The Design And Realization Of A Monolithic Integrated Ac / Dc Switching Power Supply Chip

With the developing of the electronic science and technology and the widely use of electronic products, the electric power and electronic technology is becoming more and more important. Most of electric systems can not utilize residential electricity power (AC voltage) directly so that these power must be converted to required DC voltage. Because it has advantages high accuracy, lower cost, high efficiency, good reliability and small size, the swithed mode power supply is widely utilized in AC/DC convertion.The objective of this work is to design and realize a monolithic off-line AC/DC SMPS switcher. The chip has characteristics of built-in 700V power MOSFET, dynamic self-supply, no need for an auxiliary winding, internal 1.0ms soft-start to prevent inrush current when power on, frequency jittering for better EMI signature, skip mode operation at low load without acoustic noise, over voltage protection, over current protection, over load protection and thermal shutdown.This desertation introduces the fundamentals of SMPS, especially AC/DC application theory and internal block of this chip. Then it presents the detail of the circuit design and simulation result, including reference, regulator, oscillator, frequency jitter, soft start, FB controller, thermal shutdown. At last, the thesis introduces the whole layout of this chip and the post layout simlation...