When hypothetical conditions of sampling time and data precision are sufficed , a / d574 was choosed . not only the a / d574 has low cost and convenient interfaces , but also because the a / d apply more converters and the information of it gathering is handy A d转换器在满足采样时间和数据精度的前提下,尽量选取了市场供应量大,价格低廉,接口方便的a d574 ,这种a d转换器应用较多,资料收集方便。