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| 摘要: |
| 描述了应用DSP56F807及其内部A/D实现交流采样的方法,对于出现的电磁干扰下的零漂问题,利用PSpice电路分析软件,对电路中使用的多种二阶滤波方案(无源二阶滤波,滤波电容接Uos或接地,无源二阶滤波加运放跟随,滤波电容接地以及有源二阶滤波电路中相应电路)进行分析,给出在该类应用中可行的无源二阶滤波、滤波电容一端接地方案,并解决了干扰下的零漂问题。分析基准电压回路的电路设计,通过增大并联电容或供电电源的容量,解决了动态工作下的零漂问题。 |
| 关键词: DSP,单极性A/D,交流采样,抗干扰,二阶滤波 |
| DOI： |
| 分类号:TM930 TN47 |
| 基金项目: |
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| AC sampling anti-interference design based on inner A/D of DSP56 F 807 |
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JING Zhan
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| Abstract: |
| A method of AC sampling applying DSP56 F 807 and its inner A /D converter is described.To solve the zero drift problem appeared in electromagnetic disturbance,several 2 nd order filtering schemes are analyzed with PSpice,including passive or active 2 nd order filter with or without amplifier and follow-up circuits while filtering capacitor connected to Uo s or ground.A feasible scheme of passive 2 nd order filter with one end of filtering capacitor grounded is presented.Based on the analysis of benchmark voltage circuit design,the zero drift in dynamic condition is solved by increasing capacitance of the parallel capacitor or the power supply. |
| Key words: DSP,monopole A /D,AC sampling,anti-interference,2nd order filter |
