Digital dividers are integrated circuits (ICs) that divide the frequency of an input signal by a division ratio. There are two basic types of digital dividers: fixed dividers and programmable dividers. Fixed dividers have a division ratio that users cannot change. By contrast, programmable dividers can be programmed to use any division ratio up to a maximum limit. Both types of digital dividers are used in a variety of electronics applications as frequency synthesizers. In phased locked loops (PLLs), digital dividers receive input signals from voltage-controlled oscillators, divide signals by a division ratio, and send outputs to a phase comparator. For example, a divide-by-two circuit provides one output for every two inputs. For non-truncated dividers, the number of bits or stages is 2n, where n is the number of flip-flops (bits) in the divider.
