A new Configurable Decimation Filter using Pascal-s Triangle Theorem

This paper presents a new configurable decimation filter for sigma-delta modulators. The filter employs the Pascal-s triangle-s theorem for building the coefficients of non-recursive decimation filters. The filter can be connected to the back-end of various modulators with different output accuracy. In this work two methods are shown and then compared from area occupation viewpoint. First method uses the memory and the second one employs Pascal-s triangle-s method, aiming to reduce required gates. XILINX ISE v10 is used for implementation and confirmation the filter.

Authors:

• A. Chahardah Cherik
• E. Farshidi

Keywords:

• Decimation filter
• sigma delta
• Pascal's triangle'stheorem
• memory

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