Lecture2 - Primising low power solutions : Application Specific Instruction-set Processors
Custom ASIC solutions face several limitations such as lack of flexibility and high development costs. In contrast, general DSP-based solutions require large die size and high power consumption. Hence, system design methods have been changed to application-specific instruction-set processor (ASIP) based design compromising advantages of both ASIC (optimization) and DSP (flexibility). The talk presents three implemented ASIPs. Signal Processor for OFDM Communication Systems (SPOCS) is implemented for OFDM systems that require FFT, scrambling/descrambling, etc. SPOCS can dramatically reduce the number of cycles and memory access. The implemented SPOCS can meet various standards, such as WLAN, WiMAX, etc. Digital Audio Specific Instruction-set Processor (DASIP) implemented for high-quality audio algorithms employs the optimized instruction set and architecture for the Inverse Modified Discrete Cosine Transform (IMDCT), the dedicated Huffman accelerator, etc. Video Specific Instruction-set Processor (VSIP) implemented for H.264/AVC has a special instruction set for intra-prediction, integer transform, etc. and employs hardware accelerators for motion estimation/compensation and entropy coding. VSIP can give flexibility and low power consumption. These efficient ASIPs can significantly reduce the number of cycles and memory access and the computation complexity, and thus, they can dramatically save power consumption.