| *--------------------------------------------------------------------------- |
| * 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 |
| *--------------------------------------------------------------------------- |
| * Simple POR circuit for Caravel current mirror test |
| *------------------------------------------------------------------- |
| |
| .param mc_mm_switch=0 |
| .lib /usr/share/pdk/sky130A/libs.tech/ngspice/sky130.lib.spice tt |
| |
| * Note: 20 resistors of length 25um connected in series |
| Xres1 vdda vin vss sky130_fd_pr__res_xhigh_po_0p69 l=500 |
| Xres2 vin vss vss sky130_fd_pr__res_xhigh_po_0p69 l=149 |
| |
| * voltage sources at 0V for measuring current in each branch |
| |
| Vm1 vssm1 vss DC=0 |
| Vm2 vdda vddm2 DC=0 |
| Vm3 vdda vddm3 DC=0 |
| Vm4 vssm4 vss DC=0 |
| Vm5 vssm5 vss DC=0 |
| Vm6 vdda vddm6 DC=0 |
| Vm7 vdda vddm7 DC=0 |
| |
| * D G S B |
| Xm1 casc1 vin vssm1 vss sky130_fd_pr__nfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xc1 mir1 casc1 casc1 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xm2 mir1 mir1 vddm2 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=8 |
| Xm3 mir2 mir1 vddm3 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xc2 casc2 casc1 mir2 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xm4 casc2 casc2 vssm4 vss sky130_fd_pr__nfet_g5v0d10v5 w=2 l=0.8 m=7 |
| Xm5 casc3 casc2 vssm5 vss sky130_fd_pr__nfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xc3 mir3 casc3 casc3 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xm6 mir3 mir3 vddm6 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=7 |
| Xm7 mir4 mir3 vddm7 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| Xc4 vcap casc3 mir4 vdda sky130_fd_pr__pfet_g5v0d10v5 w=2 l=0.8 m=1 |
| |
| * Check branch currents in each mirror branch. |
| * 1st branch should be 240nA |
| * 2nd branch should be 30nA |
| * 3rd branch should be 4.3nA |
| * 4th branch should be 612pA |
| * |
| * Result: vin sits at 0.7590 (close to 0.7575 target) |
| * I(Vm1/2) = 202.80 nA |
| * I(Vm3/4) = 26.10 nA (should be /8) actually /7.77 |
| * I(Vm5/6) = 4.58 nA (should be /7) actually /5.70 |
| * I(Vm7) = 0.67 nA (should be /7) actually /6.80 |
| |
| *---------------------------- |
| * Testbench circuit |
| *---------------------------- |
| Vpwr vdda vss DC=3.3 |
| Rgnd vss 0 0.01 |
| Rload vcap vss 1MEG |
| *---------------------------- |
| |
| *---------------------------- |
| * Testbench control |
| *---------------------------- |
| .control |
| op |
| print V(vin) |
| print I(Vm1) |
| print I(Vm2) |
| print I(Vm3) |
| print I(Vm4) |
| print I(Vm5) |
| print I(Vm6) |
| print I(Vm7) |
| .endc |
| |
| .end |
| |
