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RTimothyEdwards / open_pdks

PDK installer for open-source EDA tools and toolchains. Distributed with setups for the SkyWater 130nm and Global Foundries 180nm open processes.
http://opencircuitdesign.com/open_pdks
Apache License 2.0
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sky130 chip_io: mag file does not correspond to gds #419

Closed d-m-bailey closed 12 months ago

d-m-bailey commented 12 months ago

In 3da499bf3cb58e44aa0f2360a672c7187994a08b, a metal3 resistor was added to separate VSSIO and VDDIO nets in sky130_ef_io__vccd_lvc_clamped3_pad.mag and sky130_ef_io__vssd_lvc_clamped3_pad.mag.

I can't find the corresponding change in the gds data at $PDK_ROOT/$PDK/libs.ref/sky130_fd_io/gds/sky130_ef_io.gds for volare pdk versions after that. The tapeout data for 2311 does not contain metal3 resistors in those cells.

This causes an mismatch in all LVS checks that includes chip_io and its variants.

d-m-bailey commented 12 months ago

Looks like the original fix to the cells was April 26, 2023 at 2d93509249763cb83dae021fd0dbf3c79e262f47. Commit details are here.

To get a netlist that will match the current layout, probably have to go back to before that.

d-m-bailey commented 12 months ago

My mistake. Trying to use a recent pdk on a tape out with a much older version.