A Dynamic Random Access Memory (DRAM) performs read, write, and refresh operations. The DRAM includes a plurality of sub-arrays, each having a plurality of memory cells, each of which is coupled with a complementary bit line pair and a word line. The DRAM further includes a word line enable device for asserting a selected one of the word lines and a column select device for asserting a selected one of the bit line pairs. A timing circuit is provided for controlling the word line enable device, the column select device, and the read, write, and refresh operations in response to a word line timing pulse. The read, write, and refresh operation are performed in the same amount of time.

High speed DRAM architecture with uniform access latency

A synchronous burst-access memory latches a row address strobe signal, a column address strobe signal, and address signals in synchronization with a clock signal. Data are stored in rows and columns in a memory cell array. Data in a selected row are input and output in serial bursts in synchronization with the clock signal, starting from a selected column. The row and initial column address are provided as external inputs; subsequent column addresses are generated by an internal address counting circuit. A word-line driving circuit for a synchronous memory uses transparent latches to latch the row address strobe signal and address signals, enabling row address decoding to be completed prior to synchronization with the clock signal.

Synchronous burst-access memory

A data processing system having a bus master and a memory which is capable of transferring operands in bursts of m in response to a burst request signal provided by the bus master, the operands being clustered modulo m about a selected access address provided by the bus master, where m is two (2) to the n power, n being an integer and characteristic of the memory. The bus master is adapted to automatically increment, modulo m, a selected set n of the bits of the access address as each operand in the burst is transferred, provided that the memory has indicated that the burst can be continued and less than m operands have been transferred.

Bus master having burst transfer mode

An address counter (2) counts the clock pulses sequentially to provide a count value as an address signal to a coincidence detecting circuit (3) and decoder (4). The coincidence detecting circuit (3) compares delay data applied from a delay data generating circuit (8) with the address signal and applies a reset signal to the address counter (2) when they coincide with each other. The address counter (2) repeats sequentially the above-mentioned operation in response to the reset signal after the count of address is reset to a predetermined value. The decoder (4) specifies a memory cell comprised in a memory device for performing a reading and writing operation in response to the address signal. The data output circuit (6) and the data input circuit (5) perform the reading and writing operation sequentially to the specified memory cell in response to the control signal outputted from the control circuit (7). As a result, the input data previously written is read and outputted with a delay. Therefore, a delayed input data can be obtained as an output data.

Variable delay circuit for delaying input data

A dual port digital memory system, which includes integral memory sequencing circuitry (22), is controlled by a bit-serial address and control signal (SAD). The address and control signal, which includes a data read address, a data write address and a control value, is serially loaded into a shift register (10). The address sequencing circuitry loads the read and write address values into integral read (24) and write (26) address registers and, based on the control value, initiates respective read and/or write operations.

Dual port video memory system having a bit-serial address input port

Dual port memory which enables consecutive access operations from an arbitrary address. The memory includes a memory array, a random access peripheral circuit for effecting random access to the array, a counter, a setting circuit for setting the counting state of the counter at an optional value, a selection circuit for consecutively selecting the array in response to the output of the counter, and a control circuit for advancing the state of the counter in response to a shift pulse.

Dual port memory circuit

A memory device operable at high-speed and with low power consumption is disclosed. The device in which row address information and column address information are incorporated in synchronism with a row strobe signal and a column strobe signal, respectively, and refresh is effected in response to a row address, comprises a plurality of groups of selection gates for selectively supplying the incorporated column address information to a part of a plurality of column address decoders.

Shoji Ishimoto

Papers

Dual port memory circuit

Semiconductor memory device having improved column selection structure