A Novel GALS Single-Track Protocol Asynchronous Communication Circuits

A novel GALS (globally asynchronous locally synchronous) asynchronous communication circuit which adopts the single-track handshake protocol is proposed. The circuit can complete data transmissions without acknowledgement signals. The backward transition of the circuit becomes delay-insensitive by adding an NCL (null convention logic) threshold gate in the RTZ (return to zero) process. The circuit has a forward transition delay less than 2 gate delays which is better than STFB (single-track full buffer) circuit. Simulations of function and performance of the circuit under different fabrication variations are implemented based on 0.18 mum CMOS technology. This circuit can work up to 2.56 GHz under five stages in series. The average power consumption of the circuit is only 5.869 mW. Its advantages of delay-insensitive and high-speed make it a viable option for high-speed on-chip data transmission applications of GALS.