Abstract: One of the most important RF building blocks today is the frequency synthesizer, or more particularly the programmable frequency divider (divider). Such dividers preferably would support unlimited range with continuous division without incorrect divisions or loss of PLL lock. The inventors present multi-modulus dividers (MMDs) providing extended division range against the prior art and without incorrect divisions as the division ratio is switched back and forth across the boundary between two different ranges. Accordingly, the inventors present MMD frequency dividers without the drawbacks within the prior art.