Thanks again for your help. Sorry, i did not mean pin numbers, but drain number.
My problem now is when i send datas in order to open drain x, it opens drain x+1 instead. When a try to open last drain (n°7) of a TPIC chip, if opens drain 0 from next TPIC chip.
Depending on if i use one, two or zero 74HCT04 chip, the issue starts from a different TPIC chip. I will try to draw a schematic but it is quite large et and made a lot of changes for testing purpose.
About the bypass caps, do you think it may be the source of the issue? Everything is soldered on custom made PCB (i know, maybe i went too fast!) so it's not easy to add that much caps on them. Do you think one cap per group of 4 chips could be ok?
I have tried to swap chips, but so far it did not make any difference.