OpenRAM/compiler/bitcells/replica_bitcell_1w_1r.py

33 lines
1.5 KiB
Python

import design
import debug
import utils
from tech import GDS,layer,drc,parameter
class replica_bitcell_1w_1r(design.design):
"""
A single bit cell which is forced to store a 0.
This module implements the single memory cell used in the design. It
is a hand-made cell, so the layout and netlist should be available in
the technology library. """
pin_names = ["bl0", "br0", "bl1", "br1", "wl0", "wl1", "vdd", "gnd"]
(width,height) = utils.get_libcell_size("replica_cell_1w_1r", GDS["unit"], layer["boundary"])
pin_map = utils.get_libcell_pins(pin_names, "replica_cell_1w_1r", GDS["unit"])
def __init__(self, name=""):
# Ignore the name argument
design.design.__init__(self, "replica_cell_1w_1r")
debug.info(2, "Create replica bitcell 1w+1r object")
self.width = replica_bitcell_1w_1r.width
self.height = replica_bitcell_1w_1r.height
self.pin_map = replica_bitcell_1w_1r.pin_map
def get_wl_cin(self):
"""Return the relative capacitance of the access transistor gates"""
#This is a handmade cell so the value must be entered in the tech.py file or estimated.
#Calculated in the tech file by summing the widths of all the related gates and dividing by the minimum width.
#FIXME: sizing is not accurate with the handmade cell. Change once cell widths are fixed.
access_tx_cin = parameter["6T_access_size"]/drc["minwidth_tx"]
return 2*access_tx_cin