diff --git a/docs/source/arch_lang/addon_vpr_syntax.rst b/docs/source/arch_lang/addon_vpr_syntax.rst
index 3f51e005d..1e2da988f 100644
--- a/docs/source/arch_lang/addon_vpr_syntax.rst
+++ b/docs/source/arch_lang/addon_vpr_syntax.rst
@@ -37,6 +37,8 @@ Each ``<pb_type>`` should contain a ``<mode>`` that describe the physical implem
 
   .. warning:: Do NOT enable if you are not using the tileable routing resource graph generator!
 
+  .. warning:: Current through channel supports only a fixed routing channel!
+
 ``<switch_block>`` may include addition syntax to enable different connectivity for pass tracks
 
 .. option:: sub_type="<string>"