Hello!

While working with a MAC-FIR I came across an equation in Xilinx' DSP-book

On page 65 equation 4.4 for the generic saturation level says Output width = ceil(log2(2^(b-1)*2^(c-1)*N))+1 Where b/c are the numbers of data/coefficient bits and N is the filter length.

This formula is, apart from a missing parenthesis, ok, but the next one for known coefficients says Output width = ceil(log2(2^(b-1)***abs(sum(coef))***N))+1

Again missing right parenthesis and the N is in my eyes wrong, because it is already included in the sum of coefficients. Could anyone approve this? I have to cite this paper in a thesis in lack of another source for this equation (though it seems to be obvious, but I have to be sure).

Thanks, Holger