Design And Analysis Of Isolated DC-DC Converter Based On Chip-scale Transformer

With the rapid development of electronic technology,power technology becomes essential for scientific and technological strength have a very important role in people’s daily lives.It usually require isolation between circuit elements for security and data integrity reasons.Isolation power in the low-power and low-voltage situation is limited by the cost. A new isolated power solutions at this time is particularly significance.The main topic of this project is to design a monolithic isolated DC-DC power management chip which can supply a digital signal and analog power in the same time.Isolated power is fully integrated in a single chip that don’t need a lot of peripheral devices providing 5V or 3.3V output isolation voltage and maxium output power of 0.5W.It is mainly used in low-power,low-cost applications to provide a relatively constant output range of 34% conversion efficiency from the heavy load to light load.With chip scale transformer using magnetically coupled isolation, in order to improve efficiency, primary-side power oscillator produces power signal provided by LC resonant 180 MHz to the secondary side through the full bridge rectifier and voltage feedback control loop to stabilize the output voltage. the feedback signal control the resonant LC tank components directly rather than control the transformer swich enabing efficient power transmission and obtain a stable voltage.Firstly,this thsis presented the general description of the isolation technology,introduces and analyzes the development status and trends,and then elaborated on the basic principles of swiching power supply,focusing on the circuit structure,operating principle and simulation of the bias circuits,voltage reference circuits,triangle wave circuit,undervoltage lockout module,the error amplifier and primary side oscillator modules. Focus on the functionality and performance verification overall circuit simulation results and further describes physical design.Finally,complete the design task successfully.