CMS Microstrip Tracker Readout at the SLHC

The increased luminosity at the SLHC and associated increases in occupancy and radiation levels present severe challenges for the CMS tracker, which will require complete replacement. Inner pixellated regions will expand to higher radii and the outer tracker region will most likely be instrumented with short strip silicon sensors. It is also necessary for the tracker to provide information to the level 1 trigger if the overall CMS trigger rate is to remain at 100 kHz. Power consumption is one of the main challenges for the tracker readout system, because of the higher granularity necessary. The current status of architectures for a short strip outer tracker readout chip is presented, with projections for performance and power consumption.