@Stefan Schippers, @Tim Edwards, I am looking for photo diode symbol which can be used for simulation in xschem for some sensor circuit. Is photo diode model/symbol is available in sky130nm pdk ? I can see document on layout of photo diode here (https://skywater-pdk.readthedocs.io/en/main/rules/periphery.html#photo - it shows the DRC rules only ) but did not find any info on its symbol.

@Deepak as soon as I know if and how this device is described for SPICE simulation I can create a symbol for it. In the mean time you can place a diode, change the model and/or the device prefix ('D' or 'X' or whatever) if you have a photo diode model to work with.

@Stefan Schippers: In

models_diodes.spice

lines 838 and following:

.subckt  sky130_fd_pr__photodiode a c mult=1

@Deepak @Tim Edwards I have added photodiode.sym in the xschem_sky130/sky130_fd_pr symbols, tested basic dc sweep in simulation.

Thank you @Stefan Schippers. Sorry, I was out for few days so could not reply you. I will try this in simulation and let you know. Also is there any example test circuit you have added in examples folder for the photodiode?

I have added a test in the

sky130_tests/test_diode.sch

. Not a comprehensive test, just basic dc sweep.

@Stefan Schippers, i am getting unknown subckt error on running test_diode.sch for photo diode (shown in added ss). I have included models_diodes.spice file as well , still same error.