td = 62.4 psRepresentative delayUNKNOWNInspect metric contract
1 / 5 / 10 fFLoad sweepUNKNOWNInspect metric contract
3 / 5 / 7 stagesStage sweepUNKNOWNInspect metric contract
SIMULATION / SKY130_RINGOSC_001
CMOS inverter propagation delay
Propagation Delay
Use ring-oscillator transients to extract per-stage delay across stage count and load.
EXPLORE
Start with the observable.
Use this page when the simulation is the primary artifact. The linked lesson explains the concept; the linked lab keeps the visual replay surface available.
- Select a saved stage/load case and inspect the output crossing cadence.
- Compare the 1 fF, 5 fF, and 10 fF cases to see how load stretches delay.
- Use the delay extraction as the dynamic half of the inverter lesson.
RUN CARD
Conditions before conclusions.
Delay values are extracted from the saved transient sweep; the page does not submit new SPICE jobs.
Primary knobs
- Stages: 3, 5, or 7
- Load per stage: 1 fF, 5 fF, or 10 fF
- Supply: 1.8 V
- Corner: TT, temperature: 27 C
Saved outputs
- frequency
- period
- per-stage delay
- saved waveform samples
EXPORT
Download the public artifacts.
These exports are the supported public files for review. PDK files and restricted third-party material are not redistributed.
Dataset JSON
/data/sky130-ringosc-web-v1.json
Open file ->Netlist manifest
/data/sky130-ringosc-netlist-manifest-v1.json
Open file ->3-stage 5 fF netlist
/data/ringosc_3stage_5ff.spice
Open file ->METHODS
How the number was made.
Methods are written for citation discipline: the extraction rule matters as much as the plotted value.
Measure rising-edge periods at VDD/2 after startup.
Keep this method attached when reusing the figure or metric.
Use the identity td = 1 / (2 * N * f) for an N-stage odd ring.
Keep this method attached when reusing the figure or metric.
Report delay per stage, not a full cell-library characterization.
Keep this method attached when reusing the figure or metric.
Keep the stage count and load visible with every plotted point.
Keep this method attached when reusing the figure or metric.
LIMITS
What this page does not claim.
The MVP is useful because the limits are visible. These statements prevent a teaching simulation from being cited as silicon evidence.
Ring-derived delay assumes repeated stages and does not isolate rise/fall asymmetry.
Carry this boundary into any derivative note, paper draft, or slide.
Pre-layout standard-cell simulation; routing parasitics and package effects are excluded.
Carry this boundary into any derivative note, paper draft, or slide.
One TT/27 C operating point is shown; this is not a PVT characterization.
Carry this boundary into any derivative note, paper draft, or slide.
Startup perturbation and averaging choices are part of the result.
Carry this boundary into any derivative note, paper draft, or slide.
EVIDENCE
Trace the claim back to artifacts.
The evidence route remains the catalog-level browser; this page is the simulation-level reading card.
All 9 stage/load cases oscillated in the preserved evidence payload.
SKY130_RINGOSC_001
The payload records the period extraction rule and stage-delay identity.
SKY130_RINGOSC_001
Each netlist hash is listed in the provenance block.
SKY130_RINGOSC_001
Public execution boundary
No server-side live ngspice execution, uploads, accounts, payments, comments, newsletter signup, or job/event submissions are active on this page.