mirror of https://github.com/VLSIDA/OpenRAM.git
547 lines
28 KiB
Python
547 lines
28 KiB
Python
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import design
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import debug
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from tech import drc, parameter, spice
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from vector import vector
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import contact
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from math import ceil
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from ptx import ptx
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from globals import OPTS
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class pbitcell(design.design):
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"""
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This module implements a parametrically sized multi-port bitcell.
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"""
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def __init__(self):
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name = "pbitcell"
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design.design.__init__(self, name)
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debug.info(2, "create a multi-port bitcell")
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self.num_write = 2
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self.num_read = 2
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self.create_layout()
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self.DRC_LVS()
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def add_pins(self):
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self.add_pin("WROW")
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self.add_pin("WBL")
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self.add_pin("WBL_bar")
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for k in range(0,self.num_read):
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self.add_pin("RROW{}".format(k))
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self.add_pin("RBL{}".format(k))
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self.add_pin("RBL_bar{}".format(k))
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self.add_pin("vdd")
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self.add_pin("gnd")
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def create_layout(self):
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self.create_ptx()
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self.add_storage()
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self.add_rails()
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self.add_write_transistors()
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self.add_read_transistors()
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self.extend_well()
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#self.add_fail()
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def create_ptx(self):
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"""
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Create ptx all transistors. Also define measurements to be used throughout bitcell.
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"""
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self.i_nmos = ptx(width=2.3*parameter["min_tx_size"],
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tx_type="nmos",
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connect_active=True,
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connect_poly=True)
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self.add_mod(self.i_nmos)
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self.i_pmos = ptx(width=parameter["min_tx_size"],
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tx_type="pmos",
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connect_active=True,
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connect_poly=True)
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self.add_mod(self.i_pmos)
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# create ptx for write transitors
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self.w_nmos = ptx(width=1.5*parameter["min_tx_size"],
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tx_type="nmos",
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connect_active=True,
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connect_poly=True)
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self.add_mod(self.w_nmos)
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# create ptx for read transistors
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self.r_nmos = ptx(width=parameter["min_tx_size"],
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tx_type="nmos",
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connect_active=True,
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connect_poly=True)
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self.add_mod(self.r_nmos)
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# determine metal contact extentions
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self.in_ex = 0.5*(self.i_nmos.active_contact.height - self.i_nmos.active_height)
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self.ip_ex = 0.5*(self.i_pmos.active_contact.height - self.i_pmos.active_height)
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self.w_ex = 0.5*(self.w_nmos.active_contact.height - self.w_nmos.active_height)
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self.r_ex = 0.5*(self.r_nmos.active_contact.height - self.r_nmos.active_height)
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# determine global measurements
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spacer = 5*drc["minwidth_metal2"] + self.w_ex + self.r_ex
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self.w_tile_width = 3*parameter["min_tx_size"] + self.w_nmos.active_height
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self.r_tile_width = 3*parameter["min_tx_size"] + self.r_nmos.active_height
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self.inv_gap = 5*contact.poly.width
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self.leftmost_xpos = -(self.i_nmos.active_width + 1.5*parameter["min_tx_size"] + drc["well_enclosure_active"]) \
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- self.num_write*(3*parameter["min_tx_size"] + self.w_nmos.active_height) \
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- (self.num_read-1)*(3*parameter["min_tx_size"] + self.r_nmos.active_height) - spacer - self.r_nmos.active_height
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self.botmost_ypos = -2*drc["minwidth_metal1"] - self.num_write*2*drc["minwidth_metal2"] - self.num_read*2*drc["minwidth_metal2"]
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self.topmost_ypos = self.inv_gap + self.i_nmos.active_height + self.i_pmos.active_height + drc["poly_extend_active"] + 2*drc["minwidth_metal1"]
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self.cell_width = -2*self.leftmost_xpos
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self.cell_height = self.topmost_ypos - self.botmost_ypos
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def add_rails(self):
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"""
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Adds rails for vdd and gnd.
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"""
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self.gnd_position = vector(self.leftmost_xpos, -2*drc["minwidth_metal1"])
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self.gnd = self.add_layout_pin(text="gnd",
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layer="metal1",
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offset=self.gnd_position,
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width=self.cell_width,
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height=drc["minwidth_metal1"])
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self.vdd_position = vector(self.leftmost_xpos, self.i_pmosL.get_pin("S").uc().y + drc["minwidth_metal1"])
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self.vdd = self.add_layout_pin(text="vdd",
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layer="metal1",
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offset=self.vdd_position,
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width=self.cell_width,
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height=drc["minwidth_metal1"])
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# connect sources to rails
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# connect nmos to gnd
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i_nmosL_source = self.i_nmosL.get_pin("S").bc()
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gnd_posL = vector(self.i_nmosL.get_pin("S").bc().x, self.gnd_position.y + drc["minwidth_metal1"])
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self.add_path("metal1", [i_nmosL_source, gnd_posL])
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i_nmosR_drain = self.i_nmosR.get_pin("D").bc()
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gnd_posR = vector(self.i_nmosR.get_pin("D").bc().x, self.gnd_position.y + drc["minwidth_metal1"])
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self.add_path("metal1", [i_nmosR_drain, gnd_posR])
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# connect pmos to vdd
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i_pmosL_source = self.i_pmosL.get_pin("S").uc()
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vdd_posL = vector(self.i_nmosL.get_pin("S").uc().x, self.vdd_position.y)
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self.add_path("metal1", [i_pmosL_source, vdd_posL])
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i_pmosR_drain = self.i_pmosR.get_pin("D").uc()
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vdd_posR = vector(self.i_nmosR.get_pin("D").uc().x, self.vdd_position.y)
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self.add_path("metal1", [i_pmosR_drain, vdd_posR])
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def add_storage(self):
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"""
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Creates the crossed coupled inverters that act as storage for the bitcell.
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"""
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# calculate offsets
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lit_xpos = -(self.i_nmos.active_width + 1.5*parameter["min_tx_size"])
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rit_xpos = 1.5*parameter["min_tx_size"]
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it_ypos = self.inv_gap + self.i_nmos.active_height
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# create active
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self.i_nmosL = self.add_inst(name="i_nmosL",
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mod=self.i_nmos,
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offset=[lit_xpos,0])
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self.connect_inst(["IR", "IL", "gnd", "gnd"])
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self.i_nmosR = self.add_inst(name="i_nmosR",
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mod=self.i_nmos,
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offset=[rit_xpos,0])
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self.connect_inst(["IL", "IR", "gnd", "gnd"])
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self.i_pmosL = self.add_inst(name="i_pmosL",
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mod=self.i_pmos,
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offset=[lit_xpos, it_ypos])
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self.connect_inst(["IL", "IR", "vdd", "vdd"])
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self.i_pmosR = self.add_inst(name="i_pmosR",
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mod=self.i_pmos,
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offset=[rit_xpos, it_ypos])
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self.connect_inst(["IL", "IR", "vdd", "vdd"])
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# connect poly for inverters
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i_nmosL_poly = self.i_nmosL.get_pin("G").uc()
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i_pmosL_poly = self.i_pmosL.get_pin("G").bc()
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self.add_path("poly", [i_nmosL_poly, i_pmosL_poly])
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i_nmosR_poly = self.i_nmosR.get_pin("G").uc()
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i_pmosR_poly = self.i_pmosR.get_pin("G").bc()
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self.add_path("poly", [i_nmosR_poly, i_pmosR_poly])
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# connect drains for inverters
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i_nmosL_drain = self.i_nmosL.get_pin("D").uc()
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i_pmosL_drain = self.i_pmosL.get_pin("D").bc()
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self.add_path("metal1", [i_nmosL_drain, i_pmosL_drain])
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i_nmosR_source = self.i_nmosR.get_pin("S").uc()
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i_pmosR_source = self.i_pmosR.get_pin("S").bc()
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self.add_path("metal1", [i_nmosR_source, i_pmosR_source])
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# add cross couple vias
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offset = vector(self.i_nmosL.get_pin("D").ur().x + contact.poly.height, self.i_nmos.active_height + 0.6*self.inv_gap)
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self.icl = self.add_contact(layers=("poly", "contact", "metal1"),
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offset=offset,
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rotate=90)
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offset = vector(self.i_nmosR.get_pin("S").ul().x, self.i_nmos.active_height + 0.2*self.inv_gap)
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self.icr = self.add_contact(layers=("poly", "contact", "metal1"),
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offset=offset,
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rotate=90)
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# connect vias to poly (cross couple)
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correct = 0.5*(self.i_nmos.active_contact.width - drc["minwidth_metal1"])
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cross_width = 0.5*self.i_nmos.active_width - 0.5*drc["minwidth_poly"] + 3*parameter["min_tx_size"] + correct
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offset = vector(self.i_nmosL.get_pin("G").ur().x, self.i_nmos.active_height + 0.2*self.inv_gap)
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self.add_rect(layer="poly",
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offset=offset,
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width=cross_width,
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height=contact.poly.width)
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offset = vector(self.i_nmosL.get_pin("D").ur().x, self.i_nmos.active_height + 0.6*self.inv_gap)
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self.add_rect(layer="poly",
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offset=offset,
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width=cross_width,
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height=contact.poly.width)
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def add_write_transistors(self):
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"""
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Define variables relevant to write transistors
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"""
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lit_xpos = -(self.i_nmos.active_width + 1.5*parameter["min_tx_size"])
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rit_xpos = 1.5*parameter["min_tx_size"]
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rot_correct = self.w_nmos.active_height
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self.w_nmosL = [None] * self.num_write
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self.w_nmosR = [None] * self.num_write
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self.wrow_positions = [None] * self.num_write
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self.wbl_positions = [None] * self.num_write
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self.wbl_bar_positions = [None] * self.num_write
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for k in range(0,self.num_write):
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"""
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Add transistors and WROW lines
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"""
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wrow_ypos = -2*drc["minwidth_metal1"] - (k+1)*2*drc["minwidth_metal2"]
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lwt_xpos = lit_xpos + rot_correct - (k+1)*self.w_tile_width
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rwt_xpos = rit_xpos + self.i_nmos.active_width + 3*parameter["min_tx_size"] + rot_correct + k*self.w_tile_width
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self.w_nmosL[k] = self.add_inst(name="w_nmosL{}".format(k),
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mod=self.w_nmos,
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offset=[lwt_xpos,0],
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rotate=90)
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self.connect_inst(["IR", "WROW{}".format(k), "WBL{}".format(k), "gnd"])
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self.w_nmosR[k] = self.add_inst(name="w_nmosR{}".format(k),
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mod=self.w_nmos,
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offset=[rwt_xpos,0],
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rotate=90)
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self.connect_inst(["IL", "WROW{}".format(k), "WBL_bar{}".format(k), "gnd"])
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# add WROW lines
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self.wrow_positions[k] = vector(self.leftmost_xpos, wrow_ypos)
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self.add_layout_pin(text="WROW{}".format(k),
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layer="metal1",
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offset=self.wrow_positions[k],
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width=self.cell_width,
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height=drc["minwidth_metal1"])
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"""
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Source/WBL/WBL_bar connections
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"""
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# connect sources to WBL and WBL_bar
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self.wbl_positions[k] = vector(lwt_xpos - drc["minwidth_metal2"],self.botmost_ypos)
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self.add_layout_pin(text="WBL{}".format(k),
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layer="metal2",
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offset=self.wbl_positions[k],
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width=drc["minwidth_metal2"],
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height=self.cell_height)
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self.wbl_bar_positions[k] = vector(rwt_xpos - rot_correct,self.botmost_ypos)
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self.add_layout_pin(text="WBL_bar{}".format(k),
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layer="metal2",
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offset=self.wbl_bar_positions[k],
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width=drc["minwidth_metal2"],
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height=self.cell_height)
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# add vias to connect source of wt to WBL and WBL_bar
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offset = self.w_nmosL[k].get_pin("S").ll() + vector(self.w_nmos.active_height, 0)
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self.add_contact(layers=("metal1", "via1", "metal2"),
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offset=offset,
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rotate=90)
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offset = self.w_nmosR[k].get_pin("S").ll() + vector(self.w_nmos.active_height, 0)
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self.add_contact(layers=("metal1", "via1", "metal2"),
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offset=offset,
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rotate=90)
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"""
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Gate/WROW connections
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"""
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# add vias to connect wt gate to WROW
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correct = vector(0.5*(drc["minwidth_metal2"] - drc["minwidth_metal1"]),0)
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offset = self.w_nmosL[k].get_pin("S").ll() - vector(drc["minwidth_metal2"] + contact.poly.width, 0)
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self.add_contact(layers=("poly", "contact", "metal1"),
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offset=offset)
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self.add_contact(layers=("metal1", "via1", "metal2"),
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offset=offset+correct)
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via_offsetL = offset + vector(0.5*contact.poly.width, 0)
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gate_offsetL = vector(offset.x + 0.5*contact.poly.width, self.w_nmosL[k].get_pin("G").ul().y)
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self.add_path("poly", [via_offsetL, gate_offsetL], width=contact.poly.width)
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self.add_path("poly", [gate_offsetL, self.w_nmosL[k].get_pin("G").lc()])
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offset = self.w_nmosR[k].get_pin("S").lr() + vector(drc["minwidth_metal2"], 0)
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self.add_contact(layers=("poly", "contact", "metal1"),
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offset=offset)
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self.add_contact(layers=("metal1", "via1", "metal2"),
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offset=offset+correct)
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via_offsetR = offset + vector(0.5*contact.poly.width, 0)
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||
|
|
gate_offsetR = vector(offset.x + 0.5*contact.poly.width, self.w_nmosR[k].get_pin("G").ur().y)
|
||
|
|
self.add_path("poly", [via_offsetR, gate_offsetR], width=contact.poly.width)
|
||
|
|
self.add_path("poly", [gate_offsetR, self.w_nmosR[k].get_pin("G").rc()])
|
||
|
|
|
||
|
|
# add vias to WROW lines
|
||
|
|
offset = vector(via_offsetL.x + contact.m1m2.height - 0.5*drc["minwidth_metal2"],self.wrow_positions[k].y)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
wrow_offset = vector(via_offsetL.x, self.wrow_positions[k].y)
|
||
|
|
self.add_path("metal2", [via_offsetL, wrow_offset])
|
||
|
|
|
||
|
|
offset = vector(via_offsetR.x + 0.5*drc["minwidth_metal2"], self.wrow_positions[k].y)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
wrow_offset = vector(via_offsetR.x, self.wrow_positions[k].y)
|
||
|
|
self.add_path("metal2", [via_offsetR, wrow_offset])
|
||
|
|
|
||
|
|
|
||
|
|
"""
|
||
|
|
Drain/Storage connections
|
||
|
|
"""
|
||
|
|
if(k == self.num_write-1):
|
||
|
|
# add vias to connect input of inverters to drain of wt
|
||
|
|
offset = vector(lit_xpos - drc["minwidth_metal1"], self.i_nmos.active_height + 0.2*self.inv_gap)
|
||
|
|
self.add_contact(layers=("poly", "contact", "metal1"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
offset = vector(rit_xpos + self.i_nmos.active_width + drc["minwidth_metal1"] + contact.poly.height, self.i_nmos.active_height + 0.2*self.inv_gap)
|
||
|
|
self.add_contact(layers=("poly", "contact", "metal1"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
# connect drains of wt to input of inverters
|
||
|
|
correct = 0.5*(contact.poly.width - drc["minwidth_metal1"])
|
||
|
|
w_nmosL_drain = self.w_nmosL[k].get_pin("D").rc()
|
||
|
|
via_offsetLB = vector(lit_xpos - drc["minwidth_metal1"] - contact.poly.height, self.w_nmosL[k].get_pin("D").rc().y)
|
||
|
|
via_offsetLT = vector(lit_xpos - drc["minwidth_metal1"] - contact.poly.height, self.i_nmos.active_height + 0.2*self.inv_gap + contact.poly.width - correct)
|
||
|
|
self.add_path("metal1", [w_nmosL_drain, via_offsetLB, via_offsetLT])
|
||
|
|
|
||
|
|
w_nmosR_drain = self.w_nmosR[k].get_pin("D").lc()
|
||
|
|
via_offsetRB = vector(rit_xpos + self.i_nmos.active_width + drc["minwidth_metal1"] + contact.poly.height, self.w_nmosR[k].get_pin("D").lc().y)
|
||
|
|
via_offsetRT = vector(rit_xpos + self.i_nmos.active_width + drc["minwidth_metal1"] + contact.poly.height, self.i_nmos.active_height + 0.2*self.inv_gap + contact.poly.width - correct)
|
||
|
|
self.add_path("metal1", [w_nmosR_drain, via_offsetRB, via_offsetRT])
|
||
|
|
|
||
|
|
via_offsetL = vector(lit_xpos - drc["minwidth_metal1"] - contact.poly.height, self.i_nmos.active_height + 0.2*self.inv_gap + 0.5*contact.poly.width)
|
||
|
|
gate_offsetL = vector(self.i_nmosL.get_pin("G").ll().x, self.i_nmos.active_height + 0.2*self.inv_gap + 0.5*contact.poly.width)
|
||
|
|
self.add_path("poly", [via_offsetL, gate_offsetL], width=contact.poly.width)
|
||
|
|
|
||
|
|
via_offsetR = vector(rit_xpos + self.i_nmos.active_width + drc["minwidth_metal1"] + contact.poly.height, self.i_nmos.active_height + 0.2*self.inv_gap + 0.5*contact.poly.width)
|
||
|
|
gate_offsetR = vector(self.i_nmosR.get_pin("G").lr().x, self.i_nmos.active_height + 0.2*self.inv_gap + 0.5*contact.poly.width)
|
||
|
|
self.add_path("poly", [via_offsetR, gate_offsetR], width=contact.poly.width)
|
||
|
|
|
||
|
|
|
||
|
|
def add_read_transistors(self):
|
||
|
|
"""
|
||
|
|
Define variables relevant to read transistors
|
||
|
|
"""
|
||
|
|
lit_xpos = -(self.i_nmos.active_width + 1.5*parameter["min_tx_size"])
|
||
|
|
rit_xpos = 1.5*parameter["min_tx_size"]
|
||
|
|
wrow_ypos = -2*drc["minwidth_metal1"] - self.num_write*2*drc["minwidth_metal2"]
|
||
|
|
lwt_xpos = lit_xpos - self.num_write*self.w_tile_width
|
||
|
|
rwt_xpos = rit_xpos + self.i_nmos.active_width + self.num_write*self.w_tile_width
|
||
|
|
|
||
|
|
rot_correct = self.r_nmos.active_height
|
||
|
|
spacer = 5*drc["minwidth_metal2"]
|
||
|
|
|
||
|
|
self.r_nmosL = [None] * self.num_read
|
||
|
|
self.r_nmosR = [None] * self.num_read
|
||
|
|
self.rrow_positions = [None] * self.num_read
|
||
|
|
self.rbl_positions = [None] * self.num_read
|
||
|
|
self.rbl_bar_positions = [None] * self.num_read
|
||
|
|
|
||
|
|
|
||
|
|
for k in range(0,self.num_read):
|
||
|
|
"""
|
||
|
|
Add transistors and RROW lines
|
||
|
|
"""
|
||
|
|
lrt_xpos = lwt_xpos - spacer - self.r_nmos.active_height + rot_correct - k*self.r_tile_width
|
||
|
|
rrt_xpos = rwt_xpos + spacer + rot_correct + k*self.r_tile_width
|
||
|
|
|
||
|
|
self.r_nmosL[k] = self.add_inst(name="r_nmosL",
|
||
|
|
mod=self.r_nmos,
|
||
|
|
offset=[lrt_xpos,0],
|
||
|
|
rotate=90)
|
||
|
|
self.connect_inst(["RROW{}".format(k), "IL", "RBL{}".format(k), "gnd"])
|
||
|
|
|
||
|
|
self.r_nmosR[k] = self.add_inst(name="r_nmosR",
|
||
|
|
mod=self.r_nmos,
|
||
|
|
offset=[rrt_xpos,0],
|
||
|
|
rotate=90)
|
||
|
|
self.connect_inst(["RROW{}".format(k), "IR", "RBL_bar{}".format(k), "gnd"])
|
||
|
|
|
||
|
|
|
||
|
|
# add RROW lines
|
||
|
|
rrow_ypos = wrow_ypos - (k+1)*2*drc["minwidth_metal2"]
|
||
|
|
self.rrow_positions[k] = vector(self.leftmost_xpos, rrow_ypos)
|
||
|
|
self.add_layout_pin(text="RROW{}".format(k),
|
||
|
|
layer="metal1",
|
||
|
|
offset=self.rrow_positions[k],
|
||
|
|
width=self.cell_width,
|
||
|
|
height=drc["minwidth_metal1"])
|
||
|
|
|
||
|
|
"""
|
||
|
|
Drain/RBL/RBL_bar connections
|
||
|
|
"""
|
||
|
|
# connect drains to RBL and RBL_bar
|
||
|
|
self.rbl_positions[k] = vector(self.r_nmosL[k].get_pin("D").rc().x + drc["minwidth_metal2"],self.botmost_ypos)
|
||
|
|
self.add_layout_pin(text="RBL{}".format(k),
|
||
|
|
layer="metal2",
|
||
|
|
offset=self.rbl_positions[k],
|
||
|
|
width=drc["minwidth_metal2"],
|
||
|
|
height=self.cell_height)
|
||
|
|
|
||
|
|
self.rbl_bar_positions[k] = vector(self.r_nmosR[k].get_pin("D").lc().x - 2*drc["minwidth_metal2"],self.botmost_ypos)
|
||
|
|
self.add_layout_pin(text="RBL_bar{}".format(k),
|
||
|
|
layer="metal2",
|
||
|
|
offset=self.rbl_bar_positions[k],
|
||
|
|
width=drc["minwidth_metal2"],
|
||
|
|
height=self.cell_height)
|
||
|
|
|
||
|
|
# add vias to connect drain of rt to RBL and RBL_bar
|
||
|
|
offset = self.r_nmosL[k].get_pin("D").ll() + vector(contact.m1m2.height, 0)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
offset = self.r_nmosR[k].get_pin("D").ll() + vector(contact.m1m2.height, 0)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
# connect drain of rt to RBL and RBL_bar
|
||
|
|
rbl_offset = vector(self.rbl_positions[k].x, self.r_nmosL[k].get_pin("D").lc().y)
|
||
|
|
self.add_path("metal2", [self.r_nmosL[k].get_pin("D").lc(), rbl_offset])
|
||
|
|
|
||
|
|
rbl_bar_offset = vector(self.rbl_bar_positions[k].x, self.r_nmosR[k].get_pin("D").rc().y)
|
||
|
|
self.add_path("metal2", [self.r_nmosR[k].get_pin("D").rc(), rbl_bar_offset])
|
||
|
|
|
||
|
|
"""
|
||
|
|
Source/RROW connections
|
||
|
|
"""
|
||
|
|
# add vias on rt sources
|
||
|
|
offset = self.r_nmosL[k].get_pin("S").ll() + vector(contact.m1m2.height, 0)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
offset = self.r_nmosR[k].get_pin("S").ll() + vector(contact.m1m2.height, 0)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
# add vias on rrows
|
||
|
|
offset = vector(self.r_nmosL[k].get_pin("S").ll().x + contact.m1m2.height, self.rrow_positions[k].y)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
offset = vector(self.r_nmosR[k].get_pin("S").ll().x + contact.m1m2.height, self.rrow_positions[k].y)
|
||
|
|
self.add_contact(layers=("metal1", "via1", "metal2"),
|
||
|
|
offset=offset,
|
||
|
|
rotate=90)
|
||
|
|
|
||
|
|
# connect sources of rt to rrows
|
||
|
|
rrow_offset = vector(self.r_nmosL[k].get_pin("S").bc().x, self.rrow_positions[k].y)
|
||
|
|
self.add_path("metal2", [self.r_nmosL[k].get_pin("S").bc(), rrow_offset])
|
||
|
|
|
||
|
|
rrow_offset = vector(self.r_nmosR[k].get_pin("S").bc().x, self.rrow_positions[k].y)
|
||
|
|
self.add_path("metal2", [self.r_nmosR[k].get_pin("S").bc(), rrow_offset])
|
||
|
|
|
||
|
|
"""
|
||
|
|
Gate/inverter connections
|
||
|
|
"""
|
||
|
|
# add vias to connect to gate of rt
|
||
|
|
offsetL = vector(self.r_nmosL[k].get_pin("D").lr().x + drc["minwidth_metal1"], self.r_nmosL[k].get_pin("G").lr().y)
|
||
|
|
self.add_contact(layers=("poly", "contact", "metal1"),
|
||
|
|
offset=offsetL)
|
||
|
|
|
||
|
|
offsetR = vector(self.r_nmosR[k].get_pin("D").ll().x - drc["minwidth_metal1"] - contact.poly.width, self.r_nmosR[k].get_pin("G").ll().y)
|
||
|
|
self.add_contact(layers=("poly", "contact", "metal1"),
|
||
|
|
offset=offsetR)
|
||
|
|
|
||
|
|
# add metal1 path between gate vias and inverter inputs
|
||
|
|
midL = vector(offsetL.x + 0.5*contact.poly.width, self.i_nmos.active_height + 0.6*self.inv_gap + 0.5*drc["minwidth_metal1"])
|
||
|
|
gate_offsetL = vector(self.i_nmosL.get_pin("D").ll().x, self.i_nmos.active_height + 0.6*self.inv_gap + 0.5*drc["minwidth_metal1"])
|
||
|
|
self.add_path("metal1", [offsetL+vector(0.5*contact.poly.width,0), midL, gate_offsetL])
|
||
|
|
|
||
|
|
midR = vector(offsetR.x + 0.5*contact.poly.width, self.i_nmos.active_height + 0.6*self.inv_gap + 0.5*drc["minwidth_metal1"])
|
||
|
|
gate_offsetR = vector(self.i_nmosR.get_pin("S").lr().x, self.i_nmos.active_height + 0.6*self.inv_gap + 0.5*drc["minwidth_metal1"])
|
||
|
|
self.add_path("metal1", [offsetR+vector(0.5*contact.poly.width,0), midR, gate_offsetR])
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
def extend_well(self):
|
||
|
|
offset = vector(self.leftmost_xpos, -2*drc["minwidth_metal1"])
|
||
|
|
well_height = self.w_nmos.well_width + 2*drc["minwidth_metal1"]
|
||
|
|
self.add_rect(layer="pwell",
|
||
|
|
offset=offset,
|
||
|
|
width=self.cell_width,
|
||
|
|
height=well_height)
|
||
|
|
|
||
|
|
lit_xpos = -(self.i_nmos.active_width + 1.5*parameter["min_tx_size"] + drc["well_enclosure_active"])
|
||
|
|
it_ypos = self.inv_gap + self.i_nmos.active_height - drc["well_enclosure_active"]
|
||
|
|
offset = [lit_xpos,it_ypos]
|
||
|
|
well_width = 2*self.i_pmos.active_width + 3*parameter["min_tx_size"] + 2*drc["well_enclosure_active"]
|
||
|
|
well_height = self.i_pmos.well_height + 2*drc["minwidth_metal1"]
|
||
|
|
self.add_rect(layer="nwell",
|
||
|
|
offset=offset,
|
||
|
|
width=well_width,
|
||
|
|
height=well_height)
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
def add_fail(self):
|
||
|
|
# for failing drc
|
||
|
|
frail_width = self.well_width = 10*drc["minwidth_tx"]
|
||
|
|
frail_height = self.rail_height = drc["minwidth_metal1"]
|
||
|
|
|
||
|
|
self.gnd_position = vector(-25*drc["minwidth_tx"], - 1.5 * drc["minwidth_metal1"] - 0.5 * frail_height) # for tiling purposes
|
||
|
|
self.add_layout_pin(text="gnd",
|
||
|
|
layer="metal1",
|
||
|
|
offset=self.gnd_position,
|
||
|
|
width=frail_width,
|
||
|
|
height=frail_height)
|
||
|
|
|
||
|
|
self.gnd_position2 = vector(-25*drc["minwidth_tx"], - 0.5 * drc["minwidth_metal1"])
|
||
|
|
self.add_layout_pin(text="gnd2",
|
||
|
|
layer="metal1",
|
||
|
|
offset=self.gnd_position2,
|
||
|
|
width=frail_width,
|
||
|
|
height=frail_height)
|