A Cascaded Integrator Comb (CIC) filter is a special class of linear phase, Finite Impulse Response (FIR) filter as they do not require multipliers and use a limited amount of storage, thus CIC filters are more efficient than conventional FIR filters, especially in fixed-point applications.

The CIC filters can be used in multirate systems with large sampling frequency conversion factors, such as Digital Downconverters (DDC) and Digital Upconverters (DUC) in communication systems.