Renesas Technology Corp.

Hitachi Ulsi Systems Co., Ltd.

Yoshio Takazawa

Toshio Yamada

Takeo Kanai

Shinichi Ozawa

Toshihiro Araki

Minoru Katoh

Koudou Yamauchi

Kazumasa Yanagisawa

Takashi Hayasaka

There are provided a plurality of bridge circuits which convert the test data information from a common test bus connected to a plurality of memories of different access data widths and address decode logics to the inherent access data widths of each memory and also convert the test address information from the common test bus to the inherent bit format of each memory to supply the result to the corresponding memory. The test address information is supplied in parallel from the common test bus to a plurality of memories to realize the parallel tests. Accordingly, the test data information can be supplied in parallel to a plurality of memories of different data widths and the address scan direction in the respective memories for the test address information can be uniformed to the particular direction depending on the inherent bit format. Thereby, the memory test efficiency by the match pattern for a plurality of on-chip memories can be improved.

Semiconductor integrated circuit and testing method thereof

A semiconductor integrated circuit has a memory which can enter active state or standby state, and the memory has voltage generation circuits for bit lines and source lines with which memory cells are connected. The voltage generation circuits make the potential of the bit lines and the potential of the source lines equal to each other in response to an instruction to transition from active state to standby state. The voltage generation circuits produce a potential difference between the bit lines and the source lines in response to an instruction to transition from standby state to active state. In standby state, the potential of the bit lines and that of the source lines are equal to each other. Therefore, sub-threshold leakage does not occur between the source and drain of each memory cell. In active state, the source line potential is not varied.

Semiconductor integrated circuit and IC card

Growing community of inventors

Kodaira, Japan

Yoshio Takazawa