Abstract: A novel switchable unit-delay has been developed for the efficient implementation of programmable digital finite impulse response filters and correlators. A p-tap consisting of this novel switchable unit-delay and a two-non-zero-digit partial product generator and adder have been implemented. The combination of several p-taps, made possible by the switchable unit-delay, allows for the efficient implementation of coefficients with more than two non-zero digits. In a straightforward implementation of a programmable finite impulse response filter, many tap "multipliers" would significantly waste valuable computational resources since all filter taps would need to accommodate "difficult" coefficient values (i.e., many non-zero digits), while for any specific transfer function, most filter taps would not require such extreme capabilities.