一种双向大电流负载开关芯片的设计

ABSTRACTABSTRACTIn recent years,with the advent of many new portable electronic products,such aswearable electronics,5G smartphones,tablets,and bio-implantable and bio-injectableantennas.Not only are they small in size,light in weight,and versatile,they also havelonger charging intervals and require higher power performance.In order to save electricityin daily use,in addition to applying a high-efficiency power management chip,multipleload switches are required,and the microprocessor is used to control the load management.In different working states,power is supplied to the useful load,which will All unusedloads are shut down.Load switch IC is a power supply IC with small size,low voltageoperation,low on-resistance,and low quiescent current.Compared with traditional discretepower supply structures,the use of load switches helps to significantly reduce the size ofpower ICs.And energy saving,and can play a good role in protecting the load,so it isloved by power IC designers.Based on the research on the development status of load switch ICs,this paper designs abidirectional high current load switch chip for high voltage and high current resistantproduct applications.This load switch IC has a wide input voltage operating range from 3Vto 20V.Provides a maximum continuous load current of 5A;In addition,the chip can alsoprovide input over-voltage protection,over-temperature protection,under-voltage lockoutand reverse blocking of output voltage,while also supporting USB charging and OTGautonomous switching.The chip is mainly used in smart phones,handheld devices,tabletcomputers and other portable devices.This paper first systematically studies the basic principle and structure of load switches,provides theoretical guidance for the design of bidirectional high current load switch ICs,and then combines the characteristics of traditional load switches with low output currentand no OTG function,and proposes a bidirectional high current load.The implementationmethod and overall structural block diagram of the switch chip,and then specific design ofthe corresponding sub-module circuit,and use Spectre software under Cadence tools tobuild the circuit,using 0.18um BCD process to complete the simulation analysis of therelevant sub-module circuit,and finally the chip as a whole The circuit was functionallyverified.Keywords:surge protection;over-voltage protection circuit;reverse current blocking;over-temperature protection