diff --git a/configs/stm32f769i-disco/include/board.h b/configs/stm32f769i-disco/include/board.h
index d09b1b67c12..545cc617414 100755
--- a/configs/stm32f769i-disco/include/board.h
+++ b/configs/stm32f769i-disco/include/board.h
@@ -205,7 +205,7 @@
 #define STM32_RCC_DCKCFGR2_CK48MSRC   RCC_DCKCFGR2_CK48MSEL_PLLSAI
 #define STM32_RCC_DCKCFGR2_SDMMCSRC   RCC_DCKCFGR2_SDMMCSEL_48MHZ
 #define STM32_RCC_DCKCFGR2_SDMMC2SRC  RCC_DCKCFGR2_SDMMC2SEL_48MHZ
-#define STM32_RCC_DCKCFGR2_DSISRC     RCC_DCKCFGR2_DSISEL_48MHZ
+#define STM32_RCC_DCKCFGR2_DSISRC     RCC_DCKCFGR2_DSISEL_PHY
 
 /* Several prescalers allow the configuration of the two AHB buses, the
  * high-speed APB (APB2) and the low-speed APB (APB1) domains. The maximum