Asynchronous circuit design using new high speed NCL gates

The delay-insensitive Null Convention Logic (NCL) as one of innovative asynchronous logic design methodologies has many advantages of inherent robustness, power consumption, and easy design reuses. However, transistor-level topologies of conventional NCL gates have weakness of logic speed, area overhead or wire complexity. Therefore, this paper proposes a new NCL gates designed at transistor level for high-speed, low area overhead. A 4×4 multiplier using the proposed NCL gates has been compared to the multiplier using conventional NCL gates in terms of delay, area and energy consumption.