Eddy current testing excitation signal source based on DDS (Direct Digital Synthesis) technology

The invention discloses an eddy current testing excitation signal source based on a DDS (Direct Digital Synthesis) technology, and the eddy current testing excitation signal source comprises a singlechip, a CPLD (Complex Programmable Logic Device) module, a waveform memory, a D/A (Digital-to-Analogue) converter, a low-pass filter, a power amplification circuit, a liquid crystal touch screen and an upper PC (Personal Computer) machine, wherein the liquid crystal touch screen is connected with the singlechip; the upper PC machine is connected and in series communicated with the singlechip; the CPLD module is connected with the singlechip; the waveform memory is connected with the singlechip and the CPLD module; the D/A converter is connected with the singlechip and the CPLD module, and the D/A converter is connected with the low-pass filter; and the low-pass filter is connected with a power amplifier. The eddy current testing excitation signal source disclosed by the invention can generate standard excitation signals, namely sine waves, pulse waves, and the like with parameters easily adjusted, and excitation signals with any waveforms for eddy current testing.