diff --git a/tests/unittest/ModelConfig/golden/model_config.negative.ppdb.json b/tests/unittest/ModelConfig/golden/model_config.negative.ppdb.json
index 4d96688c2..566c7a53b 100644
--- a/tests/unittest/ModelConfig/golden/model_config.negative.ppdb.json
+++ b/tests/unittest/ModelConfig/golden/model_config.negative.ppdb.json
@@ -2888,6 +2888,8 @@
         "O_P" : "dout30_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "pre_primitive" : "",
       "post_primitives" : [
diff --git a/tests/unittest/ModelConfig/golden/model_config.ppdb.json b/tests/unittest/ModelConfig/golden/model_config.ppdb.json
index c9af1463a..8e567012b 100644
--- a/tests/unittest/ModelConfig/golden/model_config.ppdb.json
+++ b/tests/unittest/ModelConfig/golden/model_config.ppdb.json
@@ -1894,6 +1894,8 @@
         "O_P" : "dout_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "pre_primitive" : "",
       "post_primitives" : [
@@ -1988,6 +1990,8 @@
         "O_P" : "dout_osc_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "pre_primitive" : "",
       "post_primitives" : [
diff --git a/tests/unittest/ModelConfig/model_config_netlist.negative.ppdb.json b/tests/unittest/ModelConfig/model_config_netlist.negative.ppdb.json
index f97676843..fe8a7e9e3 100644
--- a/tests/unittest/ModelConfig/model_config_netlist.negative.ppdb.json
+++ b/tests/unittest/ModelConfig/model_config_netlist.negative.ppdb.json
@@ -147,6 +147,8 @@
     "    Get important connection of cell \\O_BUF_DS \\o_buf_ds",
     "      Cell port \\O_N is connected to output port \\dout30_n",
     "      Cell port \\O_P is connected to output port \\dout30_p",
+    "        Parameter \\DIFFERENTIAL_TERMINATION: \"TRUE\"",
+    "        Parameter \\IOSTANDARD: \"DEFAULT\"",
     "        Data Width: -2",
     "  Trace \\I_BUF --> \\CLK_BUF",
     "    Try \\I_BUF $ibuf$top.$ibuf_clk00 out connection: $ibuf_clk00 -> \\clk_buf00",
@@ -2771,6 +2773,8 @@
         "O_P" : "dout30_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "flags" : [
         "O_BUF_DS"
diff --git a/tests/unittest/ModelConfig/model_config_netlist.ppdb.json b/tests/unittest/ModelConfig/model_config_netlist.ppdb.json
index bc47ae083..0bcb2839b 100644
--- a/tests/unittest/ModelConfig/model_config_netlist.ppdb.json
+++ b/tests/unittest/ModelConfig/model_config_netlist.ppdb.json
@@ -111,10 +111,14 @@
     "    Get important connection of cell \\O_BUF_DS \\o_buf_ds",
     "      Cell port \\O_N is connected to output port \\dout_n",
     "      Cell port \\O_P is connected to output port \\dout_p",
+    "        Parameter \\DIFFERENTIAL_TERMINATION: \"TRUE\"",
+    "        Parameter \\IOSTANDARD: \"DEFAULT\"",
     "        Data Width: -2",
     "    Get important connection of cell \\O_BUF_DS \\o_buf_ds_osc",
     "      Cell port \\O_N is connected to output port \\dout_osc_n",
     "      Cell port \\O_P is connected to output port \\dout_osc_p",
+    "        Parameter \\DIFFERENTIAL_TERMINATION: \"TRUE\"",
+    "        Parameter \\IOSTANDARD: \"DEFAULT\"",
     "        Data Width: -2",
     "  Trace \\I_BUF --> \\CLK_BUF",
     "    Try \\I_BUF $ibuf$top.$ibuf_clk0 out connection: $ibuf_clk0 -> $clkbuf$top.$ibuf_clk0",
@@ -1629,6 +1633,8 @@
         "O_P" : "dout_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "flags" : [
         "O_BUF_DS"
@@ -1701,6 +1707,8 @@
         "O_P" : "dout_osc_p"
       },
       "parameters" : {
+        "DIFFERENTIAL_TERMINATION" : "TRUE",
+        "IOSTANDARD" : "DEFAULT"
       },
       "flags" : [
         "O_BUF_DS"