Other

Yoji Kajitani

Hiroshi Murata

Shigetoshi Nakatake

Kunihiro Fujiyoshi

Atsushi Takahashi

Takuya Yasui

Masahiko Toyonaga

Keiichi Kurokawa

Based on the arrangement of a plurality of synchronous devices in an integrated circuit or on timing constraints, a group of discrete clock delay values composed of a finite number of discrete values to be allocated as respective clock delay values to the individual synchronous devices is determined. Then, the clock delay value selected from the group of discrete clock delay values is allocated as a selected clock delay value to each of the synchronous devices, while the operation of the integrated circuit is ensured. Thereafter, a clock circuit for supplying a clock signal to each of the synchronous devices in accordance with the selected clock delay value is designed.

Clock circuit and method of designing the same

Method of placing and extracting raw materials or modules in such a way that a minimum area capable of accommodating the modules can be systematically searched for. The placement of the modules is started with drawing rightwardly upward oblique lines and rightwardly downward oblique lines. The number of the oblique lines of each kind is equal to the number of the modules. The modules are placed at the intersections of the oblique lines such that only one module is placed on each one of the oblique lines. Those modules which are located to the right of an arbitrary module are defined to be located on the right side. In this way, vertical or horizontal positional relations among all the modules are determined. Then, the left sides of those modules which have no other modules on their left sides are placed on a vertical baseline. The lower sides of those modules which have no other modules on their lower sides are placed on a horizontal baseline. The modules other than the modules existing on the vertical baseline are brought close to the left side without overlapping other modules. As a result, the modules are packed in on the left side. Similarly, the modules other than the modules existing on the horizontal baseline are brought close to the lower side without overlapping other modules. As a result, the modules are packed in on the lower side.

Method of placing and extracting modules

Method of placing and extracting modules in such a way that a minimum area capable of accommodating the modules can be systematically searched for. The placement of the modules is started with drawing a grid having partitions or rooms greater in number than the modules. The grid is drawn by horizontal and vertical lines. Each horizontal line extends across two horizontally adjacent rooms. Each vertical line extends across two vertically adjacent rooms. Then, rectangular modules are arranged in the drawn rooms. Thereafter, the vertical lines are shrunk so that the horizontal lines are brought close to the top or bottom side of the grid while maintaining the vertical lengths of the modules inside the rooms. Finally, the horizontal lines are shrunk so that the vertical lines are brought close to the left or right side of the grid while maintaining the horizontal lengths of the modules inside the rooms.

Growing community of inventors

Yokohama-shi, Kanagawa-ken, Japan

Yoji Kajitani