Cadence is commercial software. This post is for informational and educational purposes regarding the official download process for licensed users. Unauthorized distribution or use of cracked software is illegal and violates Cadence’s intellectual property rights. The Complete Guide to Downloading Cadence OrCAD and Allegro 17.4 If you are a PCB designer, hardware engineer, or electronics student, you know that Cadence OrCAD (for schematic capture) and Allegro (for PCB layout) are the industry gold standard. Version 17.4 remains one of the most stable and widely used releases.