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Title
k

Karla Julieth Camacho Mercado

04/03/2023, 9:51 PM
Hello everyone, I'm working with sky130_fd_pr__res_xhigh_po_0p69 and I see it has 3 terminals in schematic, the bulk is connected to ground. But, in magic it doesn't have the bulk. How could I draw it? Thanks in advance.
m

Mitch Bailey

04/04/2023, 2:41 AM
@Karla Julieth Camacho Mercado The third terminal is the psubstrate connection, I believe. Normally you don’t run LVS on one isolated resistor. The substrate connection will be in a higher hierarchy. However, if you really wanted to, you could add a pwell pin labeled VGND (or whatever your schematic ground net is). Checkout the standard cells that don’t have a psub tap.
e

Enno

04/04/2023, 3:22 AM
Its only needed to calulate the capacitance against the substrate I think... So no need to have it in the layout...
a

Antony Brayan Sanabria Calderón

04/05/2023, 11:14 PM
Hi David, this is what you meant with the bulk, is this ok?, thanks for your help.
m

Mitch Bailey

04/06/2023, 12:45 AM
For the bulk contact in sky130 on magic, use
psubstratepdiff
connected by
psubstratepcontact
to
locali
.
s

SUMANTO KAR

05/13/2023, 5:24 AM
@Karla Julieth Camacho Mercado Please try using the standard one once instead of manually creating them?