Background
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SKY130 is a mature 180nm-130nm hybrid technology developed by Cypress Semiconductor that has been used for many production parts. SKY130 is now available as a foundry technology through SkyWater Technology Foundry.

The technology is the 8th generation SONOS technology node (130nm).

The technology stack consists of;

 - 5 levels of metal (`p` - penta)
 - Inductor or Inductor-Capable (`i`)
 - Poly resistor (`r`)
 - SONOS shrunken cell (`s`)
 - Supports 10V regulated supply (`10R`)


PDK Version Numbering
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The PDK version is referred to with a 3-digit number, VX.Y.Z.

* X = Milestone Release.

  - 0 indicates “alpha” level. The PDK has not undergone full qualification. Components may be immature and untested.
  - 1 indicates “beta” level. The PDK has undergone qualification testing but has not been hardware verified.
  - 2 indicates “production” level. The PDK has passed qualification testing and has been hardware verified.

* Y = Major Scheduled Release
* Z = Interim Unscheduled Release (e.g. a patch or hotfix)

Technology Naming Convention and Metal Stacks
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`s8phirs_10r`

The next letter refers to the metal stack:

* P = penta = 5 levels of metal

The following letters may occur in technology descriptions:

* H = High-density Standard Cells
* I = Inductor or Inductor-Capable
* R = poly resistor
* S = SONOS shrunken cell
* 10R = supports 10V regulated supply