This paper describes the design of a 256 x 256 port full crossbar switch for use in multiprocessor and telecommunications applications. The switch has a 50 Mbyte/sec bandwidth per port and a low message latency. Distributed arbitration is provided for output port contention. High packaging density, high speed, and I/O minimization are achieved through the use of a large area, defect-tolerant monolithic implementation in a 0.8 micron CMOS technology. The number of spare rows and columns in the switch matrix was determined by a detailed yield analysis.
