diff --git a/data/registers/flash_f4.yaml b/data/registers/flash_f4.yaml
index f5d9dbd..9836d6e 100644
--- a/data/registers/flash_f4.yaml
+++ b/data/registers/flash_f4.yaml
@@ -74,7 +74,7 @@ fieldset/CR:
     - name: SNB
       description: Sector number
       bit_offset: 3
-      bit_size: 4
+      bit_size: 5
     - name: PSIZE
       description: Program size
       bit_offset: 8