Printed Circuit Board for Apple Computer

The empty circuit board.

The Challenge: Create a printed circuit board that can easily and arbitrarily route 30 output lines from a laptop keyboard matrix to 33 inputs on a controller board.

Technical Approach: Using Unigraphics for the mechanical layout and Cadence for the circuit design, I created a 30x33 grid woven together by 990 DIP switches. I then worked closely with a board layout engineer to route a PCB, which was professionally fabricated and stuffed. The task of designing within a company gave me experience in requisitioning parts and dealing with nuances like ROHS compliance.

Selected Design Features: The shear number of switches necessitated a PCB over 14" long and 10" wide. To achieve the required mechanical strength across such a large area, a thickness of about 0.1" was used. In addition to 99 DIP packages with 10 switches each, 14 headers interfaced the board to a variety of keyboard matrices and controller boards. The entire design was completed over the course of several weeks.