Design and Implementation of Programmable Divider for 2.4 GHz Frequency Synthesizer

A programmable divider of frequency synthesizer applied to the 802.11b protocol is presented. Asynchronous ÷ 2 dividers in cascade accompanied with phase switching technology are used to eliminate the glitch when divide ratio changes at 2.4 GHz. The uncertainty problem of the initial phase due to the phase switching technology is solved by checking the characteristic signals of the initial phase. The results of simulation show that the circuit has good stability and breaks the speed limitation of frequency synthesizer; the power dissipation of the whole circuit can be reduced by adjusting the prescaler in appropriate DC level. In addition, this kind of divider has large-scale divide ratio and can be applied to different designs.