Design Of The Chip Based On The AC/DC Switching Power Supply

Nowadays, electronic equipments are widely used in our daily life, power supply is anintegral part of these electronic equipments. A stable and reliable power supply is needed notonly in our daily life, such as mobile phones, chargers and etc; but also in education andaerospace field, such as laser pointer, microphone. Power conversion technology has beenwidely used. This article is based on the background of the research of switching mode powersupply(SMPS).In this thesis, firstly the background and development of the SMPS is introduced. With this,writer gives the basic understanding of the SMPS. Second, basic principles and topology ofSMPS are described, especially the topology of the fly-back SMPS which can provide atheoretical basis for circuit design. Then, with the given design requirements and block diagram,the simulation of each module circuit is performed. At last, system platform is built, testing andcertification is achieved.Current mode PWM control and CC/CV mode is used in this chip, this greatly improvedthe response speed and efficiency of the system. An AC sampling circuit is added in front of theError Amplifier. Significant cost savings is achieved by eliminating the external TL431andoptocoupler. Meanwhile, EMI is reduced by adding frequency jitter circuits to the oscillator.Different kinds of built-in control, regulation and protection circuits are included in this chip,that makes the chip has a wide range of application in the primary side fly-back power AC/DCSMPS areas.The design in this thesis is implemented based on HuaHong1um40V high voltage process,the simulation is achieved in Cadence. The simulation results obtained show that the circuitstructure and performance meet the spec well.