Development of a readout technique for the high-data-rate BTeV pixel detector at Fermilab

The pixel detector for the BTeV experiment at Fermilab provides digitized data from approximately 22 million silicon pixel channels. Portions of the detector are 6 mm from the beam, providing a substantial hit rate and high radiation dose. The pixel detector data will be employed by the lowest level trigger system for track reconstruction every beam crossing. These requirements impose a considerable constraint on the readout scheme. This paper presents a readout technique that provides the bandwidth that is adequate for high hit rates, minimizes the number of radiation-hard components, and satisfies all other design constraints.