ST STM32MP257F-EV1 User Manual page 40

7.17 VBAT connector
7.17.1 Description
The VBAT connector allows a power mode that maintains critical operations when a power loss occurs on VDDIO.
The VBAT power domain contains the RTC, the backup registers, the retention RAM, and the backup SRAM. To
enable VBAT mode, a backup power source must be connected to the VBAT connector.
7.17.2 Operating voltage
The VBAT connector enables external power supply from 2.3 to 3.6 V.
7.17.3 VBAT interface
Table 30 describes the I/O configuration of the VBAT interface.
I/O
1
2
Figure 22 shows the pinout of the VBAT connector (CN11).
Table 31 describes the VBAT interface and pinout of the CN11 connector.
I/O
1
2
UM3359 - Rev 2
Table 30. I/O configuration of the VBAT interface (CN11)
Figure 22. VBAT connector (CN11) pinout
Table 31. VBAT connector (CN11) pinout
Pin name
VBAT
GND
Configuration
VBAT
GND
2
1
Function
VBAT supply
Ground
UM3359
Board functions
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