diff --git a/technology/freepdk45/tech/tech.py b/technology/freepdk45/tech/tech.py
index f719e481..fd477077 100644
--- a/technology/freepdk45/tech/tech.py
+++ b/technology/freepdk45/tech/tech.py
@@ -472,7 +472,7 @@ spice["wire_c_per_um"] = spice["wire_unit_c"]*drc["minwidth_m2"] # Unit c by m2
 spice["wire_r_per_um"] = spice["wire_unit_r"]/drc["minwidth_m2"] # Unit r per m2 width, Ohms/um units
 spice["mobility_n"] = 0.045e8   # um^2/(V*s)
 spice["V_dsat"] = 0.0938        # From CACTI 45nm tech
-spice["sa_transconductance"] = (spice["mobility_n"])*spice["cox"]*(parameter["sa_inv_nmos_size"]/_lambda_)*spice["V_dsat"]
+spice["sa_transconductance"] = (spice["mobility_n"])*spice["cox"]*(parameter["sa_inv_nmos_size"]/parameter["min_tx_size"])*spice["V_dsat"]
 ###################################################
 # Technology Tool Preferences
 ###################################################
diff --git a/technology/scn4m_subm/tech/tech.py b/technology/scn4m_subm/tech/tech.py
index bd082460..a8c44996 100644
--- a/technology/scn4m_subm/tech/tech.py
+++ b/technology/scn4m_subm/tech/tech.py
@@ -418,7 +418,7 @@ spice["wire_c_per_um"] = spice["wire_unit_c"]*drc["minwidth_m2"] # Unit c by m2
 spice["wire_r_per_um"] = spice["wire_unit_r"]/drc["minwidth_m2"] # Unit r per m2 width, Ohms/um units
 spice["mobility_n"] = 444.94e8 # um^2/(V*s)
 spice["V_dsat"] = 0.256        # From CACTI 180nm tech
-spice["sa_transconductance"] = (spice["mobility_n"])*spice["cox"]*(parameter["sa_inv_nmos_size"]/_lambda_)*spice["V_dsat"]
+spice["sa_transconductance"] = (spice["mobility_n"])*spice["cox"]*(parameter["sa_inv_nmos_size"]/parameter["min_tx_size"])*spice["V_dsat"]
 
 
 ###################################################