diff --git a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L443xC/TOOLCHAIN_ARM/stm32l443xc.sct b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L443xC/TOOLCHAIN_ARM/stm32l443xc.sct
index 2772062..44c4549 100644
--- a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L443xC/TOOLCHAIN_ARM/stm32l443xc.sct
+++ b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L443xC/TOOLCHAIN_ARM/stm32l443xc.sct
@@ -102,7 +102,7 @@
    .ANY (+RW +ZI)
   }
 
-  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE+MBED_IRAM2_START-AlignExpr(ImageLimit(RW_IRAM1), 16))  {
+  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE-(AlignExpr(ImageLimit(RW_IRAM1), 16)-MBED_RAM_START))  {
   }
 
   RW_IRAM2  MBED_IRAM2_START  MBED_IRAM2_SIZE  {
diff --git a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L452xE/TOOLCHAIN_ARM/stm32l452xe.sct b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L452xE/TOOLCHAIN_ARM/stm32l452xe.sct
index c37d65d..f1b1df2 100644
--- a/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L452xE/TOOLCHAIN_ARM/stm32l452xe.sct
+++ b/targets/TARGET_STM/TARGET_STM32L4/TARGET_STM32L452xE/TOOLCHAIN_ARM/stm32l452xe.sct
@@ -68,7 +68,7 @@
    .ANY (+RW +ZI)
   }
 
-  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE+MBED_IRAM2_START-AlignExpr(ImageLimit(RW_IRAM1), 16))  { ; Heap growing up
+  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE-(AlignExpr(ImageLimit(RW_IRAM1), 16)-MBED_RAM_START))  { ; Heap growing up
   }
 
   RW_IRAM2  MBED_IRAM2_START  MBED_IRAM2_SIZE  {