SKY130 gm/ID Explorer

An interactive, browser-based gm/ID characterisation tool for the SkyWater SKY130 open-source 130nm CMOS PDK.

Website

Open the tool in your browser. Click the link, or copy the URL:

Open the SKY130A gm/ID Explorer

https://nithinpuru.github.io/gmid/sky130a/

All PDKs (SKY130A, GF180MCU-D, IHP SG13G2):

Open the gm/ID Explorer (all PDKs)

https://nithinpuru.github.io/gmid/

Note: The PDK Reference panel is a summary and may contain inaccuracies. Always check values against the official SkyWater PDK documentation before relying on them.

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What is this?

This tool lets you explore the gm/ID characteristics of 7 MOSFET variants in the SKY130 PDK directly in your browser. You don't need Python, MATLAB or a local install.

Derived from simulation data in chennakeshavadasa/gmid_SKY130, converted into a fully interactive Plotly dashboard with a comprehensive PDK reference panel pulled from the official skywater-pdk documentation.

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Features

PDK Reference Panel

• Full explanation of all 7 MOSFET variants: LVT / SVT / HVT flavours and HV (5V/10.5V) devices
• Explanation of what LVT, SVT, HVT actually mean in SKY130 (same gate oxide, different Vt-adjust implants)
• Why nfet_01v8_hvt does NOT exist in SKY130 (only PMOS HVT)
• HV device explanation — why g5v0d10v5 is an extended-drain DMOS, not just a thick-oxide FET
• EP electrical specs: Vth₀, SubVt slope, Ioff, Vds limits for all devices
• 7-corner guide: TT / SS / FF / SF / FS / leak / wafer
• Instance parameter limits (Wmin, Lmin) — PMOS Lmin=0.35µm vs NMOS 0.15µm
• Designer's quick-reference cheatsheet

gm/ID Explorer

• 7 device variants: NMOS/PMOS SVT/LVT/HVT + HV family
• 7 interactive Plotly plots:
  • gm/ID vs Vgs
  • gm/ID vs Vov (= Vgs − Vth)
  • gm/gds vs gm/ID (intrinsic gain)
  • ID/W vs gm/ID (normalised current density)
  • fT vs gm/ID (transit frequency)
  • Cgd/Cgg vs gm/ID
  • Cgs/Cgg vs gm/ID
• Overview mode — 6 plots simultaneously
• Channel length filter — per-L toggle or quick All/Short/Long
• Log scale toggles for X and Y
• PNG export of any plot

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Device Summary

Dataset name	PDK model	Type	Vdd	Lmin	Vth₀ typ	Notes
NMOS_01v8_SVT	nfet_01v8	NMOS SVT	1.8V	0.15µm	~0.49V	Standard workhorse
NMOS_01v8_LVT	nfet_01v8_lvt	NMOS LVT	1.8V	0.15µm	~0.40–0.45V	Low-Vt, higher speed
PMOS_01v8_SVT	pfet_01v8	PMOS SVT	1.8V	0.35µm	~0.60–0.65V	Standard PMOS
PMOS_01v8_LVT	pfet_01v8_lvt	PMOS LVT	1.8V	0.35µm	~0.52V	Low-Vt PMOS
PMOS_01v8_HVT	pfet_01v8_hvt	PMOS HVT	1.8V	0.35µm	~0.74V	Low-leakage, power gating
NMOS_g5v0d10v5	nfet_g5v0d10v5	NMOS HV	5V/10.5V	0.5µm	~0.78–0.85V	Extended drain DMOS
PMOS_g5v0d10v5	pfet_g5v0d10v5	PMOS HV	5V/10.5V	0.5µm	~0.90–1.0V	Extended drain DMOS

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Data Source

Simulation data: chennakeshavadasa/gmid_SKY130
ngspice DC sweeps (Vgs step 0.1 mV, W = 2 µm) across 7 device variants and 11–13 channel lengths each.

PDK documentation: skywater-pdk.readthedocs.io
Apache 2.0 licensed. © SkyWater Technology / Google.

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Technical Notes

• 400 points per curve, uniformly downsampled from 17.5k–49.5k raw points. This is visually lossless for smooth gm/ID curves.
• Single index.html with the data embedded. It loads Plotly.js v2.27.0 from a CDN and needs no backend.
• Total file size: ~3.5 MB
• To run it locally, download index.html and open it in a browser (internet access is needed for Plotly).

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License

Tool code: MIT License
Simulation data: see original repo
PDK specs: Apache 2.0 © SkyWater Technology / Google

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Related

• gm/ID Explorer (all PDKs): SKY130A, GF180MCU-D and IHP SG13G2
• GF180MCU gm/ID Explorer: the same tool for the GF 180nm MCU PDK
• gmid_SKY130: raw simulation data, Xschem testbenches and Python plotting scripts

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Built for the open-source silicon community. If you find it useful, please star the repository.