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Hello, all. I'm facing latch-up error in DRC as below.
but I dont' have any idea how to resolve it after reading descriptions.
Could you give me any advice?

Within 15um from the edge of the NCOMP connected to I/O pad (marked by Latchup_MK):
Max Nwell tap distance to PCOMP inside Nwell
(irrespective of its direct connection to Pad) = 2

<@U04TWKZ0JSU> Do you have layer Latchup_MK `137/5` over this circuit? Does this circuit have a direct connection from the pad to the ncomp?

<@U04TWKZ0JSU>:  You seem to be using standard cells without abutting them properly.  You don't have taps close to (within 15um) of any point in any standard cell, which is what causes the latchup error.  Standard cells should always be placed abutting each other and with taps placed at regular intervals.

<@U04TWKZ0JSU> When I use standard cells in manual layout, I put endcap cell to avoid latchup error.

Thank you <@U017X0NM2E7> <@U016EM8L91B> <@U03S86AELQ6> for advices.
I added another endcap to the left side as below (1) and it solved LU.3 and LU.4 DRC errors.
but IO.1b(2) and IO.1a2(3) are not solved.
About (3), I don't understand why thoes errors happened

Yes. they are connected with pad
<https://open-source-silicon.slack.com/archives/C04MJUYP99V/p1715596750398429?thread_ts=1715583036.658639&amp;cid=C04MJUYP99V>

<@U04TWKZ0JSU> It looks like your end tap cells may have been placed with nwell abutting. They should be placed with cell boundaries abutting. nwell will overlap.

For IO errors, diffusion connected to directly to pads need double guard rings.

<@U017X0NM2E7>
did you mean this is cell boundry abutting?

<@U04TWKZ0JSU> Yes, standard cell is designed to abut at the edge of npus/pplus and power/ground rail.
not at the cell boundary. When cells are aligned correctly, cells are overlapped and nplus/pplus and power/ground rail are connected

<@U017X0NM2E7>
About IO error :
Its DVDD and DVSS are connected to pad and it may occur error due to no double guardring as you said.
but orange-circled one is connecte to pad(DVDD and DVSS) but it doesn't has an error.
I fixed standard cell abuttings(but this modification is not tested yet.) Is the standard cell to connected to pad still needed to guardring?