Hitachi, Ltd.

Yasuhiro Fujimura

Keiichi Higeta

Shigeru Nakahara

Kenichi Osada

Masanao Yamaoka

Toshiro Takahashi

Akihisa Uchida

Kunihiko Yamaguchi

Takayuki Muranaka

Shunsuke Toyoshima

Isao Kimura

Takashi Muto

Tetsuya Fukuoka

Junji Baba

Minoru Motoyoshi

Sohei Omori

Koki Tsutsumida

Yuichi Ito

Etsuko Iwamoto

Etsuko Kawaguchi

Ryo Nishino

Objects of the invention are to minimize power consumption while maintaining the required information processing capabilities of an LSI chip by supplying multiple voltages to the LSI chip such that its circuit blocks receive necessary voltages and to prevent an increase in the chip area of the LSI chip and performance degradation of signal wires, which may result from the supply of the multiple voltages, by reducing the number of power supply wires. In an LSI chip to which two voltages are supplied, high voltage wires are more densely spaced than low voltage wires. By selectively applying voltages based on circuit block performance, it is possible to reduce power consumption while maintaining the amount of information processed by the LSI chip.

Semiconductor device and information processing apparatus using the same

A scan chain group structure in which a group of scan chains formed for each clock tree system in an LSI is subjected to a reconnection process so that the scan chain group is not present across a plurality of clock distribution regions obtained by dividing the clock-supplied region of the clock tree of one system and that the connection distance thereof in the distribution region becomes short, a test clock input mechanism in which test clocks to be input to the distribution regions are independent sub-clock phases, and an on/off mechanism of the clocks to be input to the distribution regions are realized. Further, the scan-in/out and scan test performed at the same time are limited in one region or between single regions, and tests in all regions and between all regions are carried out by a plurality of times of test steps.

Semiconductor integrated circuit device for scan testing

In a data transfer device which cancells an offset of a differential amplifier for amplifying a received signal and an offset caused by characteristics of a differential transmission line and selects optimum conditions such as pre-emphasis amount of an output pre-emphasis circuit, a first chip (transmission side LSI=transfer engine) and a second chip (reception side LSI=multiplexing engine) are connected to each other through differential transmission lineand a SerDes (serializer)and a SerDes (deserializer)are used to make signal transmission, so that optimum setting conditions of an offset amount of an offset cancellation circuit included in an input buffer amplifier and a pre-emphasis amount of pre-emphasis circuit included in an output buffer are decided in training using a training PRBS generatorand a training PRBS comparator

Data transfer device of serializer/deserializer system

Clock skew can be reduced by suppressing fluctuation in wiring leads between the final stage clock buffers and the clock distribution circuit for supplying the clock. In view of attaining such reduction of clock skew, an upstream of the clock distribution circuit is formed in an H tree structure and the final stage is formed in a local fishbone structure. A plurality of main clock lines connected to the final stage buffer include a first main clock line and a second main clock line. The number of cell arrangement allowable rows where a plurality of first flip-flops for receiving the clock from the first main clock line are located is different from the number of cell arrangement allowable rows where a plurality first flip-flops for receiving the clock from the second main clock line are located.

Semiconductor device

The invention provides a technique that enables a correct discrimination of reception data, when the supply voltage of a semiconductor integrated circuit having a simultaneous bi-directional interface is decreased. The data transmission system is provided with input circuits constituting a simultaneous bi-directional interface by the number of reference voltages used. Each of the input circuits is supplied with a fixed reference voltage, the input circuit supplied with a higher reference voltage employs a differential amplifier with n-channel MOSFETs served as input differential devices, and the input circuit supplied with a lower reference voltage employs a differential amplifier with p-channel MOSFETs served as input differential devices, in which selectors switch the outputs of the two differential amplifiers in correspondence with the output data of their own. Thus, the system attains the reception data.

Data transmission system

Read signals to be outputted in the unit of bits from a packaged RAM are received to produce complementary output signals, and these output signals and the non-inverted and inverted signals of expected values are individually inputted to two logic circuits, so that the outputs of the logic circuits are compared by a coincidence/incoincidence circuit to produce a decision output.

Semiconductor integrated circuit device

An integrated circuit including latch circuits disposed on the input and output sides of an object circuit the delay time of which is to be measured, respectively, and a variable delay circuit capable of arbitrarily delaying a timing signal supplied from outside or a timing signal generated inside the integrated circuit by an instruction from outside. The timing signal and a delay signal obtained by delaying the input signal by the variable delay circuit are supplied as clock signals to the latch circuits, and the signal passing through the variable delay circuit is fed back to the input side so as to constitute an oscillation circuit, the oscillation signal of which can be outputted to outside. A signal delayed by a desired time can be automatically generated inside the semiconductor integrated circuit on the basis of this timing signal.

Semiconductor integrated circuit device having circuit inspection

Growing community of inventors

Hamura, Japan

Yasuhiro Fujimura