APB peripheral clock enable in Sleep mode register 1
| TIM2SMEN | TIM2 timer clock enable during Sleep mode |
| TIM3SMEN | TIM3 timer clock enable during Sleep mode |
| RTCAPBSMEN | RTC APB clock enable during Sleep mode |
| WWDGSMEN | WWDG clock enable during Sleep mode |
| SPI2SMEN | SPI2 clock enable during Sleep mode |
| USART2SMEN | USART2 clock enable during Sleep mode |
| LPUART1SMEN | LPUART1 clock enable during Sleep mode |
| I2C1SMEN | I2C1 clock enable during Sleep mode |
| I2C2SMEN | I2C2 clock enable during Sleep mode |
| DBGSMEN | Debug support clock enable during Sleep mode |
| PWRSMEN | Power interface clock enable during Sleep mode |
| LPTIM2SMEN | Low Power Timer 2 clock enable during Sleep mode |
| LPTIM1SMEN | Low Power Timer 1 clock enable during Sleep mode |