基于SPI接口隔离的分组A/D转换设计与实现

系统需要控制多个执行器或多个设备,每个执行器或设备又要求控制相对独立,避免单个执行器或设备失效导致整个系统瘫痪。基于此需求,很多系统要求各个执行器或设备的控制信号和反馈信号与控制器相互隔离。从应用需求出发分析了各种隔离方式的特性、隔离点和隔离接口选择的优缺点,阐述了基于SPI接口隔离实现不同单元模拟量采集的设计原因,以某发射控制系统的电源电压采集单元作为示例,验证设计方案及实现方法。

Design and Implementation of Grouping A/D Conversion Based on SPI Interface Isolation

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 i- solation 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.