A Hybrid Four-Switch Inductor-First Quadratic Step-Down Converter With Internal Ripple Compensated COT Control

With the proliferation of artificial intelligence (AI), cloud computing, and the Internet of Things (loTs), the power demanded in data centers is growing rapidly. The power supply with an input voltage bus of 12 V or 24 V is widely used in data centers, while the supply voltages of the point-of-loads (PoL) have been reduced to 1 V due to the development of CMOS technology. Therefore, DC-DC converters with high voltage conversion ratio (VCR) and high efficiency are required. The converter with double step-down (DSD) [1]–[3] topology is proposed and the high VCR is achieved. However, the input current is not continuous and the Electro-Magnetic Interference (EMI) is large. Furthermore, the loss of the direct current resistance (DCR) is large in the topology that the inductor is directly connected to the load as shown in Fig. 1 (top left). Fig. 1 (top middle) shows that the DCR loss can be reduced up to 50% by using inductor-first (IF) topology. However, the conventional inductor-first topology shown in Fig. 1 (top right) is not suitable for the high voltage conversion application.