ADS1204 模数转换对应值

在ADS1204中2V对应的16位数字量是多少呢？-2V对应的又是多少？

在芯片手册上只看到以下这段话：A differential input signal of 0V will ideally produce a stream of ones and zeros that are high 50% of the time and low 50% of the time. A differential input of +2V produces a stream of ones and zeros that are high 80% of the time. A differential input of –2V produces a stream of ones and zeros that are high 20% of the time. 

其实意思说得很明白，－2V 输入，对应输出信号中，20％ 为高电平。

你可能并没有理解这个 ADC 的输出特性。他是用信号占空比来表征转换结果的。

好好理解一下这张图