* Capacitor (4 terminal w/separate shield) value test | |
.param TEMP=27 | |
* Include SkyWater sky130 device models | |
.lib "../../../models/sky130.lib.spice" tt | |
.param freq = 1Meg | |
.csparam freq = {freq} | |
* Resistor bridge with capacitance | |
V1 N2 0 1.8 | |
IAC N3 N4 dc 0 ac 1 | |
X1 N3 N4 0 0 sky130_fd_pr__cap_vpp_11p5x11p7_l1m1m2m3_shieldpom4 | |
* C34 N3 N4 50E-15 | |
R1 N3 0 1.1Meg | |
R2 N4 0 1.2Meg | |
R3 N2 N3 1.3Meg | |
R4 N2 N4 1.4Meg | |
.ac lin 1 {freq} {freq} | |
.control | |
run | |
echo capacitance | |
print imag(1/v(N4,N3))/2/PI/freq | |
quit | |
.endc | |
.end |