diff --git a/Libraries/PeriphDrivers/Source/SYS/sys_me12.c b/Libraries/PeriphDrivers/Source/SYS/sys_me12.c
index d7db012f1e..a94212d687 100644
--- a/Libraries/PeriphDrivers/Source/SYS/sys_me12.c
+++ b/Libraries/PeriphDrivers/Source/SYS/sys_me12.c
@@ -103,7 +103,7 @@ int MXC_SYS_GetUSN(uint8_t *usn, uint8_t *checksum)
         // Set NULL Key
         MXC_AES_SetExtKey((const void *)aes_key, MXC_AES_128BITS);
 
-        uint8_t usn_copy[MXC_SYS_USN_LEN] = { 0 };
+        uint8_t usn_copy[MXC_SYS_USN_CHECKSUM_LEN] = { 0 };
         memcpy(usn_copy, usn, MXC_SYS_USN_LEN);
         // Compute Checksum
         mxc_aes_req_t aes_req;
diff --git a/Libraries/PeriphDrivers/Source/SYS/sys_me15.c b/Libraries/PeriphDrivers/Source/SYS/sys_me15.c
index dd4ad6874d..eb7da8daec 100644
--- a/Libraries/PeriphDrivers/Source/SYS/sys_me15.c
+++ b/Libraries/PeriphDrivers/Source/SYS/sys_me15.c
@@ -110,7 +110,7 @@ int MXC_SYS_GetUSN(uint8_t *usn, uint8_t *checksum)
         // Set NULL Key
         MXC_AES_SetExtKey((const void *)aes_key, MXC_AES_128BITS);
 
-        uint8_t usn_copy[MXC_SYS_USN_LEN] = { 0 };
+        uint8_t usn_copy[MXC_SYS_USN_CHECKSUM_LEN] = { 0 };
         memcpy(usn_copy, usn, MXC_SYS_USN_LEN);
 
         // Compute Checksum
diff --git a/Libraries/PeriphDrivers/Source/SYS/sys_me17.c b/Libraries/PeriphDrivers/Source/SYS/sys_me17.c
index ff2d5c9288..0b7ce1ac92 100644
--- a/Libraries/PeriphDrivers/Source/SYS/sys_me17.c
+++ b/Libraries/PeriphDrivers/Source/SYS/sys_me17.c
@@ -105,7 +105,7 @@ int MXC_SYS_GetUSN(uint8_t *usn, uint8_t *checksum)
         // Set NULL Key
         MXC_AES_SetExtKey((const void *)aes_key, MXC_AES_128BITS);
 
-        uint8_t usn_copy[MXC_SYS_USN_LEN] = { 0 };
+        uint8_t usn_copy[MXC_SYS_USN_CHECKSUM_LEN] = { 0 };
         memcpy(usn_copy, usn, MXC_SYS_USN_LEN);
 
         // Compute Checksum