RING OSCILLATOR:-

	Firstly connect the circuit diagram in esim. In esim first go to new project then give project name then click ok open the schematic of the your project and using place component we can choose the components required to our circuit and place component in the schematic window and connect the circuit connections through wire as per circuit diagram and give component names and input output port names and annotate the circuit and check the ERC if there are no errors then generate netlist.to generate netlist go to spice select default format and click on generate the .cir file is generated.
For .cir file go to esim workspace and projectname and copy file and paste in the skywater130 folder.
Edit the .cir file remove all the slash and add .lib "models/sky130.lib.spice" tt and give input voltage delay time,rise time,fall time, timeperiod and pulse width and for plotting the output give plot(inputs/outputs).If any subcircuits present add .include subcircuit filename and save the file and select the file and right click go to FOSSEE and ngspice-nghdl and then bin and then click on ngspice.exe then open and run the file.

While implementing my circuit I have faced problem while running the .cir file waning:redefination of subckt sky130_fd_pr__nfet_01v8,ignored error after removing the   .lib "models/sky130.lib.spice" tt in subcircuit files output plotted

For my project first implemented the circuit and generated the netlist and copied the .cir files  to the skywater130 folder and edit the .cir files giving input and plotting and then save and run the file.the ngspice window opens and output waveform window opens.


