diff --git a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L4R5xI/device/us_ticker_data.h b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L4R5xI/device/us_ticker_data.h
index 2812efc759..cb7f2bb9a9 100644
--- a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L4R5xI/device/us_ticker_data.h
+++ b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L4R5xI/device/us_ticker_data.h
@@ -27,6 +27,7 @@ extern "C" {
 #define TIM_MST      TIM5
 #define TIM_MST_IRQ  TIM5_IRQn
 #define TIM_MST_RCC  __HAL_RCC_TIM5_CLK_ENABLE()
+#define TIM_MST_DBGMCU_FREEZE  __HAL_DBGMCU_FREEZE_TIM5()
 
 #define TIM_MST_RESET_ON   __HAL_RCC_TIM5_FORCE_RESET()
 #define TIM_MST_RESET_OFF  __HAL_RCC_TIM5_RELEASE_RESET()