diff --git a/mcuconf_F303.h b/mcuconf_F303.h
index 33195d5..6fd5877 100644
--- a/mcuconf_F303.h
+++ b/mcuconf_F303.h
@@ -50,7 +50,7 @@
 // Set SPI1 more faster use PPRE2 max speed
 #define STM32_PPRE2                         STM32_PPRE2_DIV1
 #define STM32_MCOSEL                        STM32_MCOSEL_PLLDIV2
-#define STM32_ADC12PRES                     STM32_ADC12PRES_DIV1
+#define STM32_ADC12PRES                     STM32_ADC12PRES_DIV2
 //#define STM32_ADC34PRES                     STM32_ADC34PRES_DIV1
 #define STM32_USART1SW                      STM32_USART1SW_PCLK
 //#define STM32_USART2SW                      STM32_USART2SW_PCLK