| * Copyright 2020 The SkyWater PDK Authors |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * https://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| |
| *********************** "sky130_fd_bd_sram__openram_write_driver" ****************************** |
| |
| .SUBCKT sky130_fd_bd_sram__openram_write_driver DIN BL BR EN VDD GND |
| |
| **** Inverter to conver Data_in to data_in_bar ****** |
| * din_bar = inv(DIN) |
| M_1 din_bar DIN GND GND nshort W=0.36 L=0.15 m=1 mult=1 |
| M_2 din_bar DIN VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| |
| **** 2input nand gate follwed by inverter to drive BL ****** |
| * din_bar_gated = nand(EN, DIN) |
| M_3 din_bar_gated EN net_7 GND nshort W=0.55 L=0.15 m=1 mult=1 |
| M_4 net_7 DIN GND GND nshort W=0.55 L=0.15 m=1 mult=1 |
| M_5 din_bar_gated EN VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| M_6 din_bar_gated DIN VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| * din_bar_gated_bar = inv(din_bar_gated) |
| M_7 din_bar_gated_bar din_bar_gated VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| M_8 din_bar_gated_bar din_bar_gated GND GND nshort W=0.36 L=0.15 m=1 mult=1 |
| |
| **** 2input nand gate follwed by inverter to drive BR****** |
| * din_gated = nand(EN, din_bar) |
| M_9 din_gated EN VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| M_10 din_gated EN net_8 GND nshort W=0.55 L=0.15 m=1 mult=1 |
| M_11 net_8 din_bar GND GND nshort W=0.55 L=0.15 m=1 mult=1 |
| M_12 din_gated din_bar VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| * din_gated_bar = inv(din_gated) |
| M_13 din_gated_bar din_gated VDD VDD pshort W=0.55 L=0.15 m=1 mult=1 |
| M_14 din_gated_bar din_gated GND GND nshort W=0.36 L=0.15 m=1 mult=1 |
| |
| ************************************************ |
| * pull down with EN enable |
| M_15 BL din_gated_bar GND GND nshort W=1 L=0.15 m=1 mult=1 |
| M_16 BR din_bar_gated_bar GND GND nshort W=1 L=0.15 m=1 mult=1 |
| |
| .ENDS sky130_fd_bd_sram__openram_write_driver |
