Power-aware RAM mapping for FPGA embedded memory blocks

ABSTRACT

Embedded memory blocks are important resources in contemporary FPGA devices. When targeting FPGAs, application designers often specify high-level memory functions which exhibit a range of sizes and control structures. These logical memories must be mapped to FPGA embedded memory resources such that physical design objectives are met. In this work a set of power-aware logical-to-physical RAM mapping algorithms are described which convert user-defined memory specifications to on-chip FPGA memory block resources. These algorithms minimize RAM dynamic power by evaluating a range of possible embedded memory block mappings and selecting the most power-efficient choice. Our automated approach has been integrated into a commercial FPGA compiler and tested with 40 large FPGA benchmarks. Through experimentation, we show that, on average, embedded memory dynamic power can be reduced by 21% and overall core dynamic power can be reduced by 7% with a minimal loss (1%) in design performance.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids

General Terms:
Algorithms

Keywords:
FPGA, dynamic power, embedded memory block