Title |
Low-power Decimation Filter Structure for Sigma Delta A/D Converters in Cardiac Applications |
Keywords |
시그마 델타 변환기 ; 데시메이션 필터 ; 심장박동기 CSD ; Common Sub-expression Sharing |
Abstract |
The low-power design of the A/D converter is indispensable to achieve the compact bio-signal measuring device with long battery duration. In this paper, new decimation filter structure is proposed for the low-power design of the Sigma-Delta A/D converter in the bio-instruments. The proposed filter is based on the non-recursive structure of the CIC (Cascaded Integrator Comb) decimation filter in the Sigma-Delta A/D converter. By combining the CSD (Canonic Signed Digit) structure with common sub-expression sharing technique, the proposed decimation filter structure can significantly reduce the number of adders for implementation. For the fixed decimation factor of 16, the 15% of power consumption saving is achieved in the proposed structure in comparison with that of the conventional polyphase CIC filter. |