specified to 5.5V. Is there any reason for these differences?
For the isolated ADM3053 with the integrated DC-DC isoPower:
The VCC is transferred to the secondary side, and is rectified and regulated to
5 V to supply the CAN transceiver.
For the isolated ADM3052 with Integrated V+ linear regulator:
The linear regulator takes the V+ bus power (ranging between 11 V to 25 V) and
regulates this voltage to 5 V to supply the CAN transceiver.
The isolated ADM3054 does not contain an integrated voltage regulation feature.
The 4.75 V ≤ VDD2 ≤ 5.25 V range ensures correct operation of the CAN
transceiver. This has been confirmed with the part designer.