SKIROC (Silicon Kalorimeter Integrated ReadOut Chip) is the very front end chip designed for the readout of the Silicon PIN diodes foreseen for the Electromagnetic CALorimeter (ECAL) at the future International Linear Collider. The very fine granularity of the ILC calorimeters implies a huge number of electronics channels (82 millions) which is a new feature of imaging calorimetry. Moreover, for compactness, the chips must be embedded inside the detector without any external component making crucial the reduction of the power consumption to 25 μWatt per channel. This is achieved using power pulsing, made possible by the ILC bunch pattern (1 ms of acquisition data for 199 ms of dead time).