  This thesis presents the work carried out in the testing of the ATLAS
Phase-II Upgrade electronic systems in the future strips tracker after 2023, to
be installed for operations in the HL-LHC period. The high luminosity and
number of interactions per crossing that will happen after the HL-LHC starts
require a complete replacement of the ATLAS tracker. The systems that have been
defined for the Phase-II Upgrade will be designed to cope with that increased
radiation and have the right granularity to maintain the performance with
higher pile-up.
  In this thesis I present results on single modules and larger structures
comprising multiple modules.
  In the context of the current ATLAS Semiconductor Tracker studies, I present
an analysis of the data taken by the detector from the beginning of operation
in 2010 until the first Long Shut-down in 2013. The analysis consists of an
energy loss study in the Semiconductor Tracker, a task the detector was not
designed to perform.
  However, the availability of the Time-over-Threshold of the signals generated
by particles traversing the detector elements allows an estimation of the
charge deposited by the particles. This calculation of the energy loss is
typically used to perform particle identification, a feature that is usually
not required from the tracker. In addition, I present a study that proposes the
use of this energy loss calculation as a means of tracking radiation damage in
the silicon.
