preethi19
Full Member level 5
Hi can anyone please explain me what the common centroid in layout design is? In general can anyone tell me what matching is. Is matching something got to do with say a current mirror and the ratio of the say 3 transistors in the current mirror should be same (the L and W). But i did layout design and i was told to make some changes as it wasnt well matched and i was taught about say 2 cells A and B and their 4 arrangement of theirs as
AB BA, AB AB.... what does this mean??? If i have two transistor i just connect them directly. why do i have to make them AB like that. What is the need. And how am i supposed to find which transistors like that need that arrangment. As i thought all transistors play a part in the design and evrything should be proper. And i was told matching is done between ratio of the transistor. What does ratio between transistors mean? i am thinking say if in current mirror if one has (L=1u and W=1u) then the ratio of 2 of another trans will be (L=2u and W=2u)... So when i have given them right dimensions how does matching play a role????
AB BA, AB AB.... what does this mean??? If i have two transistor i just connect them directly. why do i have to make them AB like that. What is the need. And how am i supposed to find which transistors like that need that arrangment. As i thought all transistors play a part in the design and evrything should be proper. And i was told matching is done between ratio of the transistor. What does ratio between transistors mean? i am thinking say if in current mirror if one has (L=1u and W=1u) then the ratio of 2 of another trans will be (L=2u and W=2u)... So when i have given them right dimensions how does matching play a role????