US Patent 8378719 Programmable high-speed frequency divider

A programmable high-speed frequency divider architecture is provided to provide a substantially 50% duty cycle signal output regardless of whether the division ratio is odd or even. The programmable frequency divider circuit receives an input clock signal having a first period and outputs and output clock signal that has a second clock signal period that is a programmable multiple, A, of the first period. The frequency divider includes a shift register that receives the input clock signal and produces a first output signal. The frequency divider also includes a duty cycle compensation circuit that accepts the first output signal and produces an output clock signal that has a duty cycle that is substantially 50%.