Samsung s7 no power dead

Hi friends, I am struggling with several Samsung S7 and S7 Edge that suddenly stopped working, turning off without a real motivation.  In charge I have an absorption of 0.27A, if connected directly to the battery, the same result (only after pressing the power button) according to my opinion, these devices heat up too much and end up turning off without giving more signs of life.  I have 3 Samsung S7 all with the same defect, could it be the CPU or something else? Thanks for your opinion