Abstract: To meet the needs of different beam energy waveforms output of heavy ion medical machine (HIMM) synchrotron RF system, a synchronous signal source that can output different cavity voltage and bias current waveforms has been designed and realized. The ARTERA's FPGA is used as the core processing element to receive and process multiple sets of cavity voltage and bias current waveform files. And DAC is used to output waveforms after receiving synchronous optical trigger signal. The system enables seamless switching of different beam energy. The results show that the signal source is stable and can realize seamless switching and synchronized output waveforms. Its performance fully meets the requirements of the HIMM system for accelerating and capturing carbon ions. Compared with commercial arbitrary waveform generator, this system is cheaper and the modular design is easy to integrate. It can also be widely used in other occasions which need arbitrary waveform signals.