Fujitsu Corporation

Spansion Llc.

Motoko Tanishima

Mitsuharu Sakakibara

Hiroshi Mawatari

Based on a continuous erase start signal outputted, in response to an inputted continuous erase command, from a continuous erase control circuit, a shift circuit outputs a control signal for giving instructions to execute respective data erase operation to a plurality of non-volatile memory circuits sequentially, and when the data erase operation in all of the non-volatile memory circuits has been completed, the shift circuit outputs a continuous erase completion signal. Thereby, the data erase operation in all of the non-volatile memory circuits built in one chip can be continuously executed by one continuous erase command as is also the case where a single non-volatile memory circuit is built in.

Semiconductor memory device having non-volatile memory circuits in single chip

Semiconductor memory device

A memory circuit has a regular memory cell array; a redundant memory cell array that can replace a failed portion in the regular memory cell array; a redundant replacement memory for storing data on the failed portion in the regular memory cell array; and a pre-charge circuit disposed in the regular memory cell array, depending on the data on the failed portion, the failed portion in the regular memory cell array is replaced with the redundant memory cell array, whilst a pre-charge path is closed which leads to the pre-charge circuit corresponding to the failed portion. This enables a common redundant replacement memory to effect a relief of the failed portion and shutoff of the pre-charge current to the failed portion.

Memory circuit with redundant memory cell array allowing simplified shipment tests and reduced power consumptions

An Nch-Tr having a gate connected to an input terminal and an Nch-Tr having a gate connected to an output signal voltage supply terminal through a Pch-Tr are connected to an output terminal for outputting an output signal carrying a second voltage level. In changing the output signal from a high level to a low level in accordance with a change of an input signal carrying a first voltage level, both the Nch-Trs are initially turned ON to lower the voltage of the output signal, and then the Nch-Tr having its gate connected to the output signal voltage supply terminal through the Pch-Tr is brought into a high ON state (a state of higher driving power) to turn the voltage of the output signal to the low level, so that the output signal can be changed quickly by a simple circuit configuration.

Growing community of inventors

Kawasaki, Japan

Motoko Tanishima