Printed circuit boards (PCBs) are used to connect electronics using conductive pathways laminated onto non-conductive material. They are reliable and cheap when mass produced, as their production can be completely automated. Electronic design automation (EDA) is the name used to describe software intended to aid in the imaging and design of PCBs.
History
Before the mid-1970s, circuits were manually designed and manufactured. Automated design got underway when the first placement and routing tools were invented. In 1980, the advent of very large scale integration (VLSI) systems methodology, which entailed software-aided chip modeling and design, resulted in a dramatic increase in the complexity of verification and design. While the earliest EDA tools were developed by universities, in 1981 EDA became an industry unto itself. In 1986, Verilog, a complex design language, was introduced. It is still in use today.
Schematic Capture
Schematic capture, or schematic entry, refers to the creation of an electronic circuit design, accomplished interactively with computer-aided design (CAD) software, usually after being hand-drawn on paper. As complex as today's circuit boards are, the complexity of modern schematic capture software means this task is easier today than it was in the past. After circuit design is completed, most EDA tools allow functional simulation as well. Laminography tools use three-dimensional (3-D) X-ray imaging for PCB failure analysis, and such applications allow for effective reverse engineering of semiconductor circuits.
Examples
There are many brands of PCB imaging software available, both open source and proprietary, and often directly linked to a PCB manufacturer. KiCad is very popular because of its versatility and its availability on all major operating systems. Open Schematic Capture is a Java-based schematic capture and net list program. Verilator is considered the fastest, free Verilog hardware description language (HDL) simulation software available. Cadence OrCAD is known for its robustness across the entire design process.
