This mode is for applications needing ultra-low
power applications. The device can either be
powered using two rails (1.8 V and 1.2 V) or with
three rails (3.3 V, 1.8 V and 1.2 V).
Figure 7-3 Power Optimized Mode Power Management
(Left: 1.8V I/O Topology, Right: 3.3V I/O
Topology)