Claimed to be the industry’s first Personal Computer-based based printed circuit board design system that supports true surface mount technology design, Version 2.0 of P-CAD has been introduced by Personal CAD Systems Inc, San Jose, California. Surface mounting of components enables them to be placed closer together, packing more circuits onto a given area of board, and once the capital equipment is in place, substantially reduces manufacturing costs. It is a key feature of the IBM Personal System/2 machines. As well as surface mount support, the new release includes functional and performance enhancements to its automated layout tools, and improved data handling algorithms to allow the design of larger printed circuit boards. Available next month, the new version, with manual layout and design, data extraction, design rule checking, and hard copy support, will cost from $6,500. Surface mount technology features include single layer pins, interstitial or buried vias, and components mounted on both sides of the board. A layer mapping scheme used during part entry allows a single library part to be placed on either side of the board with no need to have two versions of the same part. The TTL, CMOS, Discrete and Linear libraries have been updated to include surface mount parts. The PC-Route and PC-Place automated tools now incorporate surface mount, and increased board size. Improved algorithms allow better overall routing quality and speed while optional 45 degree bevelling of all 90 degree angles for manufacturability has been added.
Iterative improvement
PC-Place also includes iterative improvement of initial placement through component and gate swapping. The board design size limitations of the earlier versions of PC-Cards PC-Place and PC-Route modules have been removed by using new data access methods. The larger database size for these programs expands support to 500 components, 8,000 pins and 1,000 nets. Improvements to PC-Caps and PC-Cards interactive editors include: surface mount features added; block save and load capabilities for quick cut and paste of areas of a database that may be common to several designs; automatic bus wire creation in PC-Caps; On-screen pan bars for quick database viewing; symbol editor enhancements to facilitate creation and modification of schematic and printed circuit board symbols; orthogonal rubber banding to aid in moving components in PC-Caps; electrically connected, filled polygons for power and ground planes and other applications in PC-Cards; the ability to define circuit board databases in Imperial or metric units; alphanumeric pin numbers to support pin grid arrays and connectors; PC-Plots graphical interface to Interleaf’s publishing system for design documentation.The system shell supports menus designed to be easy to understand to facilitate use of the system by the novice user. It is organised to reflect the logical progression of tasks in the design process. Also included is Novell/3Com Ethernet network support, a netlist comparison program, engineering rules check program, ASCII netlist input to PC-Cards and Hewlett-Packard LaserJet support.
