OpenRAM/compiler/sense_amp_array.py

134 lines
5.1 KiB
Python

import design
from tech import drc
from vector import vector
import debug
from globals import OPTS
class sense_amp_array(design.design):
"""
Array of sense amplifiers to read the bitlines through the column mux.
Dynamically generated sense amp array for all bitlines.
"""
def __init__(self, word_size, words_per_row):
design.design.__init__(self, "sense_amp_array")
debug.info(1, "Creating {0}".format(self.name))
c = reload(__import__(OPTS.config.sense_amp))
self.mod_sense_amp = getattr(c, OPTS.config.sense_amp)
self.sense_amp_chars = self.mod_sense_amp.chars
self.word_size = word_size
self.words_per_row = words_per_row
self.add_pins()
self.create_layout()
self.DRC_LVS()
def add_pins(self):
if (self.words_per_row == 1):
for i in range(self.word_size):
self.add_pin("bl[{0}]".format(i))
self.add_pin("br[{0}]".format(i))
else:
for i in range(self.word_size):
index = i * self.words_per_row
self.add_pin("bl_out[{0}]".format(index))
self.add_pin("br_out[{0}]".format(index))
for i in range(self.word_size):
self.add_pin("data_out[{0}]".format(i))
self.add_pin("sclk")
self.add_pin("vdd")
self.add_pin("gnd")
def create_layout(self):
self.create_sense_amp()
self.setup_layout_constants()
self.add_sense_amp()
self.connect_rails()
self.offset_all_coordinates()
def setup_layout_constants(self):
self.vdd_positions = []
self.gnd_positions = []
self.SCLK_positions = []
self.amp_positions = []
self.Data_out_positions = []
self.height = self.amp.height
self.width = self.amp.width * self.word_size * self.words_per_row
def create_sense_amp(self):
self.amp = self.mod_sense_amp("sense_amp")
self.add_mod(self.amp)
def add_sense_amp(self):
for i in range(self.word_size):
name = "sa_d{0}".format(i)
index = i * self.words_per_row
amp_position = vector(self.amp.width * index, 0)
BL_offset = amp_position + vector(self.sense_amp_chars["BL"][0], 0)
BR_offset = amp_position + vector(self.sense_amp_chars["BR"][0], 0)
self.add_inst(name=name,
mod=self.amp,
offset=amp_position)
self.amp_positions.append(amp_position)
if (self.words_per_row == 1):
self.add_label(text="bl[{0}]".format(i),
layer="metal2",
offset=BL_offset)
self.add_label(text="br[{0}]".format(i),
layer="metal2",
offset=BR_offset)
self.connect_inst(["bl[{0}]".format(i),"br[{0}]".format(i),
"data_out[{0}]".format(i),
"sclk", "vdd", "gnd"])
else:
self.add_label(text="bl_out[{0}]".format(index),
layer="metal2",
offset=BL_offset)
self.add_label(text="br_out[{0}]".format(index),
layer="metal2",
offset=BR_offset)
self.connect_inst(["bl_out[{0}]".format(index), "br_out[{0}]".format(index),
"data_out[{0}]".format(i),
"sclk", "vdd", "gnd"])
self.add_label(text="data_out[{0}]".format(i),
layer="metal2",
offset=amp_position + self.sense_amp_chars["Dout"])
self.Data_out_positions.append(amp_position + self.sense_amp_chars["Dout"])
def connect_rails(self):
base_offset = vector(0, - 0.5 * drc["minwidth_metal1"])
# add vdd rail across entire array
vdd_offset = base_offset + vector(self.sense_amp_chars["vdd"]).scale(0,1)
self.add_layout_pin(text="vdd",
layer="metal1",
offset=vdd_offset,
width=self.width,
height=drc["minwidth_metal1"])
self.vdd_positions.append(vdd_offset)
# NOTE:the gnd rails are vertical so it is not connected horizontally
# add gnd rail across entire array
gnd_offset = base_offset + vector(self.sense_amp_chars["gnd"]).scale(0,1)
self.add_layout_pin(text="gnd",
layer="metal1",
offset=gnd_offset,
width=self.width,
height=drc["minwidth_metal1"])
self.gnd_positions.append(gnd_offset)
# add sclk rail across entire array
sclk_offset = base_offset + vector(self.sense_amp_chars["SCLK"]).scale(0,1)
self.add_layout_pin(text="sclk",
layer="metal1",
offset=sclk_offset,
width=self.width,
height=drc["minwidth_metal1"])
self.SCLK_positions.append(sclk_offset)