Hello , My question is specific regarding a phenomena of the current spike amplitude.(so i open a fresh question about it).
Why on C1 capacitor i got a much bigger current spike then on C4?
What is the logic for spike current dividing between C1 and C4?
I know I=C*dV/dT so C1 is much begger thus bgger current.
but do they share this totall amount of charge?
so the bigger C1 the smaller C4 current spike on it?
Thanks.

 

If you raise the value of C1 without changing C4, the current in C1 increases but the current in C4 stays the same. The formula is valid for each capacitor individually and also for the IC output using the combined capacitance.

 

Assuming that both capacitors have zero (or sufficiently small) series resistance, then the current spikes will be in the same ratio as the capacitances. In order to change the 1 µF cap by the same voltage as a 100 pF cap, you need to add 10,000 times as much charge in the same amount of time. But it's not really a question of sharing the charge since each capacitor is completely uanware of the presence of the other one (in reality, this is not the case because parasitics cause some interaction).