A New Type Of Slope Compensation Circuit Based Boost Driven Design

In the modern society, the mobile terminal such as mobile phones and laptops are becoming more and more popular in our daily life, which are generally small and cost lower power, and that explains why controlling the size and enhancing the efficiency of the power supply is so important. Due to the characteristics of small size and high efficiency, switch-mode power supplies are widely used in portable devices.The peak current mode is generally used as the controlling method of switch-mode power supplies, although comparing to other control methods it has some advantages, it needs slope compensation circuit to cancel the sub-harmonic oscillation which happens at the half of the switch frequency. The structure of the slope compensation circuit is generally complicated, it also affects the speed of the loop response and load capacity of the system. A new slope compensation circuit is presented and used as a part of the BOOST driver circuit, which has a simple structure and fast speed of loop response. It also has an adaptive function, which makes the circuit apply in a greater range. The article will first illustrate the principle of the switch-mode power supply before designing circuit, and then will introduce the topology which stress on BOOST, finally the introduction of the two controlling methods will be presented, and will compare differences between the two.In the part of circuit design, it will firstly design the structure of the system, include system architecture, the choice of the external element and the realization of the compensation circuit, and then will be simulated and tested by Saber which is a EDA software. After that sub-circuit will be presented and a new slope compensation circuit will be introduced according to the design of the system. The Hspice is used to test the sub-circuit finally.When the system and sub-circuit design are accomplished, the Hspice is used to test and simulate the function and the performance of the whole circuit, the performance of the new slope compensation circuit in the whole circuit will be presented.Through the system co-simulation, this work fully meets the design target requirements, the design theory and practical application is a worthy attempt.