FPGA Implementation of Power Aware FIR Filter Using Reduced Transition Pipelined Variable Precision Gating

Abstract

With the emergence of portable computing and communication system, power awareness is one of the major objectives of VLSI Design. This is its ability to scale power consumption based on the time-varying nature of inputs. Even though the system is not designed for being power aware, systems display variations in power consumption as conditions change. This implies, by the definition above, that all systems are naturally power aware to some extent. However, one would expect that some systems are more power aware than others. Equivalently, the system should be able to re designed to increase their power awareness. This research proposes a pipelined Variable precision gating scheme to improve the power awareness of the system. This research illustrates this technique by applying it to FPGA Implementation of multipliers and digital FIR filters. This proposed technique is to clock gating to registers in both data flow direction and vertical to data flow direction within the individual pipeline stage based on the input data precision. For signed multipliers using 2's complement representation, sign extension, which wastes power and causes longer delay, could be avoided by implementing this technique. Very little additional area is needed for this technique. The designed circuit is simulated, synthesized and implemented in Xilinx Spartan 3e FPGA. The Power is analyzed for the designed circuit and the power saving of 18 % obtained for the proposed FIR Filter with 3 % increase in area compared to the existing pipeline gating design