I´m french, so excuse my poor english... In my mind, ADC, Timers, USART (, etc...) are alternate peripheral, and so, I don´t understand for what is use the AFIO Clock. For example, when I use a ADC, I enable the ADC Clock and have I to enable the Alternate IO Clock? I have another question: I don´t find the stabilisation time of ADC Thanks for your answers Vince