The upgrade of the ALICE Inner Tracking System uses a newly
developed monolithic active pixel sensor (ALPIDE) which will
populate seven tracking layers surrounding the interaction point. Chips
communicate with the readout electronics using a 1.2 Gb/s data link
and a 40 Mb/s bidirectional control link. Event data are transmitted
to the readout electronics over microstrips on a Flexible Printed
Circuit and a 6 m long twinaxial cable.
This paper outlines the characterisation effort for assessing the
Data Transmission Unit performance of single sensors and
prototypes of the detector modules. It describes the different
prototypes used, the test system and procedures, and results of
laboratory and irradiation tests.