diff --git a/targets/TARGET_Ambiq_Micro/TARGET_Apollo3/TOOLCHAIN_ARM_STD/AMA3B1KK.sct b/targets/TARGET_Ambiq_Micro/TARGET_Apollo3/TOOLCHAIN_ARM_STD/AMA3B1KK.sct
index 67fb5a5f8b..cc2bc7e7d6 100644
--- a/targets/TARGET_Ambiq_Micro/TARGET_Apollo3/TOOLCHAIN_ARM_STD/AMA3B1KK.sct
+++ b/targets/TARGET_Ambiq_Micro/TARGET_Apollo3/TOOLCHAIN_ARM_STD/AMA3B1KK.sct
@@ -56,8 +56,8 @@ LR_IROM1 MBED_APP_START MBED_APP_SIZE {
   RW_IRAM1 MBED_RAM1_START MBED_RAM1_SIZE {
    .ANY (+RW +ZI)
   }
-  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE+MBED_RAM_START-AlignExpr(ImageLimit(RW_IRAM1), 16))  {
+  ARM_LIB_HEAP  AlignExpr(+0, 16)  EMPTY  (MBED_RAM_SIZE-RAM_FIXED_SIZE+MBED_RAM1_START-AlignExpr(ImageLimit(RW_IRAM1), 16))  {
   }
-  ARM_LIB_STACK MBED_RAM1_START+MBED_RAM1_SIZE-8 EMPTY -Stack_Size { ; Stack region growing down
+  ARM_LIB_STACK MBED_RAM1_START+MBED_RAM1_SIZE EMPTY -Stack_Size { ; Stack region growing down
   }
 }