Design Of Single-chip Multi-function DC/DC Converter

With the development of electronic design integration, switching mode power converter chip is widely used in telecommunications, micro-computers, consumer electronic products and other fields. To meet the market's demand, a single-chip multi-functional DC/DC converter is designed.After analyzing the principle of DC/DC switching converter and its control mode, the single-chip multi-functional DC/DC converter's control loop and its structure are designed. In order to improve the chip's efficiency and cut down its power loss, a new pulse frequency modulation is used, which can reduce the switch's turn-on time by current limiting circuit based on the tradional PFM. The chip's core module circuits are designed and verified by Hspice. Based on Cadence ADE and Xi Yue's 3μm/40V Bipolar process model, the whole chip is simulated with Spectre, and the simulation results verify the feasibility of the circuit design and the correctness of theoretical analysis. Finally the chip layout design is completed and verified by the DRC and LVS.After taped out the chip at Xi Yue, it is used to constitute switching converters such as Boost, Buck and Buck-Boost converter. The test result verified that it can constitute many kinds of switching converters based on minimal external components. The chip has short-circuit current limiting, good load regulation, fast transient response and other characters.