Design and Implementation of Grouping A /D Conversion Based on SPI Interface Isolation
LIANG Zheng-zheng;LIU Yong-qiang;JING De-sheng;Xi'an Aeronautics Computing Technique Research Institute,AVIC;
Many embedded system control multiple actuators or devices currently. Each actuator or device needs to be controlled independently to avoid single actuator or device invalidation from causing the whole system paralyze. According to this demand,a lot of systems request the control signals and the feedback signals of actuators or devices to be isolated mutually. This article analyses the characteristics of various isolation method,the merit and shortcoming of isolation node and isolation interface choice for meeting the application demand,and describes the design reason of realizing analog signal acquisition of different units based on SPI interface isolation. In addition,this article expounds detailed method of designing the power voltage acquisition unit of a launch control system for instance.