
Power control (PWR)
RM0453
220/1454
RM0453 Rev 2
The different supply configurations are shown in the figure below.
Figure 19. Supply configurations
The LDO or SMPS step-down converter operating mode can be configured by one of the
following:
•
by the MCU using the SMPSEN setting in
PWR control register 5 (PWR_CR5)
, that
depends upon the MCU system operating mode (Run, Stop, Standby or Shutdown).
•
by the sub-GHz radio using
SetRegulatorMode()
command and the sub-GHz radio
operating mode (Sleep, Calibrate, Standby, Standby with HSE32 or Active).
After any POR and NRST reset, the LDO mode is selected. The SMPS selection has priority
over LDO selection.
While the sub-GHz radio is in Standby with HSE32 or in Active mode, the supply mode is
not altered until the sub-GHz radio enters Standby or Sleep mode. The sub-GHz radio
activity may add a delay for entering the MCU software requested supply mode.
The LDO or SMPS supply mode can be checked with the SMPSRDY flag in
.
Note:
When the radio is active, the supply mode is not changed until after the radio activity is
finished.
During Stop 1, Stop 2 and Standby modes, when the sub-GHz radio is not active, the LDO
or SMPS step-down converter is switched off. When exiting low-power modes (except
Shutdown), the SMPS step-down converter is set by hardware to the mode selected by the
SMPSEN bit in
PWR control register 5 (PWR_CR5)
. SMPSEN is retained in Stop and
Standby modes.
Independently from the MCU software selected supply operating mode, the sub-GHz radio
allows the supply mode selection while the sub-GHz radio is active (thanks to the sub-GHz
radio
SetRegulatorMode()
command
)
.
The maximum load current delivered by the SMPS can be selected by the sub- GHz radio
SUBGHZ_SMPSC2R register. For more details see
Section 5: Sub-GHz radio (SUBGHZ)
.
MSv50974V1
LDO/SMPS
LDO/SMPS supply
LDO supply
RF
LDO
MR
LPR
V
DDRF1V5
V
FBSMPS
V
LXSMPS
V
DDSMPS
V
DD
LDO/SMPS
RF
LDO
MR
LPR
V
DDRF1V5
V
FBSMPS
V
LXSMPS
V
DDSMPS
V
DD