open-source-silicon.dev

Hello, everyone, I have a quick question. How can I signify to magic that a metal structure is an inductor and not just a metal wire. I see the existence of rmetal layers however I have found from previous slack posts that it is probably used as a resistor metal layer and I don't know if it can be used for inductors. Technically I believe it should behave the same, showing up as a component between two nodes. Does anyone know how to do this?

I talked a little about this with <@U016EM8L91B>. I don't believe that magic extracts these devices. From the tech file
```#-------------------------------------------------------------
# The following devices are not extracted but are represented
# only by script-generated subcells in the PDK.
#-------------------------------------------------------------
# sky130_fd_pr__esd_nfet_01v8           ESD nFET
# sky130_fd_pr__esd_nfet_05v0_nvt       ESD native nFET
# sky130_fd_pr__special_nfet_pass_flash flash nFET device
# sky130_fd_pr__esd_rf_diode_pw2nd_11v0 ESD n+ diode
# sky130_fd_pr__esd_rf_diode_pd2nw_11v0 ESD p+ diode
# sky130_fd_pr__cap_vpp_*               Vpp cap
# sky130_fd_pr__ind_*                   inductor
# sky130_fd_pr__fuse_m4                 metal fuse device
#--------------------------------------------------------------```
It may be possible to extract an inductor cell as a black box device which is matched against a similar schematic item but this would probably require some modification to the extract script.

<@U03DME2F2RG> (<@U017X0NM2E7>):  The best solution that doesn't involve creating a new layer type for an inductor is to:
1. Make sure that the inductor is in its own subcell that has the same name as the device subcircuit model
2. Make sure that the inductor does not form a single net by breaking it up with a metal resistor
3. Add pins for the terminals
4. Create the property `device` with a value "`primitive` " plus any parameters that need to be passed to the device model (e.g., "`W=1` ", etc.)
5. Create the device subcircuit model, which may be just a wrapper around an ideal inductor, or contain extra components to model the inductor's resistance and capacitance to substrate, for example. 