Package design and PI simulation of AC-DC circuit

With the development of portable electronic equipment, the power density and volume of power adapters have attracted more and more attention. Using high-frequency switching elements to reduce the volume of inductive elements, PFC circuit to improve the power factor and reduce the volume of capacitive elements, using highly integrated elements is a common method. When using high-frequency switching elements, the power integrity, signal integrity, and impedance matching of high-frequency signal lines should be considered. The design of power management SOC faces the disadvantages of the long development cycle and high investment cost.This paper presents a system packaging scheme, which encapsulates the key components of PFC and LLC step-down circuits, rectifier soft bridge, and two-stage step-down circuit [1]. The module realizes the functions of 150V-250V DC wide voltage input, 20V and 5V DC output. The package interconnection model is established and imported into ANSYS software for simulation. The power integrity of the power supply network is analyzed, the planar resonance point of the power supply is explored, and the decoupling optimization is carried out [2]. Through simulation analysis, the layout of power and signal wiring is optimized. Through optimization design, the module achieves the maximum voltage drop of 5V within 5%, and the PDN meets the impedance requirements within the target frequency, meeting the design requirements. The miniaturization and integration of modules can be realized by system-level packaging of DC-DC circuits. The results show that the scheme is advanced and feasible.