In this PDN, VDD_CORE is operating at 0.75V
and supplied by the multi-phase Buck1/2/3. VDDR_CORE is supplied
by LDO3 (0.85V). However, if BUCK1/2/3 is configured to output
0.85V, then both CORE rails (VDD_CORE and VDDR_CORE) must be
supplied by BUCK1/2/3 and LDO3 becomes a free resource. Per
AM62A data sheet, VDD_CORE and VDDR_CORE are expected to be
powered by the same source so they ramp together when VDD_CORE
is operating at 0.85V. LDO3 is configured to be part of the
TPS65931211-Q1 power-up sequence and requires an input supply as
well as the input/output capacitors to prevent an LDO3 fault
condition. The state of GPIO6 sets the output voltage on the
multi-phase Buck1/2/3. See
Section 3.2 for information about polarity of digital pins.