Cascaded Integrator-Comb (CIC) filters, also known as Hogenauer filters, are used to achieve arbitrary and large sample rate changes in digital systems. These filters are used as decimation or interpolation filters and can be efficiently implemented without multipliers, utilizing only adders and subtractors.
A CIC filter is typically used in applications where the system sample rate is much larger than the bandwidth occupied by the signal. They are commonly used to build Digital Down Converters (DDCs) and Digital Up Converters (DUCs). Some applications that use the CIC filter include software designed radios, cable modems, satellite receivers, 3G base stations, and radar systems.
Lattice provides a widely parameterizable CIC filter that supports multiple channels with run-time programmable rates and differential delay parameters.