Part Number: ADS9218
Other Parts Discussed in Thread: ADS9219, ADS9217
This question applies not only to this specific device, but to the entire family. I have seen similar questions raised previously; however, the datasheet appears misleading with respect to the 10 MHz and 20 MHz variants when operated in 1-lane mode. Tables 7-7, 7-8, and 7-9 should explicitly and unambiguously state the applicable conditions for 1-lane versus 2-lane operation.
Aside from Table Note 2—which is positioned incorrectly in the table (and, according to a forum post from approximately one year ago, is scheduled to be corrected)—the documentation suggests that 1-lane mode is supported without limitation. In our intended use case (24-bit DDR, 1-lane, 10 MHz), there is no obvious reason to consult this table note, and a reader would reasonably conclude that 1-lane operation is fully supported.
To be clear, for the ADS9218 and ADS9219: does 1-lane mode only function when data averaging is enabled, regardless of the sampling frequency? For example, if the device is operated at 5 MHz with no averaging, should this configuration work as expected, similar to the ADS9217?
As a broader suggestion, it may be beneficial to split the documentation into separate datasheets—one for the ADS92x7 family and another for the ADS92x8/ADS92x9 family. The functional differences between these devices are significant, and consolidating them into a single datasheet makes these distinctions difficult to follow.
