# See LICENSE for licensing information. # # Copyright (c) 2016-2019 Regents of the University of California # All rights reserved. # from bitcell_base_array import bitcell_base_array from sram_factory import factory from globals import OPTS from tech import cell_properties class col_cap_array(bitcell_base_array): """ Generate a dummy row/column for the replica array. """ def __init__(self, cols, rows, column_offset=0, mirror=0, name=""): super().__init__(cols, rows, name, column_offset) self.mirror = mirror self.create_netlist() if not OPTS.netlist_only: self.create_layout() def create_netlist(self): """ Create and connect the netlist """ self.add_modules() self.add_pins() self.create_instances() def create_layout(self): self.place_array("dummy_r{0}_c{1}", self.mirror) self.add_layout_pins() self.add_boundary() self.DRC_LVS() def add_modules(self): """ Add the modules used in this design """ self.dummy_cell = factory.create(module_type="col_cap_{}".format(OPTS.bitcell)) self.add_mod(self.dummy_cell) self.cell = factory.create(module_type="bitcell") def create_instances(self): """ Create the module instances used in this design """ self.cell_inst = {} for col in range(self.column_size): for row in range(self.row_size): name = "bit_r{0}_c{1}".format(row, col) self.cell_inst[row,col]=self.add_inst(name=name, mod=self.dummy_cell) self.connect_inst(self.get_bitcell_pins(col, row)) def get_bitcell_pins(self, col, row): """ Creates a list of connections in the bitcell, indexed by column and row, for instance use in bitcell_array """ pin_name = cell_properties.bitcell.cell_1rw1r.pin bitcell_pins = ["{0}_{1}".format(pin_name.bl0, col), "{0}_{1}".format(pin_name.br0, col), "{0}_{1}".format(pin_name.bl1, col), "{0}_{1}".format(pin_name.br1, col), "vdd"] return bitcell_pins def add_layout_pins(self): """ Add the layout pins """ column_list = self.cell.get_all_bitline_names() for col in range(self.column_size): for cell_column in column_list: bl_pin = self.cell_inst[0,col].get_pin(cell_column) self.add_layout_pin(text=cell_column+"_{0}".format(col), layer=bl_pin.layer, offset=bl_pin.ll().scale(1,0), width=bl_pin.width(), height=self.height) # Add vdd/gnd via stacks for row in range(self.row_size): for col in range(self.column_size): inst = self.cell_inst[row,col] for pin_name in ["vdd", "gnd"]: for pin in inst.get_pins(pin_name): self.add_power_pin(name=pin.name, loc=pin.center(), start_layer=pin.layer) # def input_load(self): # wl_wire = self.gen_wl_wire() # return wl_wire.return_input_cap() # # def get_wordline_cin(self): # """Get the relative input capacitance from the wordline connections in all the bitcell""" # #A single wordline is connected to all the bitcells in a single row meaning the capacitance depends on the # of columns # bitcell_wl_cin = self.cell.get_wl_cin() # total_cin = bitcell_wl_cin * self.column_size # return total_cin