High-performance asynchronous pipeline circuits

This paper presents design and simulation results of two high-performance asynchronous pipeline circuits. The first circuit is a two-phase micropipeline but uses pseudo-static Svensson-style double edge-triggered D-flip-flops (DETDFF) for data storage in place of traditional transmission gate latches or Sutherland´s capture-pass latches. The second circuit is a four-phase micropipeline with burst-mode control circuits. We compare our DETDFF and four-phase implementations of a FIFO buffer with the current state-of-the-art micropipeline implementation using four-phase controllers designed by Day and Woods for the AMULET-2 processor. We implemented Day and Woods´s design and both of our designs in the MOSIS 1.2 μm CMOS process and simulated them with a 4.6 V power supply and at 100°C. Our SPICE simulations show that our DETDFF and four-phase designs have 70% and 30% higher throughput respectively than Day and Woods´s design. This higher throughput for the DETDFF design is due to latching the data on both edges of the latch control, removing the need of a reset phase and simplifying the control structures. Our four-phase design, on the other hand, has higher throughput because of the simplified control structures and the removal of the latch enable buffers from the critical path. The four-phase design, though not quite as fast as the DETDFF design, requires much smaller area for data storage