An efficient data transmission interface for VLSI systems using code-division multiple access technique

An efficient data transmission bus interface for VLSI systems is proposed. Unlike its predecessors, the proposed MB-CDMA (Multiple-Bit Code Division Multiple Access) bus is capable of transmitting multiple-bit data at each cycle. All signals transmitted through the MB-CDMA bus are modulated using Pseudo-Noise sequence codes, enabling parallel transmissions using the same bus line. Due to its narrow band rejection features, the voltage swing at the bus can be reduced to tens of milli-volts to achieve low power consumption. The MB-CDMA interface had been successfully implemented with a 0.6µm CMOS process.