DDS的工作原理是以数控振荡器的方式产生频率、相位可控制的正弦波。电路一般包括基准时钟、频率累加器、相位累加器、幅度/相位转换电路、D/A转换器和低通滤波器（LPF）。频率累加器对输入信号进行累加运算，产生频率控制数据X（frequency data或相位步进量）。相位累加器由N位全加器和N位累加寄存器级联而成，对代表频率的2进制码进行累加运算，是典型的反馈电路，产生累加结果Y。幅度/相位转换电路实质上是一个波形寄存器，以供查表使用。读出的数据送入D/A转换器和低通滤波器。-DDS works the way we are digitally controlled oscillator frequency, phase controlled sine wave. Circuits generally include reference clock, frequency accumulator, phase accumulator, amplitude/phase converter circuit, D/A converter and low-pass filter (LPF). The frequency accumulator to accumulate the input signal operation to produce the frequency control data X (frequency data or phase stepping volume). From the N-bit phase accumulator and the N-bit full adder cascade accumulation register is made on behalf of the frequency of the two binary codes accumulation operation, is a typical feedback circuit, resulting in cumulative results of Y. Amplitude/phase converter circuit is essentially a waveform register for look-up table to use. Read out the data into the D/A converter and low pass filter.