Abstract: A high precious and controllable constant current module is designed, basing on the principle of single-ended flyback switching power supply. Then, the detailed design and calculation process of some key circuit parameters are proposed. Finally an experiment is taken to test its constant current accuracy and controllability. In addition, this module can be used for excitation signal transmission systems of DC resistivity method, induced polarization method and other different electrical advanced detection methods.

Key words: advanced detection, high precious, constant Current, switching power supply