| *--------------------------------------------------------------------------- |
| * SPDX-FileCopyrightText: 2020 Efabless Corporation |
| * 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 |
| *--------------------------------------------------------------------------- |
| * Ring oscillator testbench---simple check of ring oscillator |
| * at several trim levels |
| |
| .lib "/home/tim/projects/efabless/tech/SW/sky130A/libs.tech/ngspice/sky130.lib.spice" tt |
| |
| .include "/home/tim/projects/efabless/tech/SW/sky130A/libs.ref/sky130_fd_sc_hd/spice/sky130_fd_sc_hd.spice" |
| |
| .include "ring_osc2x13.spice" |
| |
| .option TEMP=27 |
| * .option RELTOL=1.0E-1 |
| * .option RSHUNT=1.0E20 |
| |
| * Instantiate the ring oscillator |
| * Tie trims together in four sets |
| |
| X0 vdd vss clockp0 clockp1 reset trim00 trim01 trim02 trim03 trim04 trim05 trim06 |
| + trim07 trim08 trim09 trim10 trim11 trim12 trim13 trim14 trim15 trim16 trim17 |
| + trim18 trim19 trim20 trim21 trim22 trim23 trim24 trim25 ring_osc2x13 |
| |
| * Power supply (note that all logic is 1.8V here) |
| |
| V00 vdd vss PWL(0n 0.0 30n 1.8) |
| V01 vss 0 0.0 |
| |
| * Trim values (connect resistors to power or ground) |
| * divider value = 12 |
| |
| V02 trim00 gnd PULSE(0.0 1.8 40n 2n 2n 1u 2u) |
| V03 trim01 gnd PULSE(0.0 1.8 80n 2n 2n 1u 2u) |
| V04 trim02 gnd PULSE(0.0 1.8 120n 2n 2n 1u 2u) |
| V05 trim03 gnd PULSE(0.0 1.8 160n 2n 2n 1u 2u) |
| V06 trim04 gnd PULSE(0.0 1.8 200n 2n 2n 1u 2u) |
| V07 trim05 gnd PULSE(0.0 1.8 240n 2n 2n 1u 2u) |
| V08 trim06 gnd PULSE(0.0 1.8 280n 2n 2n 1u 2u) |
| V09 trim07 gnd PULSE(0.0 1.8 320n 2n 2n 1u 2u) |
| V10 trim08 gnd PULSE(0.0 1.8 360n 2n 2n 1u 2u) |
| V11 trim09 gnd PULSE(0.0 1.8 400n 2n 2n 1u 2u) |
| V12 trim10 gnd PULSE(0.0 1.8 440n 2n 2n 1u 2u) |
| V13 trim11 gnd PULSE(0.0 1.8 480n 2n 2n 1u 2u) |
| V14 trim12 gnd PULSE(0.0 1.8 520n 2n 2n 1u 2u) |
| V15 trim13 gnd PULSE(0.0 1.8 560n 2n 2n 1u 2u) |
| V16 trim14 gnd PULSE(0.0 1.8 600n 2n 2n 1u 2u) |
| V17 trim15 gnd PULSE(0.0 1.8 640n 2n 2n 1u 2u) |
| V18 trim16 gnd PULSE(0.0 1.8 680n 2n 2n 1u 2u) |
| V19 trim17 gnd PULSE(0.0 1.8 720n 2n 2n 1u 2u) |
| V20 trim18 gnd PULSE(0.0 1.8 760n 2n 2n 1u 2u) |
| V21 trim19 gnd PULSE(0.0 1.8 800n 2n 2n 1u 2u) |
| V22 trim20 gnd PULSE(0.0 1.8 840n 2n 2n 1u 2u) |
| V23 trim21 gnd PULSE(0.0 1.8 880n 2n 2n 1u 2u) |
| V24 trim22 gnd PULSE(0.0 1.8 920n 2n 2n 1u 2u) |
| V25 trim23 gnd PULSE(0.0 1.8 960n 2n 2n 1u 2u) |
| V26 trim24 gnd PULSE(0.0 1.8 800n 2n 2n 1u 2u) |
| V27 trim25 gnd PULSE(0.0 1.8 840n 2n 2n 1u 2u) |
| |
| * Reset |
| V6 reset gnd PWL(0n 1.8 8n 1.8 10n 0.0) |
| |
| * Transient analysis |
| .control |
| tran 100p 1u |
| plot V(clockp0) V(clockp1) |
| .endc |
| .end |
