Function signal generator

The invention discloses a function signal generator. The function signal generator comprises a phase accumulator which is used for carrying out phase accumulation under the effect of a first clock according to a frequency control word input by a user, a waveform lookup table which is used for storing waveform data and outputting corresponding waveform data according to a waveform lookup table address, a digital to analog converter which is used for converting the waveform data into a waveform signal under the effect of the first clock, a low-pass filter which is used for filtering out glitch noise in the waveform signal and outputting the waveform signal, and a clock conversion module which is used for generating a tunable virtual sampling clock according to the phase accumulator and generating the waveform lookup table address under the effect of the virtual sampling clock. According to the specific embodiment of the invention, the clock conversion module is comprised; through the phase accumulator, the tunable virtual sampling clock is generated, and the waveform lookup table address is generated under the effect of the virtual sampling clock; and through a programmable logic device, the sampling rate of the function signal generator is changed without a clock generation chip.