Patent Number: 6,297,675

Title: Semiconductor integrated circuit and semiconductor integrated circuit system having serially interconnectable data buses

Abstract: A data line pair and a strobe line pair are provided between first and second chips to exchange data therebetween. The first chip includes an output circuit and a controller for controlling the output circuit. The second chip includes an input circuit. For example, the output circuit supplies a direct current from a power supply to one of the data lines. Then, the input circuit feeds back the received current to the output circuit through a pair of terminal resistors and the other data line. Subsequently, the output circuit supplies the fed back direct current to one of the strobe lines. In response, the input circuit feeds back the received current again to the output circuit through another pair of terminal resistors and the other strobe line. And then the fed back current is drained to the ground. Thus, compared to driving the data and strobe line pairs separately with the same amount of current supplied, the current dissipation can be halved. In this manner, the present invention is applicable to reduction of current dissipation when data should be transmitted at high speeds through multiple data bus pairs that are driven with a current supplied.

Inventors: Akamatsu; Hironori (Osaka, JP), Terada; Yutaka (Osaka, JP), Hirata; Takashi (Osaka, JP), Arima; Yukio (Osaka, JP), Takahashi; Satoshi (Osaka, JP), Yoshida; Tadahiro (Osaka, JP), Komatsu; Yoshihide (Osaka, JP), Yamauchi; Hiroyuki (Osaka, JP)

Assignee: Matsushita Electric Industrial Co., Ltd.

International Classification: H03K 19/0185 (20060101); H03B 001/00 ()

Expiration Date: 10/02/2018