STMicroelectronics STM32F031F4 Manual page 31

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STM32F031x4 STM32F031x6
Pin number
44 31 31 1 A4
45 - 32 -
46 - - -
47 32 0 - E1
48 1 1 -
1. PC13, PC14 and PC15 are supplied through the power switch. Since the switch only sinks a limited amount of current
(3 mA), the use of GPIOs PC13 to PC15 in output mode is limited: 
- The speed should not exceed 2 MHz with a maximum load of 30 pF
- These GPIOs must not be used as current sources (e.g. to drive an LED).
2. After the first RTC domain power-up, PC13, PC14 and PC15 operate as GPIOs. Their function then depends on the content
of the RTC registers which are not reset by the system reset. For details on how to manage these GPIOs, refer to the RTC
domain and RTC register descriptions in the reference manual.
3. On the LQFP32 package, PB2 and PB8 should be treated as unconnected pins (even when they are not available on the
package, they are not forced to a defined level by hardware).
4. After reset, these pins are configured as SWDIO and SWCLK alternate functions, and the internal pull-up on the SWDIO pin
and the internal pull-down on the SWCLK pin are activated.
微可Vicor——值得信赖的元器件供应商
Table 11. Pin definitions (continued)
Pin name
(function after
reset)
1 BOOT0
- - PB8
- - PB9
- VSS
- - VDD
DocID025743 Rev 3
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Notes
Alternate functions
I B -
(3)
I/O FTf
I/O FTf -
S - -
S - -
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Pinouts and pin description
Pin functions
Additional
functions
Boot memory selection
I2C1_SCL,
TIM16_CH1
I2C1_SDA,
IR_OUT,
TIM17_CH1,
EVENTOUT
Ground
Digital power supply
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