Ring Oscillator Circuit Design using eSIM

I first started by designing the circuit schematic in eSim.

After designing the schematic I added 4 global variables vdd, out1, out2 , out3 and then annotated my circuit.

Next, I check for any errors, having got only the global variable error (which is supposed to be deleted and continue), I generated the netlist.

Then I converted Kicad to Ngspice, then saved it as .cir file.

I created a folder named Ring inside which we had the downloaded sky130_pd_fr file and the .cir.out file.

Now I just replaced the eSim MOSFET models by their respective sky130 models.

I ran the edited .cir.out file using ngspice.

Then I ran the transient analysis to get the oscillator output using the plot function.

PROBLEMS I FACED,

1) The eSim models replaced by their respective sky130 models ad to start their naming using x, example m1, m2, m3... had to be replaced as xm1,xm2,xm3...

2) Ngspice kept showing fatal error, hence I was asked to open the .cir.out using cmd and it worked perfectly.