diff --git a/boards/az-delivery-devkit-v4.json b/boards/az-delivery-devkit-v4.json
index 45fa0a2..93237d7 100644
--- a/boards/az-delivery-devkit-v4.json
+++ b/boards/az-delivery-devkit-v4.json
@@ -28,7 +28,7 @@
   "upload": {
     "flash_size": "4MB",
     "maximum_ram_size": 532480,
-    "maximum_size": 16777216,
+    "maximum_size": 4194304,
     "require_upload_port": true,
     "speed": 460800
   },