What's the difference between sky130A and sky130B?
02/24/2022, 4:22 PM
reram I believe.
02/24/2022, 4:53 PM
02/24/2022, 5:09 PM
@User: The difference in the position of the metal stack (with metal2 and everything above raised to make room for the ReRAM layers) made it necessary to split out the ReRAM support as a separate PDK. The differences are minimal and really only affect parasitic capacitances and resistances in the upper metal layers. But in principle, a design spec'd to sky130A could fail if manufactured in sky130B, or vice versa, although such a scenario is unlikely. All Open MPW runs from MPW-four and up will have ReRAM support and therefore will be sky130B (MPW-four itself is a special case because we are splitting the lot so that half of it is effectively sky130A and the other half sky130B).
02/24/2022, 5:12 PM
Thank you @User
Why are there differences in parasitic R? Is it just in the via stack due to the increased M2 height?
03/01/2022, 3:40 PM
@User : The height of via1 doubles because the ReRAM layer is in the middle of it; then the via1 resistance per contact doubles. No other parasitic resistances change.
03/23/2022, 4:58 PM
@User Is there further information about this ReRAM device available anywhere? I search in the documentation but did not find anything.