A FPGA prototype design emphasis on low power technique

Abstract

In this paper, we propose a fully-functional Nanometer FPGA prototype chip. Compared to traditional single supply voltage, single threshold voltage design, we explore low power nanometer FPGA design challenges with Multi-Vt, Static Voltage Scaling and sleep mode technique. Compared to Dynamic Voltage Scaling (DVS), we make a table of Voltage-Delay parameter pairs under different voltage conditions so that timing information can be calculated by a Static Timing Analysis (STA) tool. Thus a lowest supply power is chosen among all results which meet the timing requirements. This approach would simplify the hardware design since we don't need a complex workload detection circuit compared to DVS system. By separating supply voltages, we can directly shutdown power supply of the unused circuits. Compared to inserting sleep transistor in pull-up or pull-down networks, we can eliminate the speed penalty cased by the additional sleep transistor. We implement a tile-based heterogeneous architecture with island style routing and embedded specific blocks such as DSP and memory. The array size is 64×31 (Row×Col) including 64×24 CLBs. The final design is fabricated using a 1P10M 65-nm bulk CMOS process. Test results show a 53% reduction in static power compared to a commercial FPGA device which is also fabricated in 65nm process and has a similar array size.