diff --git a/compiler/base/hierarchy_design.py b/compiler/base/hierarchy_design.py
index 4f72d8f6..29624af0 100644
--- a/compiler/base/hierarchy_design.py
+++ b/compiler/base/hierarchy_design.py
@@ -21,8 +21,8 @@ class hierarchy_design(hierarchy_spice.spice, hierarchy_layout.layout):
         self.sp_file = OPTS.openram_tech + "sp_lib/" + name + ".sp"
 
         self.name = name
-        hierarchy_layout.layout.__init__(self, name)
         hierarchy_spice.spice.__init__(self, name)
+        hierarchy_layout.layout.__init__(self, name)
         
 
     def get_layout_pins(self,inst):
diff --git a/compiler/base/hierarchy_spice.py b/compiler/base/hierarchy_spice.py
index cb2799f3..93c1c041 100644
--- a/compiler/base/hierarchy_spice.py
+++ b/compiler/base/hierarchy_spice.py
@@ -28,7 +28,10 @@ class spice():
         # Spice format)
         self.conns = []
         # Keep track of any comments to add the the spice
-        self.comments = []
+        try:
+            self.commments
+        except:
+            self.comments = []
 
         self.sp_read()
 
@@ -38,7 +41,12 @@ class spice():
 
     def add_comment(self, comment):
         """ Add a comment to the spice file """
-        self.comments.append(comment)
+        try:
+            self.commments
+        except:
+            self.comments = []
+        else:
+            self.comments.append(comment)
         
     def add_pin(self, name, pin_type="INOUT"):
         """ Adds a pin to the pins list. Default type is INOUT signal. """
diff --git a/compiler/pgates/pand2.py b/compiler/pgates/pand2.py
index c2165b20..f46c0d04 100644
--- a/compiler/pgates/pand2.py
+++ b/compiler/pgates/pand2.py
@@ -11,16 +11,13 @@ class pand2(pgate.pgate):
     This is a simple buffer used for driving loads. 
     """
     def __init__(self, name, size=1, height=None):
-        self.size = size
-        
-        pgate.pgate.__init__(self, name, height)
-        debug.info(1, "Creating {}".format(self.name))
+        debug.info(1, "reating pnand2 {}".format(name))
         self.add_comment("size: {}".format(size))
         
-        self.create_netlist()
-        if not OPTS.netlist_only:        
-            self.create_layout()
-
+        self.size = size
+        
+        # Creates the netlist and layout        
+        pgate.pgate.__init__(self, name, height)
 
     def create_netlist(self):
         self.add_pins()
@@ -40,6 +37,7 @@ class pand2(pgate.pgate):
         self.place_insts()
         self.add_wires()
         self.add_layout_pins()
+        self.DRC_LVS()
         
     def add_pins(self):
         self.add_pin("A")
@@ -129,4 +127,4 @@ class pand2(pgate.pgate):
     def get_cin(self):
         """Return the relative input capacitance of a single input"""
         return self.nand.get_cin()
-        
\ No newline at end of file
+        
diff --git a/compiler/pgates/pbuf.py b/compiler/pgates/pbuf.py
index 9d73c004..02137ead 100644
--- a/compiler/pgates/pbuf.py
+++ b/compiler/pgates/pbuf.py
@@ -12,17 +12,15 @@ class pbuf(pgate.pgate):
     """
     def __init__(self, name, size=4, height=None):
         
+        debug.info(1, "creating {0} with size of {1}".format(name,size))
+        self.add_comment("size: {}".format(size))
+
         self.stage_effort = 4
         self.size = size
         self.height = height
 
+        # Creates the netlist and layout
         pgate.pgate.__init__(self, name, height)
-        debug.info(1, "creating {0} with size of {1}".format(self.name,self.size))
-        self.add_comment("size: {}".format(size))
-        
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
 
 
     def create_netlist(self):
diff --git a/compiler/pgates/pdriver.py b/compiler/pgates/pdriver.py
index 02e4355c..7a60309f 100644
--- a/compiler/pgates/pdriver.py
+++ b/compiler/pgates/pdriver.py
@@ -13,6 +13,8 @@ class pdriver(pgate.pgate):
     """
     def __init__(self, name, neg_polarity=False, fanout=0, size_list=None, height=None):
 
+        debug.info(1, "creating pdriver {}".format(name))
+
         self.stage_effort = 3
         self.height = height 
         self.neg_polarity = neg_polarity
@@ -26,16 +28,9 @@ class pdriver(pgate.pgate):
         if self.size_list and self.neg_polarity:
             debug.error("Cannot specify both size_list and neg_polarity.", -1)
  
+        # Creates the netlist and layout
         pgate.pgate.__init__(self, name, height) 
-        debug.info(1, "Creating {}".format(self.name))
         
-        self.compute_sizes()
-
-        self.add_comment("sizes: {}".format(str(self.size_list)))
-        
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
 
     def compute_sizes(self):
         # size_list specified
@@ -63,6 +58,8 @@ class pdriver(pgate.pgate):
 
 
     def create_netlist(self):
+        self.compute_sizes()
+        self.add_comment("sizes: {}".format(str(self.size_list)))
         self.add_pins()
         self.add_modules()
         self.create_insts()
@@ -75,7 +72,6 @@ class pdriver(pgate.pgate):
         self.width = self.inv_inst_list[-1].rx()
         self.height = self.inv_inst_list[0].height
         
-        self.DRC_LVS()
         
     def add_pins(self):
         self.add_pin("A")
diff --git a/compiler/pgates/pgate.py b/compiler/pgates/pgate.py
index 073efa0c..dcc474d0 100644
--- a/compiler/pgates/pgate.py
+++ b/compiler/pgates/pgate.py
@@ -21,7 +21,20 @@ class pgate(design.design):
             b = factory.create(module_type="bitcell")
             self.height = b.height
 
+        self.create_netlist()
+        if not OPTS.netlist_only:        
+            self.create_layout()
+            self.DRC_LVS()
+        
 
+    def create_netlist():
+        """ Pure virtual function """
+        debug.error("Must over-ride create_netlist.",-1)
+        
+    def create_layout():
+        """ Pure virtual function """
+        debug.error("Must over-ride create_layout.",-1)
+        
     def connect_pin_to_rail(self,inst,pin,supply):
         """ Connects a ptx pin to a supply rail. """
         source_pin = inst.get_pin(pin)
diff --git a/compiler/pgates/pinv.py b/compiler/pgates/pinv.py
index b488013d..e3ff4a37 100644
--- a/compiler/pgates/pinv.py
+++ b/compiler/pgates/pinv.py
@@ -20,28 +20,18 @@ class pinv(pgate.pgate):
     """
 
     def __init__(self, name, size=1, beta=parameter["beta"], height=None, route_output=True):
-        # We need to keep unique names because outputting to GDSII
-        # will use the last record with a given name. I.e., you will
-        # over-write a design in GDS if one has and the other doesn't
-        # have poly connected, for example.
-        pgate.pgate.__init__(self, name, height)
-        debug.info(2, "create pinv structure {0} with size of {1}".format(name, size))
+
+        debug.info(2, "creating pinv structure {0} with size of {1}".format(name, size))
         self.add_comment("size: {}".format(size))
-        
+
         self.size = size
         self.nmos_size = size
         self.pmos_size = beta*size
         self.beta = beta
         self.route_output = False
-
         
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
-
-        # for run-time, we won't check every transitor DRC/LVS independently
-        # but this may be uncommented for debug purposes
-        #self.DRC_LVS()
+        # Creates the netlist and layout
+        pgate.pgate.__init__(self, name, height)
 
     def create_netlist(self):
         """ Calls all functions related to the generation of the netlist """
diff --git a/compiler/pgates/pinvbuf.py b/compiler/pgates/pinvbuf.py
index 06936895..446d8918 100644
--- a/compiler/pgates/pinvbuf.py
+++ b/compiler/pgates/pinvbuf.py
@@ -1,18 +1,21 @@
 import debug
-import design
+import pgate
 from tech import drc
 from math import log
 from vector import vector
 from globals import OPTS
 from sram_factory import factory
 
-class pinvbuf(design.design):
+class pinvbuf(pgate.pgate):
     """
     This is a simple inverter/buffer used for driving loads. It is
     used in the column decoder for 1:2 decoding and as the clock buffer.
     """
     def __init__(self, name, size=4, height=None):
 
+        debug.info(1, "creating pinvbuf {}".format(name))
+        self.add_comment("size: {}".format(size))
+
         self.stage_effort = 4
         self.row_height = height
         # FIXME: Change the number of stages to support high drives.
@@ -23,13 +26,8 @@ class pinvbuf(design.design):
         self.size = size
         self.predriver_size = max(int(self.size/(self.stage_effort/2)),1)
 
-        design.design.__init__(self, name) 
-        debug.info(1, "Creating {}".format(self.name))
-        self.add_comment("size: {}".format(size))
-
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
+        # Creates the netlist and layout        
+        pgate.pgate.__init__(self, name) 
 
 
     def create_netlist(self):
@@ -48,7 +46,6 @@ class pinvbuf(design.design):
         
         self.offset_all_coordinates()
         
-        self.DRC_LVS()
         
     def add_pins(self):
         self.add_pin("A")
diff --git a/compiler/pgates/pnand2.py b/compiler/pgates/pnand2.py
index 168bfaf2..f6441f41 100644
--- a/compiler/pgates/pnand2.py
+++ b/compiler/pgates/pnand2.py
@@ -14,8 +14,8 @@ class pnand2(pgate.pgate):
     """
     def __init__(self, name, size=1, height=None):
         """ Creates a cell for a simple 2 input nand """
-        pgate.pgate.__init__(self, name, height)
-        debug.info(2, "create pnand2 structure {0} with size of {1}".format(name, size))
+
+        debug.info(2, "creating pnand2 structure {0} with size of {1}".format(name, size))
         self.add_comment("size: {}".format(size))
 
         self.size = size
@@ -28,9 +28,8 @@ class pnand2(pgate.pgate):
         debug.check(size==1,"Size 1 pnand2 is only supported now.")
         self.tx_mults = 1
 
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
+        # Creates the netlist and layout
+        pgate.pgate.__init__(self, name, height)
 
         
     def create_netlist(self):
diff --git a/compiler/pgates/pnand3.py b/compiler/pgates/pnand3.py
index 95d02f29..80a92f66 100644
--- a/compiler/pgates/pnand3.py
+++ b/compiler/pgates/pnand3.py
@@ -14,8 +14,8 @@ class pnand3(pgate.pgate):
     """
     def __init__(self, name, size=1, height=None):
         """ Creates a cell for a simple 3 input nand """
-        pgate.pgate.__init__(self, name, height)
-        debug.info(2, "create pnand3 structure {0} with size of {1}".format(name, size))
+
+        debug.info(2, "creating pnand3 structure {0} with size of {1}".format(name, size))
         self.add_comment("size: {}".format(size))
 
         # We have trouble pitch matching a 3x sizes to the bitcell...
@@ -30,9 +30,8 @@ class pnand3(pgate.pgate):
         debug.check(size==1,"Size 1 pnand3 is only supported now.")
         self.tx_mults = 1
 
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
+        # Creates the netlist and layout
+        pgate.pgate.__init__(self, name, height)
 
         
     def add_pins(self):
diff --git a/compiler/pgates/pnor2.py b/compiler/pgates/pnor2.py
index 125261d1..49206333 100644
--- a/compiler/pgates/pnor2.py
+++ b/compiler/pgates/pnor2.py
@@ -13,8 +13,8 @@ class pnor2(pgate.pgate):
     """
     def __init__(self, name, size=1, height=None):
         """ Creates a cell for a simple 2 input nor """
-        pgate.pgate.__init__(self, name, height)
-        debug.info(2, "create pnor2 structure {0} with size of {1}".format(name, size))
+
+        debug.info(2, "creating pnor2 structure {0} with size of {1}".format(name, size))
         self.add_comment("size: {}".format(size))
 
         self.nmos_size = size
@@ -27,9 +27,8 @@ class pnor2(pgate.pgate):
         debug.check(size==1,"Size 1 pnor2 is only supported now.")
         self.tx_mults = 1
 
-        self.create_netlist()
-        self.create_layout()
-        #self.DRC_LVS()
+        # Creates the netlist and layout
+        pgate.pgate.__init__(self, name, height)
 
         
     def add_pins(self):
@@ -38,12 +37,11 @@ class pnor2(pgate.pgate):
 
     def create_netlist(self):
         self.add_pins()
+        self.create_ptx()
+        self.setup_layout_constants()
         
     def create_layout(self):
         """ Calls all functions related to the generation of the layout """
-
-        self.create_ptx()
-        self.setup_layout_constants()
         self.add_supply_rails()
         self.add_ptx()
         self.connect_rails()
diff --git a/compiler/pgates/precharge.py b/compiler/pgates/precharge.py
index 5a7672d6..c2860ec6 100644
--- a/compiler/pgates/precharge.py
+++ b/compiler/pgates/precharge.py
@@ -12,20 +12,19 @@ class precharge(pgate.pgate):
     This module implements the precharge bitline cell used in the design.
     """
     def __init__(self, name, size=1, bitcell_bl="bl", bitcell_br="br"):
-        pgate.pgate.__init__(self, name)
-        debug.info(2, "create single precharge cell: {0}".format(name))
+
+        debug.info(2, "creating precharge cell {0}".format(name))
 
         self.bitcell = factory.create(module_type="bitcell")
-        
         self.beta = parameter["beta"]
         self.ptx_width = self.beta*parameter["min_tx_size"]
         self.width = self.bitcell.width
         self.bitcell_bl = bitcell_bl
         self.bitcell_br = bitcell_br
-
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
+        
+        # Creates the netlist and layout        
+        pgate.pgate.__init__(self, name)
+        
 
     def create_netlist(self):
         self.add_pins()
@@ -40,7 +39,6 @@ class precharge(pgate.pgate):
         self.route_vdd_rail()
         self.route_bitlines()
         self.connect_to_bitlines()
-        self.DRC_LVS()
 
     def add_pins(self):
         self.add_pin_list(["bl", "br", "en_bar", "vdd"])
diff --git a/compiler/pgates/ptristate_inv.py b/compiler/pgates/ptristate_inv.py
new file mode 100644
index 00000000..14c1f7d8
--- /dev/null
+++ b/compiler/pgates/ptristate_inv.py
@@ -0,0 +1,220 @@
+import contact
+import pgate
+import debug
+from tech import drc, parameter, spice
+from vector import vector
+from math import ceil
+from globals import OPTS
+from utils import round_to_grid
+import logical_effort
+from sram_factory import factory
+
+class ptristate_inv(pgate.pgate):
+    """
+    ptristate generates gds of a parametrically sized tristate inverter. 
+
+    There is some flexibility in the size, but we do not allow multiple fingers
+    to fit in the cell height.
+
+    """
+
+    def __init__(self, name, size=1, height=None):
+
+        debug.info(2, "creating ptristate inv {0} with size of {1}".format(name, size))
+        self.add_comment("size: {}".format(size))
+
+        # We are 2x since there are two series devices
+        self.size = 2*size
+        self.nmos_size = size
+        self.beta = parameter["beta"]
+        self.pmos_size = self.beta*size
+
+        self.nmos_width = self.nmos_size * drc("minwidth_tx")
+        self.pmos_width = self.pmos_size * drc("minwidth_tx")
+        
+        # Creates the netlist and layout
+        pgate.pgate.__init__(self, name, height)
+
+    def create_netlist(self):
+        """ Calls all functions related to the generation of the netlist """
+        self.add_pins()
+        self.add_ptx()
+        self.create_ptx()        
+        
+    def create_layout(self):
+        """ Calls all functions related to the generation of the layout """
+        self.setup_layout_constants()
+        self.route_supply_rails()
+        self.place_ptx()
+        self.add_well_contacts()
+        self.extend_wells(self.well_pos)
+        self.connect_rails()
+        self.route_inputs()
+        self.route_outputs()
+        
+    def add_pins(self):
+        """ Adds pins for spice netlist """
+        self.add_pin_list(["in", "out", "en", "en_bar", "vdd", "gnd"])
+
+
+    def setup_layout_constants(self):
+        """
+        Pre-compute some handy layout parameters.
+        """
+
+        # Compute the other pmos2 location, but determining offset to overlap the
+        # source and drain pins
+        self.overlap_offset = self.pmos.get_pin("D").ll() - self.pmos.get_pin("S").ll()
+
+        # Two PMOS devices and a well contact. Separation between each.
+        # Enclosure space on the sides.
+        self.well_width = 2*self.pmos.active_width + drc("well_enclosure_active") 
+
+        # Add an extra space because we route the output on the right of the S/D
+        self.width = self.well_width + 0.5*self.m1_space
+        # Height is an input parameter, so it is not recomputed.
+        
+        # Make sure we can put a well above and below
+        self.top_bottom_space = max(contact.well.width, contact.well.height)
+
+        
+    def add_ptx(self):
+        """ Create the PMOS and NMOS transistors. """
+        self.nmos = factory.create(module_type="ptx",
+                                   width=self.nmos_width,
+                                   mults=1,
+                                   tx_type="nmos")
+        self.add_mod(self.nmos)
+        
+        self.pmos = factory.create(module_type="ptx",
+                                   width=self.pmos_width,
+                                   mults=1,
+                                   tx_type="pmos")
+
+        self.add_mod(self.pmos)
+        
+    def route_supply_rails(self):
+        """ Add vdd/gnd rails to the top and bottom. """
+        self.add_layout_pin_rect_center(text="gnd",
+                                        layer="metal1",
+                                        offset=vector(0.5*self.width,0),
+                                        width=self.width)
+
+        self.add_layout_pin_rect_center(text="vdd",
+                                        layer="metal1",
+                                        offset=vector(0.5*self.width,self.height),
+                                        width=self.width)
+
+
+    def create_ptx(self):
+        """ 
+        Create the PMOS and NMOS netlist.
+        """
+
+        # These are the inverter PMOS/NMOS
+        self.pmos1_inst=self.add_inst(name="ptri_pmos1", mod=self.pmos)
+        self.connect_inst(["vdd", "in", "n1", "vdd"])
+        self.nmos1_inst=self.add_inst(name="ptri_nmos1", mod=self.nmos)
+        self.connect_inst(["gnd", "in", "n2", "gnd"])
+
+
+        # These are the tristate PMOS/NMOS
+        self.pmos2_inst = self.add_inst(name="ptri_pmos2", mod=self.pmos)
+        self.connect_inst(["out", "en_bar", "n1", "vdd"])
+        self.nmos2_inst=self.add_inst(name="ptri_nmos2", mod=self.nmos)
+        self.connect_inst(["out", "en", "n2", "gnd"])
+
+
+
+    def place_ptx(self):
+        """ 
+        Place PMOS and NMOS to the layout at the upper-most and lowest position
+        to provide maximum routing in channel
+        """
+
+        pmos_yoff = self.height - self.pmos.active_height - self.top_bottom_space - 0.5*contact.well.height
+        nmos_yoff = self.top_bottom_space + 0.5*contact.well.height
+
+        # Tristate transistors
+        pmos1_pos = vector(self.pmos.active_offset.x, pmos_yoff)
+        self.pmos1_inst.place(pmos1_pos)
+        nmos1_pos = vector(self.pmos.active_offset.x, nmos_yoff)
+        self.nmos1_inst.place(nmos1_pos)
+
+        # Inverter transistors
+        self.pmos2_pos = pmos1_pos + self.overlap_offset
+        self.pmos2_inst.place(self.pmos2_pos)
+        self.nmos2_pos = nmos1_pos + self.overlap_offset
+        self.nmos2_inst.place(self.nmos2_pos)
+
+        # Output position will be in between the PMOS and NMOS        
+        self.output_pos = vector(0, 0.5*(pmos_yoff + nmos_yoff + self.nmos.height))
+        
+        # This will help with the wells 
+        self.well_pos = vector(0,self.nmos1_inst.uy())
+
+
+    def route_inputs(self):
+        """ Route the gates """
+        
+        self.route_input_gate(self.pmos1_inst, self.nmos1_inst, self.output_pos.y, "in", position="farleft")
+        self.route_single_gate(self.pmos2_inst, "en_bar", position="left")
+        self.route_single_gate(self.nmos2_inst, "en", position="left")
+
+
+    def route_outputs(self):
+        """ Route the output (drains) together. """
+
+        nmos_drain_pin = self.nmos2_inst.get_pin("D")
+        pmos_drain_pin = self.pmos2_inst.get_pin("D")
+
+        nmos_drain_pos = nmos_drain_pin.lr()
+        pmos_drain_pos = pmos_drain_pin.ur()
+
+        self.add_layout_pin(text="out",
+                            layer="metal1",
+                            offset=nmos_drain_pos,
+                            height=pmos_drain_pos.y-nmos_drain_pos.y)
+
+
+    def add_well_contacts(self):
+        """ Add n/p well taps to the layout and connect to supplies AFTER the wells are created """
+
+        layer_stack = ("active", "contact", "metal1")
+
+        drain_pos = self.nmos1_inst.get_pin("S").center()
+        vdd_pos = self.get_pin("vdd").center()
+        self.nwell_contact=self.add_via_center(layers=layer_stack,
+                                               offset=vector(drain_pos.x,vdd_pos.y),
+                                               implant_type="n",
+                                               well_type="n")
+
+        gnd_pos = self.get_pin("gnd").center()
+        self.pwell_contact=self.add_via_center(layers=layer_stack,
+                                               offset=vector(drain_pos.x,gnd_pos.y),
+                                               implant_type="p",
+                                               well_type="p")
+
+        
+
+    def connect_rails(self):
+        """ Connect the nmos and pmos to its respective power rails """
+
+        self.connect_pin_to_rail(self.nmos1_inst,"S","gnd")
+        self.connect_pin_to_rail(self.pmos1_inst,"S","vdd")
+        
+
+    def analytical_delay(self, corner, slew, load=0.0):
+        from tech import spice
+        r = spice["min_tx_r"]
+        c_para = spice["min_tx_drain_c"]
+        return self.cal_delay_with_rc(corner, r = r, c =  c_para+load, slew = slew)
+        
+    def analytical_power(self, corner, load):
+        """Returns dynamic and leakage power. Results in nW"""
+        #Power in this module currently not defined. Returns 0 nW (leakage and dynamic).
+        total_power = self.return_power() 
+        return total_power
+
+    def input_load(self):
+        return 9*spice["min_tx_gate_c"]
diff --git a/compiler/pgates/ptx.py b/compiler/pgates/ptx.py
index 36fda7a0..c0686bbb 100644
--- a/compiler/pgates/ptx.py
+++ b/compiler/pgates/ptx.py
@@ -28,9 +28,7 @@ class ptx(design.design):
             name += "_c{}".format(num_contacts)
         # replace periods with underscore for newer spice compatibility
         name=name.replace('.','_')
-
-        design.design.__init__(self, name)
-        debug.info(3, "create ptx2 structure {0}".format(name))
+        debug.info(3, "creating ptx {0}".format(name))
 
         self.tx_type = tx_type
         self.mults = mults
@@ -39,6 +37,9 @@ class ptx(design.design):
         self.connect_poly = connect_poly
         self.num_contacts = num_contacts
 
+        # Do NOT create the netlist and layout (not a pgate)
+        design.design.__init__(self, name)
+
         self.create_netlist()
         # We must always create ptx layout for pbitcell
         # some transistor sizes in other netlist depend on pbitcell
diff --git a/compiler/pgates/single_level_column_mux.py b/compiler/pgates/single_level_column_mux.py
index d652fa9f..70579cf5 100644
--- a/compiler/pgates/single_level_column_mux.py
+++ b/compiler/pgates/single_level_column_mux.py
@@ -1,4 +1,4 @@
-import design
+import pgate
 import debug
 from tech import drc
 from vector import vector
@@ -7,7 +7,7 @@ from globals import OPTS
 from sram_factory import factory
 import logical_effort
 
-class single_level_column_mux(design.design):
+class single_level_column_mux(pgate.gate):
     """
     This module implements the columnmux bitline cell used in the design.
     Creates a single columnmux cell with the given integer size relative
@@ -15,18 +15,14 @@ class single_level_column_mux(design.design):
     Column-mux transistors driven by the decoder must be sized for optimal speed
     """
     def __init__(self, name, tx_size=8, bitcell_bl="bl", bitcell_br="br"):
+        
+        debug.info(2, "creating single column mux cell: {0}".format(name))
 
         self.tx_size = int(tx_size)
-
-        design.design.__init__(self, name)
-        debug.info(2, "create single column mux cell: {0}".format(name))
-
         self.bitcell_bl = bitcell_bl
         self.bitcell_br = bitcell_br
         
-        self.create_netlist()
-        if not OPTS.netlist_only:
-            self.create_layout()
+        pgate.pgate.__init__(self, name)
 
     def create_netlist(self):
         self.add_modules()