软件无线电中数字上下变频器研究与实现，适合通信专业人员参考-Digital Software Radio Research and Implementation of up and down converter for communication professionals reference

vhdl硬件设计实现一个数字上变频器，实现数字上变频-vhdl hardware design on the realization of a digital converter, digital up-conversion

V/F变换和F/V变换采用集成块LM331，LM331是美国NS公司生产的性能价格比较高的集成芯片，可用作精密频率电压转换器用。LM331采用了新的温度补偿能隙基准电路，在整个工作温度范围内和低到4.0V电源电压下都有极高的精度。同时它动态范围宽，可达100dB；线性度好，最大非线性失真小于0.01％，工作频率低到0.1Hz时尚有较好的线性；变换精度高，数字分辨率可达12位；外接电路简单，只需接入几个外部元件就可方便构成V/F或F/V等变换电路，并且容易保证转换精度-V/F conversion

The LDS6100/6120 family of capacitance touch controllers Integrated Device Technoogy® is optimized for the implementation of touch-based input controls including sliders, scroll wheels and buttons. A low power programmable capacitance-to-digi