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Optical links will be used for sending data back and forth from the counting room to the detector in the data acquisition systems for future high energy physics experiments, including ATLAS and CMS in the LHC at CERN (Switzerland) and BTeV at Fermilab (USA). This is because they can be ultra-high speed and are relatively immune to electro-magnetic interference (EMI). The baseline design for the BTeV Pixel Vertex Detector includes two types of optical link, one to control and monitor and the other to read out the hit data from the multi-chip modules on each half-plane of the detector. The design and performance of the first prototype of the Optical Readout and Control Interface for the BTeV Pixel Vertex Detector is described.

This paper describes the baseline design and a variation of the pixel module to handle the data rate required for the BTeV experiment at Fermilab. The present prototype has shown good electrical performance characteristics. Indium bump bonding is proven to be capable of successful fabrication at 50 micron pitch on real detectors. For solder bumps at 50 micron pitch, much better results have been obtained with the fluxless PADS processed detectors. The results are adequate for our needs and our tests have validated it as a viable technology.

The Beam Position Monitor (TeV BPM) readout system at Fermilab’s Tevatron has been updated and is currently being commissioned. The new BPMs use new analog and digital hardware to achieve better beam position measurement resolution. The new system reads signals from both ends of the existing directional stripline pickups to provide simultaneous proton and antiproton measurements. The signals provided by the two ends of the BPM pickups are processed by analog band-pass filters and sampled by 14-bit ADCs at 74.3MHz. A crucial part of this work has been the design of digital filters that process the signal. This paper describes the digital processing and estimation techniques used to optimize the beam position measurement. The BPM electronics must operate in narrow-band and wide-band modes to enable measurements of closed-orbit and turn-by-turn positions. The filtering and timing conditions of the signals are tuned accordingly for the operational modes. The analysis and the optimized result for each mode are presented.

The Tevatron Beam Position Monitor (BPM) readout electronics and software have been upgraded to improve measurement precision, functionality and reliability. The original system, designed and built in the early 1980’ s, became inadequate for current and future operations of the Tevatron. The upgraded system consists of 960 channels of new electronics to process analog signals from 240 BPMs, new front-end software, new online and controls software, and modified applications to take advantage of the improved measurements and support the new functionality. The new system reads signals from both ends of the existing directional stripline pickups to provide simultaneous proton and antiproton position measurements. Measurements using the new system are presented that demonstrate its improved resolution and overall performance.

This paper introduces a system to train a specific neural network device. The system allows the use of standard learning algorithms (e.g. backpropagation, Madaline III, etc.) and generates the weights for a 128 analog neural network device called ETANN (Electrically Trainable Analog Neural Network). An ultra fast weight setting algorithm stores the internal coefficients into a real analog (not computer simulated) neural network. The trainer and programmer (NETMAP) system is able to cycle through steps of learning, weight setting and parallel processing runs, performing the so called "chip-in-the-loop" procedure. The NETMAP system integrates hardware and software to interface and take full advantage of ETANN parallel processing capabilities. Due to weight setting is a complex and computationally intensive process, a solution, based on an off-line mapping between weights and pulses of charge, is proposed to speed up the loading time. >

At Fermilab, both pixel detector multichip module and sensor hybridization are being developed for the BTeV experiment. The BTeV pixel detector is based on a design relying on a hybrid approach. With this approach, the readout chip and the sensor array are developed separately and the detector is constructed by flip-chip mating the two together. This method offers maximum flexibility in the development process, choice of fabrication technologies, and the choice of sensor material. This paper presents strategies to handle the required data rate and performance results of the first prototype and detector hybridization.

The results of the BTeV silicon pixel detector beam test carried out at Fermilab in 1999-2000 are reported. The pixel detector spatial resolution has been studied as a function of track inclination, sensor bias, and readout threshold., 8 pages of text, 8 figures, Proceedings paper of Pixel 2000: International Workshop on Semiconductor Pixel Detectors for Particles and X-Rays, Genova, June 5-8, 2000

The silicon pixel vertex detector is one of the key elements of the BTeV spectrometer. Detector prototypes were tested in a beam at Fermilab. We report here on the measured spatial resolution as a function of the incident angles for different sensor-readout electronics combinations. We compare the results with predictions from our Monte Carlo simulation., Comment: 7 pages, 5 figures, Invited talk given by J.C. Wang at "Vertex 2000, 9th International Workshop on Vertex Detectors", Michigan, Sept 10-15, 2000. To be published in NIM A

A prototype 64-channel Fastbus TDC built at Fermilab is described. The module features a full custom CMOS four-channel gated integrator chip. One level of analog buffering at the inputs is implemented on chip. A four-event-deep output queue at the bus interface allows a high event rate with low dead time. Each channel can record up to two hits per event. With an occupation rate of 10%, the module can operate at 40000 events/s with dead time of the order of 15%. The TDC operates in common stop mode with a full scale of 1 mu s and a resolution of 1 ns. Data compaction and a leading word count format have been implemented. The board is less complex than current designs. >