Never touch DFT before although several chips already.
Just wondering when buid the scan chip in the whole chip, how i can work out how many
scan chains i need? I assume one scan chain per chip is just not practical at all?
by default,a scan chain to one clock .but you can identify the total scan-chain you need by mix multi clock and their edge. there is some configuture command and option in doing this. find them in dft compiler manual.Good Luck.