Monolithic Active Pixel Sensors (MAPS) have been chosen to equip the new high-resolution and low-material Inner Tracking System (ITS) of the ALICE experiment. For this purpose TowerJazz 180 nm CMOS Imaging Sensor process, based on a high resistivity epi-layer, has been selected for a dedicated R&D activity. This presentation will address the radiation tolerance studies, the design and characterization of Explorer0, a first MAPS prototype, and the design of a data driven readout architecture based on a low power front end.
