| * Transistor Vth and I-V characteristic |
| .option scale=1E-6 |
| |
| * Include SkyWater sky130 device models |
| .include "../sky130_fd_pr__rf_nfet_01v8_lvt_aF06W0p84L0p15.spice" |
| .lib "../../../models/sky130.lib.spice" tt |
| |
| * Gate bias |
| Rg 1 2 680 |
| X1 3 2 0 0 sky130_fd_pr__rf_nfet_01v8_lvt_aF06W0p84L0p15 |
| Rd 3 4 100 |
| |
| * DC source for current measure |
| Vid 5 4 DC 0V |
| Vgb 1 0 DC 0V |
| Vdd 5 0 DC 3.3V |
| |
| .control |
| * Sweep Vds from 0 to 1.8V |
| dc Vdd 0 1.8 0.01 Vgb 0 1.2 0.01 |
| wrdata sky130_fd_pr__rf_nfet_01v8_lvt_aF06W0p84L0p15__iv.data Vid#branch V(1) V(3) |
| |
| * Sweep Vgs from 0 to 1.2V |
| dc Vgb 0 1.2 0.01 |
| # Find threshold |
| let ih=Vid#branch[98] |
| let il=Vid#branch[85] |
| let vh=V(2)[98] |
| let vl=V(2)[85] |
| let vth=((vl - vh) / (ih - il)) * ih + vh |
| echo threshold voltage |
| print vth |
| quit |
| .endc |
| .end |
