diff --git a/stm32-metapac/build.rs b/stm32-metapac/build.rs
index 5f812130..2b3fca80 100644
--- a/stm32-metapac/build.rs
+++ b/stm32-metapac/build.rs
@@ -69,7 +69,7 @@ fn main() {
     println!(
         "cargo:rerun-if-changed={}/chips/{}.json",
         data_dir.display(),
-        chip_name
+        chip_name.to_uppercase()
     );
 
     println!("cargo:rerun-if-changed={}/registers", data_dir.display());