A compact, resource sharing on-chip soft-start technique for automotive DC-DC converters

This paper proposes on-chip soft-start method with minimum extra components and turbulence free start up of dc-dc converter. During the soft start, the output voltage is slowly increased to the steady state value so that the inrush current and overshoots are prevented. The proposed topology is implemented in buck converter designed to give 3.3V output for wide supply range of 4.5V to 18V and load range of 0 to 3A in AMS 0.35μm high-voltage CMOS process. Experimental results show that the novel on-chip soft-start circuit is able to reach to steady state voltage without massive inrush current and overshoot in 36 us of time