Hi Jingfang,
ADC2 and ADC1-A,B clocking frequency is 6 MHz.
Regarding the sampling frequency, in normal mode, it is driven by the MCU. When a start of conversion command is sent on SPI or TPL bus, then the device will sample all CTx and ANx channels.
In cyclic acquisition mode, it depends on the content of the CYCLIC_TIMER bits in the SYS_CFG1 register.
Best regards,
Tomas
