diff --git a/dataflow_neuro/cell_lib_async.act b/dataflow_neuro/cell_lib_async.act
index 8e54bb3..0d8cf33 100644
--- a/dataflow_neuro/cell_lib_async.act
+++ b/dataflow_neuro/cell_lib_async.act
@@ -684,6 +684,14 @@ namespace tmpl {
         }
         }
 
+        export
+        defproc A_3P_U_X4(bool? a, b, c; bool! y; bool? vdd, vss)
+        {
+        prs{
+        [keeper=0] ~a & ~b & ~c-> y+
+        }
+        }
+
         export
         defproc PULLDOWN_X4(bool? a; bool! y; bool? vdd, vss) {
             A_1N_U_X4 cell(.a = a, .y = y, .vdd = vdd, .vss = vss);