FPGA Design for Timing Yield Under Process Variations

Yield loss due to timing failures results in diminished returns for field-programmable gate arrays (FPGAs), and is aggravated under increased process variations in scaled technologies. The uncertainty in the critical delay of a circuit under process variations exists because the delay of each logic element in the circuit is no longer deterministic. Traditionally, FPGAs have been designed to manage process variations through speed binning, which works well for inter-die variations, but not for intra-die variations resulting in reduced timing yield for FPGAs. FPGAs present a unique challenge because of their programmability and unknown end user application. In this paper, a novel architecture and computer-aided design co-design technique is proposed to improve the timing yield. Experimental results indicate that the use of proposed design technique can achieve timing yield improvement of up to 68%.