current mirror matching

[allennlowaton]

Good day EDA fellows,

I want to ask help for the layout implementation of interdigitation on
the current mirror appeared at the figure below.

Thank you.

 

[arun2011]

If M1=15, M2=300 & D is dummy interdigitation can be done as
D(20*M2)M1(20*M2)M1(20*M2)M1(20*M2)M1(20*M2)M1(20*M2)M1(20*M2)M1(20*M2)M1M1(M2*20)M1(M2*20)M1(M2*20)M1(M2*20)M1(M2*20)M1(M2*20)M1(M2*20)M1
But this will increase horz area...try using commn centroid, so that it will be a compact one..

 

[allennlowaton]

thanks arun2011...I believe I need to put the second D at other end, right?

---------- Post added at 19:04 ---------- Previous post was at 17:39 ----------

for the common centroid, I will utilized this structure:

B A B A B A B
A B A B A B A
A B A B A B A
B A B A B A B

Please share your insights regarding this one.

 

[JoannesPaulus]

You can't really use that structure since you have a ratio of 20 to 1. What you could do is a 21x15 matrix where 20 fingers of A and 1 finger of B are repeated for 15 rows.
something like this:
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
I separated the fingers in groups of 7 in the same active.
Add dummies to your liking.

 

[arun2011]

You can't really use that structure since you have a ratio of 20 to 1. What you could do is a 21x15 matrix where 20 fingers of A and 1 finger of B are repeated for 15 rows.
something like this:
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA
AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
I separated the fingers in groups of 7 in the same active.
Add dummies to your liking.

Hi Joannes
Yes, 20 to 1 ratio is a problem...but in your pattern a lot of area will be wasted and also where is the centroid and symmetry in this pattern...please explain
..

 

[JoannesPaulus]

Here is a common-centroid pattern:
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAABAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAABAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA
AAAAAAA AAAAAAA AAABAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAABAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA AAAAAAA
Of course, a lot of area is used: the grouping of 7 fingers is used to improve matching.

 

[protonixs]

AAAAAAA AAAAAAA AAAAAAA
AAABAAA AAABAAA AAABAAA
AAAAAAA AAAAAAA AAAAAAA

AAAAAAA AAAAAAA AAAAAAA
AAABAAA AAABAAA AAABAAA
AAAAAAA AAAAAAA AAAAAAA

AAAAAAA AAAAAAA AAAAAAA
AAABAAA AAABAAA AAABAAA
AAAAAAA AAAAAAA AAAAAAA

AAAAAAA AAAAAAA AAAAAAA
AAABAAA AAABAAA AAABAAA
AAAAAAA AAAAAAA AAAAAAA

AAAAAAA AAAAAAA AAAAAAA
AAABAAA AAABAAA AAABAAA
AAAAAAA AAAAAAA AAAAAAA

Use this structure, ignore the spaces. I put the spaces to emphasize the grouping.
Cheers...