A novel digital soft-start circuit for dc-dc converter

This paper proposes a novel quick soft-start method for the digital control dc-dc converter. To implement the energy management for energy saving, the power supply that can be operated in start-up and be shuttled down quickly and continually is necessary. It is the power supply added to the soft-start capability. It is important for the soft-start operation to detect the load resistor. In the conventional analog control method, the fixed large time constant of the soft-start circuit must be set corresponding to the worth condition. In the proposed digital control, the optimal time constant of the soft-start circuit can be decided with load resistor with the control processor. Therefore, it doesn´t need to set the large value for the time constant. As a result, the convergence time of output voltage is suppressed. From simulation results, it is confirmed that the digital control method has superior soft-start characteristics compared to the analog one and the convergence time of output voltage is approximately 94% smaller than the analog one.