ST STM32H7B3I-EVAL, User Manual

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6.3.3 Board power supply - SMPS / LDO configuration
Figure 10. MCU Power : SMPS / LDO
STM32H7B3I-EVAL supports four “SMPS / LDO” configurations of the STM32H7B3LIH6QU microcontroller
described in
Table 10 :
1. LDO supply only
2. SMPS supply only (Default configuration)
3. SMPS and LDO supplies cascaded
4. SMPS and LDO supplies (SMPS supplies 1V8 to board as well)
Some PCB reworks are needed to change power configuration as shown in Table 10 :
Table 10. Internal SMPS / LDO and board configuration
Signal name Setting
Supply config 1:
LDD only
Supply config 2:
SMPS only
(1)
Supply config 3:
SMPS and LDO
cascaded
Supply config 4:
external SMPS
- Figure 11 Figure 12 Figure 13 Figure 14
SMPS OFF ON ON ON
LDO ON OFF ON ON
3V3_MCU = VDD_LDO SB37 X - - -
VFBSD = GND R251 X - - -
3V3_SMPS_IN = GND SB10 X - - -
3V3_MCU = 3V3_SMPS_IN R22 X X X X
VDD_SMPS_IND_OUT = VDD_LDO SB3 - X X X
VDD_SMPS_IND_OUT = VCAP SB5 - X - -
VCAP capacitor C121 2.2 uF 100 nF 2.2 uF 2.2 uF
VCAP capacitor C126 2.2 uF 100 nF 2.2 uF 2.2 uF
VFBSD = VCAP R263 - X - -
VFBSD = VDD_LDO R262 - - X X
VDD_SMPS_IND_OUT = 1V8_AO SB4 - - - X
1V8_AO capacitor C21 - - - X
1. The default setting is in bold.
UM2662
Power supply
UM2662 - Rev 1
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