a novel peak current PWM/PFM dual-mode boost dc-dc regulator applying for neural signal regeneration is proposed in this paper. The converter can adaptively switch between pulse-width modulation (PWM) and pulse-frequency modulation (PFM) both with relatively high conversion efficiency. Soft-start circuit is designed to eliminate the surge current at the start up stage of the regulator, other protection modules are also contained. The paper analyzes the model and stability of the system. The operation frequency of the regulator is 1MHz. The simulation results show the efficiency of the system is relatively high in PWM mode, up to 95%, in PFM mode it also has good efficiency.
Soft start-up scheme for the hybrid distribution transformer