块DDS芯片中主要包括频率控制寄存器、高速相位累加器和正弦计算器三个部分（如Q2220）。频率控制寄存器可以串行或并行的方式装载并寄存用户输入的频率控制码；而相位累加器根据dds频率控制码在每个时钟周期内进行相位累加，得到一个相位值；正弦计算器则对该相位值计算数字化正弦波幅度（芯片一般通过查表得到）。DDS芯片输出的一般是数字化的正弦波，因此还需经过高速D/A转换器和低通滤波器才能得到一个可用的模拟频率信号。

-In the programming step, the electronic controller fills the memory with data. Each datum is a binary word representing the amplitude of the signal at an instant of time. The array of data in the memory then forms a table of amplitudes, with time implied by the position in the table. If, for example, the first half of the table were filled with zeroes and the second half with values of 100 , then the data would represent a square wave. Any other wave shape can be created simply by altering the data.



Devices are also available that cannot be programmed, and can only output sinewaves or a small number of waveforms.