the stored complementary bit. The compare circuit may be implemented to compare a single-ended reference input to each of the stored bit and the complementary bit. The compare circuit may include a pass circuit to selectively provide the reference input to an output under control of the stored bit and the stored complementary bit, a pull-up circuit to selectively pull-up the output under control of the reference input and the stored complementary bit, and a pull-down circuit to selectively pull-down the output under control of the reference input and the stored bit. The reference input may be provided to multiple CAM cells, which may share compare circuitry.

Abstract: Embodiments of a Content Addressable Memory (CAM) enabling high-speed search and invalidate operations and methods of operation thereof are disclosed. In one embodiment, the CAM includes a CAM cell array including a number of CAM cells and a valid bit cell configured to generate a match indicator, and blocking circuitry configured to block an output of the valid bit cell from altering the match indicator during an invalidate process of a search and invalidate operation. Preferably, the output of the valid bit cell is blocked from affecting the match indicator for the CAM cell array beginning at a start of the invalidate process and continuing until an end of the search and invalidate operation.

Abstract: This invention discloses a 2T-string NOR-based CAM logic cell comprising two physical NAND cells connected in series with two horizontal WLs and one vertical BL and one vertical SL. Additionally, a sector of NOR-based CAM logic cell array is configured with N vertical cell strings each including M 2T-string NOR-based CAM logic cells connected in parallel sharing a local vertical SL and one dedicated vertical ML as an Operand word vertical page. Each 2T-string NOR-based CAM logic cell can be either a binary or ternary CAM cell associated with two or three physical states assigned to NAND cells' Vt levels for defining CAM logic states. Logic match of M-logic-bit inputs is found for at least one vertical page if the corresponding M 2T-string NOR-based CAM logic cells are in non-conduction state, providing M times faster Compare performance over the NAND-based CAM and 2 time faster than SRAM-based CAM.

Abstract: Electronic component including a ternary content-addressable memory component, configured to compare the input data items with a set of pre-recorded reference data words; the memory component incorporates a matrix of elementary cells arranged in lines and columns; each line incorporates cells in each of which is recorded one bit of one of the reference data words; the cells of a given column are dedicated to the comparison of the same bit of the input data word; each cell incorporates: two memory points storing the data representing the reference data bit; a comparison circuit connected to the memory points, with a comparison point of which the potential represents the comparison if the input data bit and the data stored in the memory points, and also incorporating a common comparison circuit to which are connected the comparison circuits of all or part of the cells of a given column; the comparison circuit incorporates terminals to which the bit from the input data word and its complement are applied.

Abstract: A CAM device includes a CAM array that can implement column redundancy in which a defective column segment in a selected block can be functionally replaced by a selected column segment of the same block, and/or by a spare column segment of the same block.

Abstract: The semiconductor device of the present invention includes a search memory mat having a configuration in which a location with which an entry address is registered is allocated in a y-axis direction, and key data is allocated in an x-axis direction and a control circuit connected to the search memory mat. In the search memory mat, a plurality of separate memories is formed such that a region to which the key data is allocated is separated into a plurality of regions along the y-axis direction. The control circuit includes an input unit to which the key data is input, a division unit which divides the key data input to the input unit into a plurality of pieces of key data, and a writing unit which allocates each piece of divided key data by the division unit into the separate memory using the divided key data as an address.

Abstract: An integrated circuit including a sense amplifier connected to a sense line is provided. The sense amplifier is configured to end a precharge phase of the sense line based on a state of the sense amplifier.

Abstract: The present invention provides a content addressable memory capable of higher frequency operation than conventional. When a search enable signal supplied from a search control circuit is asserted, each of search line drivers transfers search data to each CAM cell of a CAM memory array via a search line pair. The search line enable signal is transmitted to the search line drivers via a single control signal line coupled to the search control circuit. The control signal line is coupled to the search line drivers in such a manner that the search line enable signal passes through coupling nodes between the search line drivers and the control signal line in an arrangement order of the search line drivers from the side far away as viewed from match amplifiers.

Abstract: A memory cell includes a first transistor controlling writing of the first date by being in an on state, and holding of the first data by being in an off state, a second transistor in which a potential of one of a source and a drain is a potential of the second data and a potential of a gate is a potential of the first data, and a third transistor which has a conductivity type opposite to that of the second transistor, which has one of a source and a drain electrically connected to the other of the source and the drain of the second transistor, and in which a potential of a gate is a potential of the first data.

Abstract: A semiconductor memory device includes a memory portion that includes i (i is a natural number) sets each including j (j is a natural number of 2 or larger) arrays each including k (k is a natural number of 2 or larger) lines to each of which a first bit column of an address is assigned in advance; a comparison circuit; and a control circuit. The i×j lines to each of which a first bit column of an objective address is assigned in advance are searched more than once and less than or equal to j times with the use of the control circuit and a cache hit signal or a cache miss signal output from the selection circuit. In such a manner, the line storing the objective data is specified.

Abstract: A content addressable memory chip which can perform a high speed search with less error is provided. A match amplifier zone determines coincidence or non-coincidence of search data with data stored in the content addressable memory cells in an entry of a CAM cell array, according to the voltage of a match line. The match amplifier zone comprises one or more NMOS transistors and one or more PMOS transistors. The match amplifier zone has a dead zone to an input of a voltage of the match line, and has a property that no flow-through current is present in the match amplifier zone.

Abstract: An associative memory that can reduce search errors is provided. An associative memory includes R distance/time conversion circuits DT1 to DTR. The R distance/time conversion circuits DT1 to DTR each include a NAND circuit 40 and N bit stages 41 to 4k. The N bit stages 41 to 4k delay a signal from the NAND circuit 40 by longer delay time as the distance between reference data and search data is greater and oscillate the signal. Among R oscillation signals output from the distance/time conversion circuits DT1 to DTR, the earliest changing oscillation signal is detected as an oscillation signal for the Winner row.

Abstract: A method within a hybrid ternary content addressable memory (TCAM) includes comparing a first portion of a search word to a first portion of a stored word in a first TCAM stage. The method further includes interfacing an output of the first TCAM stage to an input of the second TCAM stage. The method also includes comparing a second portion of the search word to a second portion of the stored word in a second TCAM stage when the first portion of the search word matches the first portion of the stored word. The first TCAM stage is different from the second TCAM stage.

Abstract: A ternary content addressable memory (TCAM) is formed by TCAM cells that are arranged in an array. Each TCAM cell includes a first and second SRAM cells and a comparator. The SRAM cells predominantly in use have a horizontal topology with a rectangular perimeter defined by longer and shorter side edges. The match lines for the TCAM extend across the array, and are coupled to TCAM cells along an array column. The bit lines extend across the array, and coupled to TCAM cells along an array row. Each match line is oriented in a first direction (the column direction) that is parallel to the shorter side edge of the horizontal topology layout for the SRAM cells in each CAM cell. Each bit line is oriented in a second direction (the row direction) that is parallel to the longer side edge of the horizontal topology layout for the SRAM cells in each CAM cell.

Abstract: A memory device including: a memory cell array including normal memory cells and spare memory cells arranged in rows and columns including normal columns including the normal memory cells and at least one spare column including spare memory cells, a segment match determining circuit configured to compare a segment address with row address information corresponding to a failed segment and to generate a load control signal, and a column match determining circuit configured to compare column address information corresponding to a failed column in response to the load control signal with a column address and to generate a column address replacement control signal, wherein the memory cells connected to fail columns of the fail segment are replaced with memory cells connected to columns of the spare memory cells in response to the column address replacement control signal.

Abstract: Low leakage CAMs and method of searching low leakage CAMs. The method includes performing a pre-search and compare on a small number of pre-search bits with pre-search CAM cells powered to normal voltage levels at all times while the main-search CAM cells are powered to a lower voltage level. Only if a match is detected on the pre-search bits are the main-search CAM cells powered-up to normal voltage levels and the search of the main-search bits activated. The main-search CAM cells are powered to normal voltage levels during read and write operations.

Abstract: There is a need to highly integrate a circuit area of content addressable memory (CAM) and ensure faster operation thereof. A priority encoder and row decoder portion shares a row address register including more than one row. Each row of the row address register corresponds to each entry of a TCAM array mat and retains each address. Each row of the row address register corresponds to each word line and match line of the TCAM array mat. Writing data to the TCAM array mat activates word line for a row retained in the row address register corresponding to a specified address. Searching for the TCAM array mat activates a match line for the TCAM array mat. The row address register for the corresponding row stores the address of an entry for the TCAM array mat matching search data.

Abstract: Aspects of the disclosure pertain to a system and method for promoting improved error detection efficiency in a Content-Addressable Memory (CAM). The system and method provide CAM continuous error detection with interleave parity. The system continuously monitors for changes in cell contents and, when (e.g., as soon as) a soft error occurs, the error detection output bit for that entry will change, causing an error flag at chip level. The system can then immediately stop compare operations and rewrite the failing entry. Separate read operations are not needed to check for errors, thereby decreasing overall dynamic power usage and increasing possible search frequency for the system.

Abstract: An embodiment of the invention provides a binary CAM cell. The binary CAM cell includes a storage circuit, a first discharging circuit, and a second discharging circuit. The storage circuit is configured to provide a first stored bit and a second stored bit, which are complimentary bits of each other. The first discharging circuit is configured to either discharge or not discharge a match line according to the first stored bit provided by the storage circuit and a first searched bit provided by a first search line. The first discharging circuit includes a first PMOS transistor. The second discharging circuit is configured to either discharge or not discharge the match line according to the second stored bit provided by the storage circuit and a second searched bit provided by a second search line. The second discharging circuit includes a second PMOS transistor.

Abstract: A content addressable memory (CAM) device having any number of rows, each of the rows including a match line connected to a plurality of CAM cells, a match line detector circuit, and an incremental match line charge circuit. The detector circuit generates a feedback signal based on a detected match line voltage. The charge circuit partially pre-charges the match line to an intermediate voltage during a pre-charge phase of a compare operation, and then selectively charges the match line higher towards a supply voltage in response to the feedback signal.

Abstract: A content addressable memory device based on an extremely compact design, potentially as small as 16F2 per memory cell. One embodiment is based on cells having two memory storage elements, such as RRAM elements. Each RRAM element and a respective FET are connected in series between a common matchline and a respective bitline. Cell content for each cell is matched against a bit of a search word by applying voltages to the respective bitlines dependent upon bit value and causing one of the two RRAM elements for each cell to discharge the matchline over a low resistance path in event of mismatch between the cell content and the bit. If no “quick” discharge occurs for multiple cells of a row, then a match is detected. In addition, a matchline recharge path to a high voltage bitline is substantially eliminated by controlling the FETs with specific wordline voltages.

Abstract: A cache memory which can operate with less power consumption and has an improved cache hit rate and a method for driving the cache memory are provided. Two data storage portions (a first storage portion and a second storage portion) and one data transfer portion are provided in one memory cell in a memory set included in a cache memory, and arranged so that data can be transferred between the two storage portions via the data transfer portion. One of the two data storage portions can store data input from the outside and output data to a comparison circuit paired with the memory set.

Abstract: A circuit according to embodiments includes: a plurality of bit-string comparators each of which includes a plurality of single-bit comparators each of which includes first and second input terminals, first and second match-determination terminals, and a memory storing data and inverted data in a pair, the first input terminal being connected to a respective search line, the second input terminal being connected to an inverted search line being paired with the respective search line, and a matching line connecting the first and second match-determination terminals of the single-bit comparators; a pre-charge transistor of which source is connected to a supply voltage line; a common matching line connected to a drain of the pre-charge transistor and the matching lines of the bit-string comparators; and an output inverter of which input is connected to the common matching line.

Abstract: Incoming data packets are often processed according to their origination or destination port. In order to efficiently determine applicable rules based on port values, ranges are stored in association with corresponding rules in a ternary memory. In order to reduce the amount of required memory to store these ranges, extra unused bits of the ACL that includes the rule can be used. Further, to maximize the storage capability of these limited extra bits, most common ranges can be stored in one or more bit partitions depending on whether they encompass other most common ranges to be stored in the extra bits. Through partitioning and intelligent bit assignment, many ranges can be stored in the limited extra bits, and can each remain individually addressable.

Abstract: The present invention provides a content addressable memory capable of higher frequency operation than conventional. When a search enable signal supplied from a search control circuit is asserted, each of search line drivers transfers search data to each CAM cell of a CAM memory array via a search line pair. The search line enable signal is transmitted to the search line drivers via a single control signal line coupled to the search control circuit. The control signal line is coupled to the search line drivers in such a manner that the search line enable signal passes through coupling nodes between the search line drivers and the control signal line in an arrangement order of the search line drivers from the side far away as viewed from match amplifiers.

Abstract: Electronic component including a ternary content-addressable memory component, configured to compare the input data items with a set of pre-recorded reference data words; the memory component incorporates a matrix of elementary cells arranged in lines and columns; each line incorporates cells in each of which is recorded one bit of one of the reference data words; the cells of a given column are dedicated to the comparison of the same bit of the input data word; each cell incorporates: two memory points storing the data representing the reference data bit; a comparison circuit connected to the memory points, with a comparison point of which the potential represents the comparison if the input data bit and the data stored in the memory points, and also incorporating a common comparison circuit to which are connected the comparison circuits of all or part of the cells of a given column; the comparison circuit incorporates terminals to which the bit from the input data word and its complement are applied.

Abstract: A ternary content-addressable cell is configured to compare an input binary data item present on an input terminal with two reference binary data items, and to output a match signal on a match line. The cell includes: a first storage circuit (storing a potential representing the first reference binary data item) and a second storage cell (storing a potential representing the second reference binary data item). A comparison circuit is connected to the first and second storage circuits and to the input terminal SL. A comparison node presents a potential representing the comparison of the input binary data item with the first and second reference data items. The comparison node is connected to an output stage, and the output stage is connected to the match line. The signal on the match line is based on the potential of the comparison node.

Abstract: To provide a semiconductor device whose power can be turned off without the need for a peripheral circuit for data to escape temporarily and in which stored data is not lost even in an off state of the power of the device, and a memory device including the semiconductor device. In a holding circuit of the semiconductor device, a transistor that includes a semiconductor layer (at least a channel formation region) including an oxide semiconductor material with which small off-state current can be achieved is used. Further, the semiconductor device includes a switching element which enables a comparison circuit in which comparison between data stored in the holding circuit and reference data input from the outside does not need to be performed to become forcibly inactive.

Abstract: A method within a ternary content addressable memory (TCAM) includes receiving a match line output from a previous TCAM stage at a gate of a pull-up transistor of a current TCAM stage and at a gate of a pull-down transistor of the current TCAM stage. The method sets a match line bar at the current TCAM stage to a low value, via the pull-down transistor, when the match line output from the previous TCAM stage indicates a mismatch. The method also sets the match line bar at the current TCAM stage to a high value, via the pull-up transistor, when the match line output from the previous TCAM stage indicates a match.

Abstract: There is a need to highly integrate a circuit area of content addressable memory (CAM) and ensure faster operation thereof. A priority encoder and row decoder portion shares a row address register including more than one row. Each row of the row address register corresponds to each entry of a TCAM array mat and retains each address. Each row of the row address register corresponds to each word line and match line of the TCAM array mat. Writing data to the TCAM array mat activates word line for a row retained in the row address register corresponding to a specified address. Searching for the TCAM array mat activates a match line for the TCAM array mat. The row address register for the corresponding row stores the address of an entry for the TCAM array mat matching search data.

Abstract: In one embodiment, a first search operation is performed based on a base lookup word on a first plurality of content-addressable memory entries of an overall plurality of priority-ordered content-addressable memory entries to identify a first matching entry and a corresponding first overall search position of the first matching entry within the overall plurality of priority-ordered content-addressable memory entries. A second search operation is performed based on the base lookup word on a second plurality of content-addressable memory entries of the overall plurality of priority-ordered content-addressable memory entries to identify a second matching entry and a corresponding second overall search position of the second matching entry within the overall plurality of priority-ordered content-addressable memory entries. The corresponding first overall search position is compared to the corresponding second overall search position to determine the overall search result.

Abstract: A content-addressable memory (CAM) with computational capability is described. The CAM includes an array of CAM cells arranged in rows and columns with a pair of search lines associated with each column of the array and a match line associated with each row of the array. The array of CAM cells is configured to implement, for a given cycle, either a read operation of data contained in a single selected column, or one of a plurality of different bitwise logical operations on data contained in multiple selected columns. All of the pairs of search lines in the columns of the array are configured to a certain state to implement the read operation or one of the plurality of different bitwise logical operations. A result of the read operation or one of the plurality of different bitwise logical operations is outputted onto all of the match lines in the array.

Abstract: A memory under repair having variable size blocks of failed memory addresses is connected to a TCAM comprising cells storing data values of ranges of the failed memory addresses in the memory under repair. The TCAM is connected to a virtual address line. Matchlines in the TCAM drive wordlines in a RAM connected to the TCAM. Each entry in the TCAM corresponds to one entry in the RAM and represents a single block of failed memory addresses. A first input of an XOR gate in an integrated circuit device is operatively connected to the RAM and a second input is operatively connected to the virtual address line. Responsive to a virtual address being an address in one of the ranges of failed memory addresses, the XOR gate calculates a physical memory address redirecting the virtual address to an unused good memory location in place of the failed memory address.

Abstract: A memory device can include a memory array section; a write first-in-first-out circuit (FIFO) configured to transfer write data to the memory array portion; at least one store circuit configured to store a copy of at least a portion of the write data stored in the write FIFO; and an address compare section configured to store write addresses corresponding to the write data of the forwarding circuit.

Abstract: A content addressable memory chip which can perform a high speed search with less error is provided. A match amplifier zone determines coincidence or non-coincidence of search data with data stored in the content addressable memory cells in an entry of a CAM cell array, according to the voltage of a match line. The match amplifier zone comprises one or more NMOS transistors and one or more PMOS transistors. The match amplifier zone has a dead zone to an input of a voltage of the match line, and has a property that no flow-through current is present in the match amplifier zone.

Abstract: A content addressable memory (CAM) device to dynamically reduces power consumption between a search key and data stored in a plurality of CAM blocks by selectively disabling a number of CAM blocks, requested for the search operation by an external network processor, based upon the contents of the search key.

Abstract: A multi-priority encoder includes a plurality of interconnected, single-priority encoders arranged in descending priority order. The multi-priority encoder includes circuitry for blocking a match output by a lower level single-priority encoder if a higher level single-priority encoder outputs a match output. Match data is received from a content addressable memory, and the priority encoder includes address encoding circuitry for outputting the address locations of each highest priority match line flagged by the highest priority indicator. Each single-priority encoder includes a highest priority indicator which has a plurality of indicator segments, each indicator segment being associated with a match line input.

Abstract: A content addressable memory (CAM) suppresses an indication of a match in response to determining that the entry that stores data matching received compare data is the subject of a write operation. To suppress the indication, an address decoder decodes a write address associated with the write operation to determine the entry of the CAM that is the subject of the write operation, and provides control signaling indicative of the determined entry. The CAM uses the control signaling to suppress any match indications for the entry being written, thereby preventing erroneous match indications.

Abstract: A ternary content addressable memory (TCAM) has at least one TCAM cell comprising first and second memory bitcells for storing first and second bit values representing a cell state comprising one of a first cell state, a second cell state and a mask cell state. The first and second memory bitcells share a pair of bitlines for accessing the first and second bit values. Access control circuitry is provided for triggering, in response to a clock signal, a read or write access to the first memory bitcell during a first portion of a clock cycle and triggering a read access or write access to the second read bitcell during a second portion of the clock cycle.

Abstract: A shared stack dual-phase CAM cell is provided. The CAM cell includes at least first and second stacks that share a single pair of pull-down transistors. At least one pair of pull-down transistors can thus be eliminated, reducing the area and power consumption of the CAM cell. Sharing of the single pair of pull-down transistors is enabled by time-staggered pre-charge and compare operations such that the pre-charge interval of the first stack corresponds to the compare interval of the second stack, and vice versa.

Abstract: Disclosed are a memory system and an associated operating method. In the system, a first memory array comprises first memory cells requiring a range of time delays between wordline activating and bitline sensing. A delay signal generator delays an input signal by a selected time delay (i.e., a long time delay corresponding to statistically slow memory cells) and outputs a delay signal for read operation timing to ensure read functionality for statistically slow and faster memory cells. To accomplish this, the delay signal generator comprises a second memory array having second memory cells with the same design as the first memory cells. Transistors within the second memory cells are controlled by a lower gate voltage than transistors within the first memory cells in order to mimic the effect of higher threshold voltages, which result in longer time delays and which can be associated with the statistically slow first memory cells.

Abstract: In one embodiment, a first search operation is performed based on a base lookup word on a first plurality of content-addressable memory entries of an overall plurality of priority-ordered content-addressable memory entries to identify a first matching entry and a corresponding first overall search position of the first matching entry within the overall plurality of priority-ordered content-addressable memory entries. A second search operation is performed based on the base lookup word on a second plurality of content-addressable memory entries of the overall plurality of priority-ordered content-addressable memory entries to identify a second matching entry and a corresponding second overall search position of the second matching entry within the overall plurality of priority-ordered content-addressable memory entries. The corresponding first overall search position is compared to the corresponding second overall search position to determine the overall search result.

Abstract: According to one disclosed embodiment, a content-addressable memory (CAM) system configured for reduced power consumption includes a sensing circuit utilized to apply a sense voltage to a matchline of the CAM system, a valid bit cell coupled to the matchline, and a power cut-off circuit configured to isolate the sense voltage from the matchline when an invalid validity state is stored in the valid bit cell, thereby reducing power consumption by the CAM system. In one embodiment, the power cut-off circuit isolates the sense voltage from the matchline by decoupling the sensing circuit from a control signal when an invalid validity state is stored in the valid bit cell.

Abstract: An embodiment of the invention includes a ternary content addressable memory (TCAM) that has input search data bits, TCAM words and range search input data bits. Each TCAM word is operable to store a match pattern and provide a match output. The match output indicates a match when the match pattern of the TCAM word matches the TCAM input search data bits. The range search input data bits are separated into groups. Each group has a bit width N where N is the number of range search input data bits. For the match pattern in each group, there is a Boolean function that uses the N range of search input data bits. (2N)/2 TCAM bits are provided for each TCAM word. 2N internal TCAM search lines are operable to search the (2N)/2 TCAM bits. Decoder logic is associated with each group that decodes the N range search input data bits.

Abstract: An embodiment of the invention includes first and second Ternary Content Addressable Memories (TCAMs), a first vector, and TCAM match-merge unit. Each of the TCAMs includes a plurality of words, stores TCAM match entries and outputs a TCAM match signal for each word in the plurality of words. The first vector includes first TCAM group enable register bits. An enabling value on the first TCAM register bit indicates that the first TCAM match signal and the neighboring first TCAM match are in the same TCAM group. The TCAM match-merge unit receives the first TCAM match signal from each of the words and the first vector and outputs a first TCAM group match signal for each of the words. The TCAM match-merge unit outputs a match indication when any of the TCAM match signals indicate a match and outputs a mismatch when none of the TCAM match signals match.