A Spurious-Power Suppression Technique for Multimedia/DSP Applications

This paper presents the design exploration and applications of a spurious-power suppression technique (SPST) which can dramatically reduce the power dissipation of combinational VLSI designs for multimedia/DSP purposes. The proposed SPST separates the target designs into two parts, i.e., the most significant part and least significant part (MSP and LSP), and turns off the MSP when it does not affect the computation results to save power. Furthermore, this paper proposes an original glitch-diminishing technique to filter out useless switching power by asserting the data signals after the data transient period. This paper adopts two multimedia/DSP design examples, i.e., a multitransform design for H.264 and a versatile multimedia functional unit (VMFU), to evaluate the proposed SPST. These two design examples have quite different hardware configurations, thus, the realization issues of the SPST on every design also remarkably differ from each other. The multitransform design can compute three transforms which are required in H.264 encoding while the VMFU possesses six commonly used multimedia/DSP functions, namely, addition, subtraction, multiplication, MAC, interpolation, and sum-of-absolute-difference. After optimizing the design elaborately, we find that the proposed SPST can, respectively, save 27% and 24% power dissipation on average of the H.264 multitransform design and the VMFU at the expense of less than 20% area augmentation.