| * Transistor Vth and I-V characteristic |
| |
| * Include SkyWater sky130 device models |
| .lib "../../../models/sky130.lib.spice" tt |
| |
| * Gate bias |
| Rg 1 2 680 |
| X1 3 2 5 5 sky130_fd_pr__rf_pfet_01v8_bM02W3p00L0p15 |
| Rd 3 4 100 |
| |
| * DC source for current measure |
| Vid 4 0 DC 0V |
| Vgb 5 1 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 |
| let vgs = V(5) - V(1) |
| let vds = V(5) - V(3) |
| wrdata sky130_fd_pr__rf_pfet_01v8_bM02W3p00L0p15__iv.data Vid#branch vgs vds |
| |
| * 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(5)[98] - V(2)[98] |
| let vl=V(5)[98] - V(2)[85] |
| let vth=((vl - vh) / (ih - il)) * ih + vh |
| echo threshold voltage |
| print vth |
| quit |
| .endc |
| .end |
