Kabushiki Kaisha Toshiba

Katsuhiro Seta

Hiroyuki Hara

Toshiyuki Furusawa

Masaaki Yamada

Takayasu Sakurai

Masataka Matsui

Takeshi Kitahara

Masahiro Kanazawa

Naoyuki Kawabe

Yoshinori Watanabe

Takayoshi Shimazawa

Takeshi Yoshimoto

Munehito Mushiga

An automatic circuit design apparatus includes a setting module configured to set an upper limit electric potential of a virtual ground line in a circuit to be designed, by use of a cell library for low-threshold cells, a cell library for high-threshold cells, and information of the circuit to be designed. A layout generator is configured to generate a layout based on the information, the cell library for low-threshold cells, and the cell library for high-threshold cells.

Automatic circuit design apparatus, method for automatically designing a circuit, and computer program product for executing an application for an automatic circuit design apparatus

Semiconductor integrated circuit

A first and second barrel shifters (BSA0 and BSA1) are connected directly without intervening any pipe-line register between the two, and a sense amplifier (R3A0) is provided at an output side of the second barrel register (BSA1). Further, the circuit patterns of the first and second barrel shifters are formed being overlapped with each other in such a way that the elements of one of the first and second barrel shifters are formed at the dead space of the other of the two barrel shifters to reduce the pattern area. In the shift circuit and the variable-length decoder, the data lines of the barrel shifters can be minimized in size and width.

Barrel shifter device and variable-length decoder

A tag section of a cache memory system comprises a memory for storing a plurality of first address data read out with a small amplitude (e.g., 0.2 Vpp), a circuit for comparing a plurality of second address data, input from the outside of the system, with the plurality of first address data, and providing comparison results with a second amplitude (e.g., 0.8 vpp), an OR logic circuit including a plurality of bipolar transistors having bases to which the comparison results are respectively supplied, collectors connected to a first voltage source, and emitters which are all connected to an emitter dot line, and a circuit for measuring the potential of the emitter dot line by using a reference voltage to determine that all the first and second data coincide with each other. Since a read operation with respect to each tag memory and most hit detecting operations are performed with small-amplitude signals of the ECL level, a high-speed operation can be performed.

Cache memory system

A cell library for a semiconductor integrated circuit design, comprises a CMOS cell comprising two power source wires and a CMOS circuit placed between the two power source wires at a predetermined distance, and a BiCMOS cell comprising two power source wires which are placed at a distance equal to the distance between the power source wires in the CMOS cell, a CMOS circuit placed between the two power source wires in the BiCMOS cell, and bipolar transistor circuits placed at both outsides of the two power source wires in the BiCMOS cell.

Cell library for semiconductor integrated circuit design

An input terminal IN is connected to the input of a CMOS inverter, and also to the gate of an N-channel MOS transistor N10. The output of the CMOS inverter is coupled to the base of an NPN transistor Q11 used for pulling up the output terminal OUT. The drain of the transistor N10 is connected to the input of a CMOS inverter. The output of the inverter is connected to the base of an NPN transistor Q12 used for pulling down the output terminal OUT. The emitter of the transistor Q11 and the collector of the transistor Q12 are connected to an output terminal OUT, which is coupled to the gate of a P-channel MOS transistor P12 and the gate of an N-channel MOS transistor N3. The drain of the transistor P12 is connected to the drain of the transistor N10. The drain of the transistor N13 is connected to the source of the transistor N10. The transistors N10, P12, and N13 constitute a circuit for controlling the CMOS inverter.

BiCMOS logic circuit

In a semiconductor memory device of a divided bit line system, read signals from memory cell blocks are sense-amplified together by a single differential bit line sense amplifier. The bit line sense amplifier includes a plurality of first transistors, the base electrodes of which are connected to local bit lines of the memory cell blocks, the emitter electrodes of which are commonly connected to corresponding main bit lines, and the collector electrodes of which are connected to a first power supply node, a second transistor, which forms a differential pair with each of the first transistors, the base electrode of which is applied with a reference bias potential, and the emitter electrode of which is connected to the main bit lines, a current source connected between the emitter electrode of the second transistor, and a second power supply node, and a load circuit connected between the collector electrode of the second transistor and the first power supply node. The main bit lines with a heavy load can be driven by the emitters having a large driving force, and the outputs from the memory cell blocks can be sensed without going through selectors, thus attaining high-speed read access.

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Tokyo, Japan

Katsuhiro Seta