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FIR Analog Approximations

FilterSolutions supports FIR approximations of all supported analog filters. This is advantageous when only a limited number of bits of precision are available to create the desired IIR filter.  IIR filters, especially those of Standard Form implementation, are more susceptible to finite precision error than FIR filters.  IIR filters may become unstable if insufficient precision is available to build the desired filter.  

FIR filters never become unstable.  FIR filter coefficients are always between +1 and –1, which allows for greater ease when computing with fixed point arithmetic.

The FIR filter is created by directly encoding the sampled analog filter impulse response into the FIR Z-Transform. FilterSolutions allows the entry of the desired sample rate, and FIR tap number, to create an FIR approximation.