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Altera_Forum
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13 years ago

about vhdl code for cic interpolation filter

i am attaching one pdf file based on cic filter.In the bitgrowth section the author has mentioned about the increase in the bits at the output stage .Suppose if i am writing a vhdl code for cic inter...
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Altera_Forum
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13 years ago

according to given equation :for decimator, last comb output bits = 9 * log2(8*1) + 23 = 50 bits

and it says, the same should be used at each comb or integrator stage. Leave truncation to final output.

for interpolator:

last stage = 23 + 9 -1 = 31 bits

and stage before last requires 23+8-1 = 30 bits and so on