給出了一種基于FPGA 的等占空比任意整數分頻電路的設計方法。首先簡要介紹了FPGA 器件的特點和應用范圍, 接著討論了一些常見整數分頻的方法, 而本文運用一種新的可控分頻器設計方法——脈沖周期剔除法, 主要是對半周期進行計數, 配合時鐘反相電路, 可以實現占空比50% 的任意整數分頻, 分頻系數由控制端給定。本設計在M ax+ P lusê開發軟件下, 利用VHDL 硬件描述語言和原理圖輸入方式, 可以方便地實現分頻器電路的設計。在文中給出了N = 3 時分頻電路設計, 并對電路進行了仿真和測試, 實驗結果符合設計要求。
Th is paper gives out a design of the equal duty rat io arbit rary integer frequency divider based on FPGA 1 F irst int roduces the characterist ics and app licat ion domain of FPGA in brief1 Then discusses a few t radit ional integer frequency dividers1 But th is paper p resents a new concep t of p rogrammable frequency divider1A n algo rithm based on the new concep t is int roduced also1U sing th is method can realize 50% duty rat io integral frequency division1 The frequency division coefficient is given by cont ro l end1 The frequency divider is described in VHDL , and synthesized, simulated w ithM ax+ P lusê foundat ion1L ast, the N = 3 design p ract ice based on the algo rithm is given, the experimental results show that the perfo rmance has confo rm to the p ropo sed algo rithm1