摘要
设计了一种负载能力自动可调的低功耗电流源.由单片机控制电流环芯片AD421产生4-20 mA电流输出,通过电流取样反馈实现精密电流监控与调整.分析了AD421供电电压和电流源负载能力之间的关系,通过单片机休眠、环路闭合状态检测与电源控制、环路负载检测与电源功率控制等方法降低功耗.经测试电流源精度高,能够自动调整负载能力,且整机功耗低.
A low-power current source with automatically adjustable load capacity was designed in the paper. The microprocessor controlled the current loop chip AD421 to generate 4-20 mA current. The output current was monitored and adjusted via current sampling circuits. The relationship between supply voltage on AD421 and load capacity was analyzed. According to the result,several methods such as MCU sleep mode using,loop state detecting and controlling,load detecting and power regulating were adopted to reduce power consumption. Tests result show that the current source was characterized with high precision ,load automatically adjustment,low power consumption.
出处
《自动化与仪表》
北大核心
2014年第7期73-76,共4页
Automation & Instrumentation
基金
国家自然科学基金青年基金项目(51304231)
