ST STM32F20 Series - Power Supplies

Power supplies AN3320
6/29 Doc ID 18267 Rev 2
1 Power supplies
1.1 Introduction
The device requires a 1.8 V to 3.6 V operating voltage supply (V
DD
), excepted the WLCSP
package witch requires 1.65 V to 3.6 V. An embedded regulator is used to supply the
internal 1.2 V digital power.
The real-time clock (RTC) and backup registers can be powered from the V
BAT
voltage when
the main V
DD
supply is powered off.
Figure 1. Power supply overview
1. V
DDA
and V
SSA
must be connected to V
DD
and V
SS
, respectively.
2. The voltage on V
REF
ranges from 1.65 V to V
DDA
for WLCSP64+2 packages.
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