diff --git a/src/paras.h b/src/paras.h
index e71aa9d..2c23c76 100644
--- a/src/paras.h
+++ b/src/paras.h
@@ -16,7 +16,7 @@
     PARA( vsat_max          , int    , '\0'  ,  false   , 10000 , 0  , 100000    , "max input numbers of LUT") \
     PARA( fw_inc            , int    , '\0'  ,  false   , 2     , 0  , 1000      , "max input numbers of LUT") \
     PARA( fw_max            , int    , '\0'  ,  false   , 10000 , 0  , 1000      , "max input numbers of LUT") \
-    PARA( up_inc            , int    , '\0'  ,  false   , 1     , 0  , 1000      , "max input numbers of LUT") \
+    PARA( up_inc            , int    , '\0'  ,  false   , 5     , 0  , 1000      , "max input numbers of LUT") \
     PARA( up_max            , int    , '\0'  ,  false   , 10000 , 0  , 1000      , "max input numbers of LUT") \
     PARA( max_step_coeff    , double , '\0'  ,  false   , 10.0  , 1  , 1000      , "max input numbers of LUT")
 //            name,   short-name, must-need, default, comments