Hi entechbob,
If you are asking what the “Isolated Power” feature is, it means that it can pass power from the Host side to the Device side across an isolated barrier. This allows one to power isolated devices from the host without having to provide a separate power supply for the device.
Essentially, the LTM2884CY#PBF is a single-device interface providing both power and USB communication across an isolated barrier to an end device.
The ADUM4160BRIZ-RL provides an isolated USB interface, but it does not provide power across that barrier, so each side will require its own supply. You can make something functionally equivalent to the LTM2884CY#PBF by designing in both the ADUM4160BRIZ-RL and a separate isolated power supply. We can help you select such a device, if interested.
The most similar item we have in stock is the NMUSB202MC-R7. It is functionally very similar, but the board layout is not the same, and the height is significantly taller (14.5mm vs. 5.2mm).
So, if your device side (downstream side) does not have its own supply, you need to provide that either with an integrated device (isolated power and USB communication) or with a separate supply.