diff --git a/compiler/base/hierarchy_spice.py b/compiler/base/hierarchy_spice.py
index ee7aeced..539d1a8c 100644
--- a/compiler/base/hierarchy_spice.py
+++ b/compiler/base/hierarchy_spice.py
@@ -429,7 +429,7 @@ class spice():
         c_wire = self.module_wire_c()
         r_wire = self.module_wire_r()
         # Calculate tau with provided output load then calc delay
-        tf = rd*(c_intrinsic+c_load+c_wire)+r_wire*(c_load+c_load/2)
+        tf = rd*(c_intrinsic+c_load+c_wire)+r_wire*(c_load+c_wire/2)
         this_delay = self.horowitz(inrisetime, tf, 0.5, 0.5, True)
         inrisetime = this_delay / (1.0 - 0.5)
         return delay_data(this_delay, inrisetime)
diff --git a/compiler/custom/sense_amp.py b/compiler/custom/sense_amp.py
index 4064cc89..71e86c98 100644
--- a/compiler/custom/sense_amp.py
+++ b/compiler/custom/sense_amp.py
@@ -82,9 +82,9 @@ class sense_amp(design.design):
 
     def get_on_resistance(self):
         """On resistance of pinv, defined by single nmos"""
-        is_nchannel = False
+        is_nchannel = True
         stack = 1
-        is_cell = False
+        is_cell = False 
         return self.tr_r_on(parameter["sa_inv_nmos_size"], is_nchannel, stack, is_cell)    
         
     def get_input_capacitance(self):