摘要:
A semiconductor memory device includes a plurality of memory blocks, i main row or column select lines extending over the plurality of memory blocks, and a decoder for selecting one of the main row or column select lines in accordance with an applied address signal. The decoder includes i outputs. Each of the memory blocks includes a plurality of memory cells arranged in rows and columns and at least (i+1) sub row or column select lines each for selecting one row or one column of memory cells. A shift redundancy circuit is provided for each of the memory blocks, for connecting the main row or column select line and the sub row or column select line. The shift redundancy circuit includes a switch circuit for connecting one main row or column select line to one of the plurality of adjacent sub row or column select lines, and a circuit for setting a connection path of the switch circuit. The shift redundancy circuit connects successively adjacent sub row or column select lines to main row or column select lines in one to one correspondence except a defective sub row or column select line associated with a defective bit.
摘要:
A semiconductor device having amplifying circuits provided near corresponding bonding pads receiving external signals, and positioned between the bonding pads and internal circuits to which such external signals are to be applied. The device includes a control signal generating circuit for the amplifying circuits which is not provided in conventional semiconductor devices. In response to external control signals, the control signal generating circuit generates internal control signals for controlling electric paths between a power supply and ground in the amplifying circuits. During the standby period of the semiconductor device, the paths between the power supply and ground are cut regardless of the potential of the corresponding bonding pads, preventing flow of a through current.
摘要:
Column repairing circuits 7a, 7b for repairing a DRAM in which there are defective memory cells in two columns are disclosed. The connection state of switching elements or circuits 51-5n, 61-6n, 71-7 (n+1), 81-8 (n+1) is determined as illustrated by appropriately disconnecting fuses in fuse links provided respectively in circuits 7a, 7b. Accordingly, column selecting lines Y2a and Y (n+1) b in memory array blocks 891a, 891b are not activated. The two repairing circuits 7a, 7b are provided spaced apart from each other on a semiconductor substrate, so that excessive concentration of fuse elements and switching elements or circuits is prevented.
摘要:
A plurality of sub chips are formed on a chip. An input/output buffer region is arranged around the plurality of sub chips. Each sub chip includes a sub chip control circuit region and a plurality of memory cell array blocks. Each memory cell array block includes a memory cell array region, a row decoder and control circuit region, a sense amplifier region and an input/output latch region.
摘要:
A semiconductor memory device includes a memory array. The bit line pairs of the odd number order in the memory array belong to a first group, and the bit line pairs of the even number order belong to a second group. A first amplifier is connected to each bit line pair. Corresponding to the first group, write buses read buses and a read/test circuit are provided. Corresponding to the second group, write buses read buses and a read/test circuit are provided. A column decoder selects a plurality of bit line pairs simultaneously at the time of testing. At the time of testing, each of the read/test circuits compares data read out from the plurality of bit line pairs belonging to the corresponding group with a given expected data for providing the comparison result.
摘要:
In a memory cell array, data lines are formed into a hierarchical arrangement of sub data lines provided for every block and a main data line common to each block, and a sub data line selected by a column address among sub data lines belonging a block which are simultaneously selected by a row address is connected to a bit line. Accordingly, the sub data line length is reduced, which reduces floating capacitance, reading and writing operations can be conducted at a high speed, and sub data lines can be selectively operated. In addition, power required for charging the sub data lines can be reduced, and entire power consumption by the semiconductor memory device can be reduced as well.
摘要:
In a general read out operation, data read out from a memory cell array is amplified by a preamplifier group. The amplified data is provided to a selector unit. The selector unit responds to a bit organization select signal to select data according to a predetermined bit configuration. The selected data is provided to a data bus. In a test mode, the selector unit responds to a test mode signal to provide a test result to a data bus corresponding to a predetermined bit organization. Therefore, only the required data bus is used according to the bit organization and the test mode.
摘要:
A dynamic random access memory that contains a memory cell array including a plurality of memory cells includes a pre-amplifier intended to amplify data which is read out from a memory cell accessed by an address signal; a main-amplifier intended to amplify the output of the pre-amplifier and output the amplified signal; and a driver circuit intended to output a driving signal for driving the main-amplifier, the driver circuit includes a first and a second transistor, wherein a drain of the first transistor is connected to a node corresponding to an output terminal of the driver circuit, with a source of the first transistor being earthed and with a gate thereof being connected to the drain of the second transistor, and wherein a gate of the second transistor is connected to the node with a source thereof being earthed.
摘要:
Read data supplied from one of a plurality of differential amplifier circuits is transmitted to a read data bus driver circuit via one of a plurality of CMOS transfer gates and a data latch circuit. The potential of read data bus pair is forcedly set to a low level in response to a control signal until the read data is transmitted to the read data bus driver circuit. Thereafter, the read data bus driver circuit drives the read data bus pair in accordance with the transmitted read data. Thereby, a speed of the address access operation can be increased without outputting invalid data.
摘要:
A variable delay line receives and delays a data strobe signal transferred from a data source side in synchronization with a transfer data by a predetermined period, and produces a delayed data strobe signal and the non-delayed data strobe signal to a detector. The detector determines that a preamble period ends and effective data is transferred, when the delayed data strobe signal is at the L level at the time of rising of the non-delayed data strobe signal from the L level to the H level. According to a result of detection, an interface circuit unit takes in the transfer data and initializes a take-in address. The data strobe signal changes to a high-impedance state when a postamble ends. An influence of a glitch noise is avoided upon this change of the data strobe signal, and the data transfer can be executed fast and accurately.