diff --git a/doc/guide/advanced.rst b/doc/guide/advanced.rst
index 03c75ee..ff4f871 100644
--- a/doc/guide/advanced.rst
+++ b/doc/guide/advanced.rst
@@ -11,7 +11,7 @@ Resetting an FPGA
     openFPGALoader [options] -r
 
 Using negative edge for TDO's sampling
-====================================
+======================================
 
 If transaction are unstable you can try to change read edge by using