摘要:
According to one embodiment, the write circuitry of a content addressable memory (CAM) can include periphery circuits (102) that generate data signals (112) and write control signals (118) that connect over some distance to CAM core circuits (104). CAM core circuits (104) may include bitline write driver circuits (106), a write control circuit (108), and CAM cells (110). Write control signals (118) may include a signal surrounded by its complements and be positioned such that a routing of the write control signal is as long as the longest of the data signals (112).
摘要:
A single ended simplex dual port memory cell is described. One port of the memory cell is dedicated for writing operations and the other port of the memory cell is dedicated for reading operations. A bit of data received from the first port can be stored in the memory cell. The second port can detect the memory cell contents substantially simultaneously as the memory cell is storing a bit of data from the first port. Each port is optimized for its respective dedicated operation. In other words, one port is optimized for write operations and the other port is optimized for read operations. Because one port of the memory cell is optimized for write operations and the other port of the memory cell is optimized for read operations, the cell does not require multiple wordline voltages for each port.
摘要:
A content addressable memory (CAM) (100) can include a number of CAM entries (102-0 to 102-n). Match indications from CAM entries (102-0 to 102-n) and mismatch indications from complementing circuits (106-0 and 106-n) can be supplied to a switching circuit (108). Mismatch indications can indicate if an entry mismatches data when compared with a comparand (104). In one mode of operation, a switching circuit (108) can provide match indications on a number of switch outputs (SW0 to SWn). In another mode of operation, switching circuit (108) can provide mismatch indications on a number of switch outputs (SW0 to SWn).
摘要:
A single ended simplex dual port memory cell is described. One port of the memory cell is dedicated for writing operations and the other port of the memory cell is dedicated for reading operations. A bit of data received from the first port can be stored in the memory cell. The second port can detect the memory cell contents substantially simultaneously as the memory cell is storing a bit of data from the first port. Each port is optimized for its respective dedicated operation. In other words, one port is optimized for write operations and the other port is optimized for read operations. Because one port of the memory cell is optimized for write operations and the other port of the memory cell is optimized for read operations, the cell does not require multiple wordline voltages for each port.
摘要:
An asynchronous flag generator for generating an asynchronous flag having a minimum defined active pulse length. The asynchronous flag generator comprises an arbitrary length flag generator for generating an arbitrary length status flag signal from at least two asynchronous signals, one being a set flag signal and the other being a clear flag signal. A minimum pulse generator for generating a minimum pulse having a predefined pulse length upon initiation of the set flag signal. Combinational logic combines the arbitrary length status flag with the minimum pulse to generate an asynchronous status flag with a defined minimum active pulse length.
摘要:
In a single ended simplex dual port memory cell, one port of the memory cell is dedicated for writing operations and the other port of the memory cell is dedicated for reading operations. A bit of data received from the first port can be stored in the memory cell. The second port can detect the memory cell contents substantially simultaneously as the memory cell is storing a bit of data from the first port. Each port is optimized for its respective dedicated operation. In other words, one port is optimized for write operations and the other port is optimized for read operations. Because one port of the memory cell is optimized for write operations and the other port of the memory cell is optimized for read operations, the cell does not require multiple wordline voltages for each port.
摘要:
According to one embodiment, a multiple signal detect circuit (100) can include a detect node (102) and a reference node (104). The potential of the detect node (102) can be discharged (or charged) at a rate that depends upon the number of active input signals (M1 to Mn). The potential of the reference node (104) can be discharged (or charged) at a reference rate. The reference rate can be greater than the rate at which the detect node (102) is discharged (or charged) when one input signal is activated, and less than the rate at which the detect node (102) is discharged (or charged) when two input signals are activated. A differential voltage between the detect node (102) and reference node (104) can be amplified by an amplifier (110).
摘要:
A method is described for accessing data in a memory that has a first memory plane and a second memory plane. The method includes the step of sending a first plurality of data from the first memory plane to a data port. A second plurality of data from the second memory plane is pre-fetched only while the first plurality of data is sent from the first memory plane. The pre-fetching is performed a first plurality of clock cycles before the second plurality of data is sent to the data port.
摘要:
According to one embodiment, a content addressable memory (CAM) (100) can include a number of CAM entries (102-0 to 102-n) and corresponding status stores (106-0 and 106-n). Match indications from the CAM entries (102-0 to 102-n) and status information from status stores (106-0 and 106-n) can be supplied to a switching circuit (108). Status information can indicate if an entry stores valid or invalid data. In one mode of operation, the switching circuit (108) can provide match indication values on a number of switch outputs (SW0 to SWn). In another mode of operation, the switching circuit (108) can provide status information on a number of switch outputs (SW0 to SWn).
摘要:
According to one embodiment a content addressable memory (CAM) (100) can segment comparand values and data values into portions. Comparand value portions are compared with corresponding data value portions in sequential compare operations. Sequential compare operations can distribute current peaks over two or more compare operations, thereby reducing peak current transients.