IBIS is one of the two main instruments onboard the INTEGRAL gamma-ray satellite. IBIS will produce images of the gamma- ray sky in the region between 15 keV and 10 MeV by means of a coded mask coupled to a double-layer position sensitive detector. PICsIT is the detection layer optimized for high energy. It has a total area of 3065 cm2 and is composed by 4096 individual pixels made of CsI(Tl) crystal, each one with its proper electronic chain. The single units are 0.75 cm2 in area, and 3 cm thick. The front end electronics are designed so that analogue circuits, with their low noise figure, will allow the exploitation of the spectroscopic characteristics of the detector. The digital circuits will allow PICsIT to operate in anticoincidence with an active shield, and to deliver the interaction time of occurrence of the events.