Chip Design Of AC-DC Switching Mode Power Supply With Multiple Protection And Low Power Consumption

Compared to the traditional linear voltage source, the Switching power supply has the advantage of lignt weight, high efficiency, small size high stability and low cost. Energy saving is the theme of our new are, the Switching power supply shown strong vitality in the application of modern electronic devices, Whether in aerospace, or electronic digital products, the switching power supply witch has the advantage of low power, and high efficiency have been widely used.The chip with undervoltage protection, overvoltage protection, overcurrent, overtemperature protection features can deal with a variety of possible failures. line voltage feed-forward function increases the Corresponding speed if the input voltage momentary fluctuations. In addition, the chip integrated high voltage power MOSFET whitch can not only save costs in the power supply design, but also can improve the chip’s drive performance and stability. Programmable current limit can meet the needs of different power supply. In accordance with the load demand the Chip can work in skip mode, low-frequency mode, frequency mode and full-frequency mode, whitch can make the power supply get higher efficiency over the entire load range.In chapter two the paper introduces the basic topology of the switching power firstly. Then two basic switch loss is analyzed, the Switching losses and conduction loss. The architecture of the chip is described which can help to understand the function of the chip from the top. In chapter three, the protection circuits relating to the chip were designed, the specifications is designed and verified. In chapter four, the chip’s power consumption is analyzed specially. The chip’s power consumption is optimized from the normal operation and f fault mode. In the normal mode the chip’s power consumption is reduced by changing the operating frequency to meet the needs of different load. In fault mode, auto-restart circuit is designed to make the chip operate in the low power standby mode. In chapter five, the chip’s simulation results were offered when the power suplly worked in normal operation and fault mode. The chip tapeout with TSMC0.5μm. The test solutions is designed, what’s more, the test results were analyzed in every Operating Mode.