针对集成电路工艺容差所引起的器件偏差,设计了一款RC时间常数测量电路,适用于GSM系统的多相滤波器模块。电路采用可编程电容阵列,可快速调谐,以保证模块稳定。仿真结果表明,采用5位数控方式调谐电容阵列,调谐时间误差不超过三个时钟周期,满足系统要求。 Aiming at the device deviation caused by the process tolerance of integrated circuit, a RC time constant measurement circuit is designed and applied to the polyphase filter module of GSM system. The circuit uses a programmable capacitor array can be quickly tuned to ensure module stability. The simulation results show that using 5-digit CNC tuning capacitor array, the tuning time error does not exceed three clock cycles to meet the system requirements.