FDC2112手册第17页，关于转换时间的描述，这一段是怎么得到1.8ms，3.2ms，0.75ms以及最终的16.75ms的？
能描述一下计算过程吗？
The deterministic conversion time of the FDC allows data polling at a fixed interval. For example, if the
programmed RCOUNT setting is 512 FREF cycles and SETTLECOUNT is 128 FREF cycles, then one conversion
takes 1.8ms (sensor-activation time) + 3.2ms (conversion time) + 0.75ms (channel-switch delay) = 16.75ms per
channel.
