Valid Logic Systems

Valid Logic Systems was one of the first commercial electronic design automation (EDA) companies. It was founded in the early 1980s, along with Daisy Systems Corporation and Mentor Graphics, collectively known as DMV.

Initially, Valid built both hardware and software, for schematic capture, logic simulation, static timing analysis, and packaging. Much of the initial software base derived from SCALD ("Structured Computer-Aided Logic Design"), a set of tools developed to support the design of the S-1 supercomputer at Lawrence Livermore National Laboratories. Later, Valid expanded into IC design tools and into printed circuit board layout.

At first, Valid ran schematic capture on a proprietary UNIX workstation, the SCALDSystem, with static timing analysis, simulation, and packaging running on a VAX or IBM-compatible mainframe. Within a few years, the (still proprietary) workstations were powerful enough to run all of the software. However, by the mid-1980s, general purpose workstations were powerful enough, significantly cheaper, and had given rise to a significant sector of the software industry, making them a better value on several counts. Companies such as Mentor Graphics and Cadence Design Systems took this path, and sold software only to run on standard workstations. However, the president of Valid, Jerry A. Anderson, felt that Wall Street would never adequately value a company that did not produce hardware, and insisted that the company's products continue to be bundled.^{[citation needed]} Eventually he was over-ruled by the board, but by then, considerable time had been lost to competitors.^{[citation needed]} By 1990, almost all Valid software was running on general purpose workstations, primarily those from Sun Microsystems.

The engineering founders of Valid were L. Curtis Widdoes, Tom McWilliams and Jeff Rubin, all of whom had worked on the S-1 supercomputer project at Livermore Labs.

Valid acquired several companies such as Telesis (PCB layout), Analog Design Tools, and Calma (IC layout). In turn, Valid was acquired by Cadence Design Systems in the early 90s.