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Monolithic circuits for the WA98 lead glass calorimeter

Description: Two monolithic circuits developed for readout of a 10,000 element lead glass calorimeter are described. The first contains 8 channels with each channel comprising a charge integrating amplifier, two output amplifiers with gains of one and eight, a timing filter amplifier and a constant fraction discriminator. This IC also contains a maskable, triggerable calibration pulser and circuits needed to form 2 by 2 and 4 by 4 energy sums used to provide trigger signals. The second IC is a companion to the first and contains 16 analog memory channels with 16 cells each, eight time-to-amplitude converters and a 24-channel analog-to-digital converter. The use of the analog memories following the integration function eliminates the need for delay cables preceding it. Characterizations of prototypes are reported, and features included to ease integration if the ICs into a readout system are described.
Date: December 31, 1994
Creator: Wintenberg, A.L.; Awes, T.C. & Britton, C.L. Jr.
Partner: UNT Libraries Government Documents Department

Design and performance of beam test electronics for the PHENIX Multiplicity Vertex Detector

Description: The system architecture and test results of the custom circuits and beam test system for the Multiplicity-Vertex Detector (MVD) for the PHENIX detector collaboration at the Relativistic Heavy Ion Collider (RHIC) are presented in this paper. The final detector per-channel signal processing chain will consist of a preamplifier-gain stage, a current-mode summed multiplicity discriminator, a 64-deep analog memory (simultaneous read-write), a post-memory analog correlator, and a 10-bit 5 {mu}s ADC. The Heap Manager provides all timing control, data buffering, and data formatting for a single 256-channel multi-chip module (MCM). Each chip set is partitioned into 32-channel sets. Beam test (16-cell deep memory) performance for the various blocks will be presented as well as the ionizing radiation damage performance of the 1.2 {mu} n-well CMOS process used for preamplifier fabrication.
Date: December 31, 1996
Creator: Britton, C.L. Jr.; Bryan, W.L. & Emery, M.S.
Partner: UNT Libraries Government Documents Department

MEMS sensors and wireless telemetry for distributed systems

Description: Selectively coated cantilevers are being developed at ORNL for chemical and biological sensing. The sensitivity can exceed that of other electro-mechanical devices as parts-per-trillion detection can be demonstrated for certain species. The authors are now proceeding to develop systems that employ electrically readable microcantilevers in a standard MEMS process and standard CMOS processes. One of their primary areas of interest is chemical sensing for environmental applications. Towards this end, they are presently developing electronic readout of a mercury-sensitive coated cantilever. In order to field arrays of distributed sensors, a wireless network for data reporting is needed. For this, the authors are developing on-chip spread-spectrum encoding and modulation circuitry to improve the robustness and security of sensor data in typical interference- and multipath-impaired environments. They have also provided for a selection of distinct spreading codes to serve groups of sensors in a common environment by the application of code-division multiple-access techniques. Most of the RF circuitry they have designed and fabricated in 0.5 {micro}m CMOS has been tested and verified operational to above 1 GHz. The initial intended operation is for use in the 915 MHz Industrial, Scientific, and Medical (ISM) band. This paper presents measured data on the microcantilever-based mercury detector. They also present design data and measurements of the RF telemetry chip.
Date: February 1, 1998
Creator: Britton, C.L. Jr.; Warmack, R.J. & Smith, S.F.
Partner: UNT Libraries Government Documents Department

Method and apparatus for providing pulse pile-up correction in charge quantizing radiation detection systems

Description: This invention is comprised of a radiation detection method and system for continuously correcting the quantization of detected charge during pulse pile-up conditions. Charge pulses from a radiation detector responsive to the energy of detected radiation events are converted to voltage pulses of predetermined shape whose peak amplitudes are proportional to the quantity of charge of each corresponding detected event by means of a charge-sensitive preamplifier. These peak amplitudes are sampled and stored sequentially in accordance with their respective times of occurrence. Based on the stored peak amplitudes and times of occurrence, a correction factor is generated which represents the fraction of a previous pulses influence on a preceding pulse peak amplitude. This correction factor is subtracted from the following pulse amplitude in a summing amplifier whose output then represents the corrected charge quantity measurement.
Date: December 31, 1992
Creator: Britton, C.L. Jr. & Wintenberg, A.L.
Partner: UNT Libraries Government Documents Department

Multiplicity-Vertex Detector Electronics Development for Heavy-Ion Detectors

Description: This paper presents the electronics work performed to date for the Multiplicity-Vertex Detector (MVD) for the PHENIX collaboration at RHIC. The detector consists of approximately 34,000 channels of both silicon strips and silicon pads. The per-channel signal processing chain consists of a pre-amplifier gain stage, a current mode summed multiplicity discriminator, a 64 deep analog memory (simultaneous read/write), an analog correlator, and a 10-bit microsecs ADC. The system controller or Heap Manager, supplies all timing control, data buffering, and data formatting for a single 256-channel multi-chip module (MCM). Each chip set is partitioned into 32-channel sets. Prototype performance for the various blocks will be presented as well as the ionizing radiation damage performance of the 1.2 mu nwell CMOS process used for fabrication.
Date: December 31, 1995
Creator: Britton, C.L., Jr.; Bryan, W.L. & Emery, M.S.
Partner: UNT Libraries Government Documents Department

Timing and control requirements for a 32-channel AMU-ADC ASIC for the PHENIX detector

Description: A custom CMOS Application Specific Integrated Circuit (ASIC) has been developed consisting of an analog memory unit (AMU) has been developed consisting of an analog memory unit (AMU) and analog to digital converter (ADC), both of which have been designed for applications in the PHENIX experiment. This IC consists of 32 pipes of analog memory with 64 cells per pipe. Each pipe also has its own ADC channel. Timing and control signal requirements for optimum performance are discussed in this paper.
Date: February 1, 1998
Creator: Emery, M.S.; Ericson, M.N. & Britton, C.L. Jr.
Partner: UNT Libraries Government Documents Department

Mixed signal custom integrated circuit development for physics instrumentation

Description: The Monolithic Systems Development Group at the Oak Ridge National Laboratory has been greatly involved in custom mixed-mode integrated circuit development for the PHENIX detector at the Relativistic Heavy Ion collider (RHIC) at Brookhaven National Laboratory and position-sensitive germanium spectrometer front-ends for the Naval Research Laboratory (NRL). This paper will outline the work done for both PHENIX and the Naval Research Laboratory in the area of full-custom, mixed-signal CMOS integrated electronics. This paper presents the architectures chosen for the various PHENIX detectors which include position-sensitive silicon, capacitive pixel, and phototube detectors, and performance results for the subsystems as well as a system description of the NRL germanium strip system and its performance. The performance of the custom preamplifiers, discriminators, analog memories, analog-digital converters, and control circuitry for all systems will be presented.
Date: October 1, 1998
Creator: Britton, C.L. Jr.; Bryan, W.L. & Emery, M.S.
Partner: UNT Libraries Government Documents Department

Trigger circuits for the PHENIX electromagnetic calorimeter

Description: Monolithic and discrete circuits have been developed to provide trigger signals for the PHENIX electromagnetic calorimeter detector. These trigger circuits are deadtimeless and create overlapping 4 by 4 energy sums, a cosmic muon trigger, and a 144 channel energy sum. The front end electronics of the PHENIX system sample the energy and timing channels at each bunch crossing (BC) but it is not known immediately if this data is of interest. The information from the trigger circuits is used to determine if the data collected is of interest and should be digitized and stored or discarded. This paper presents details of the design, issues affecting circuit performance, characterization of prototypes fabricated in 1.2 {micro}m Orbit CMOS, and integration of the circuits into the EMCal electronics system.
Date: November 1, 1997
Creator: Frank, S.S.; Britton, C.L. Jr.; Winterberg, A.L. & Young, G.R.
Partner: UNT Libraries Government Documents Department

TGV32: A 32-channel preamplifier chip for the multiplicity vertex detector at PHENIX

Description: The TGV32, a 32-channel preamplifier-multiplicity discriminator chip for the Multiplicity Vertex Detector (MVD) at PHENIX, is a unique silicon preamplifier in that it provides both an analog output for storage in an analog memory and a weighted summed-current output for conversion to a channel multiplicity count. The architecture and test results of the chip are presented. Details about the design of the preamplifier, discriminator, and programmable digital-analog converters (DACs) performance as well as the process variations are presented. The chip is fabricated in a 1.2-{micro}m, n-well, CMOS process.
Date: December 31, 1997
Creator: Britton, C.L. Jr.; Ericson, M.N. & Frank, S.S.
Partner: UNT Libraries Government Documents Department

Integrating amplifiers for PHENIX lead-glass and lead-scintillator calorimeters

Description: Two types of integrating amplifier systems have been developed for use with lead-glass and lead-scintillator calorimeters with photomultiplier tube readout. Requirements for the amplifier system include termination of the line from the photomultiplier, compact size and low power dissipation to allow multiple channels per chip, dual range outputs producing 10-bit accuracy over a 14-bit dynamic range, rms noise levels of one LSB or less, and compatibility with timing filter amplifiers, tower sum circuits for triggering and calibration circuits to be built on the same integrated circuit (IC). Advantages and disadvantages of an active integrator system are compared and contrasted to those of a passive integrator-based system. In addition, details of the designs and results from prototype devices including an 8-channel active integrator IC fabricated in 1.2 {micro}m Orbit CMOS are presented.
Date: December 31, 1995
Creator: Wintenberg, A.L.; Simpson, M.L.; Britton, C.L. Jr.; Palmer, R.L. & Jackson, R.G.
Partner: UNT Libraries Government Documents Department

Whole-arm obstacle avoidance system conceptual design

Description: Whole-arm obstacle avoidance is needed for a variety of robotic applications in the Environmental Restoration and Waste Management (ER WM) Program. Typical industrial applications of robotics involve well-defined workspaces, allowing a predetermined knowledge of collision-free paths for manipulator motion. In the unstructured or poorly defined hazardous environments of the ER WM Program, the potential for significant problems resulting from collisions between manipulators and the environment in which they are utilized is great. The conceptual design for a sensing system that will provide protection against such collisions is described herein. The whole-arm obstacle avoidance system consists of a set of sensor bracelets,'' which cover the surface area of the manipulator links to the maximum extent practical, and a host processor. The host processor accepts commands from the robot control system, controls the operation of the sensors, manipulates data received from the bracelets, and makes the data available to the manipulator control system. The bracelets consist of a subset of the sensors, associated sensor interface electronics, and a bracelet interface. Redundant communications links between the host processor and the bracelets are provided, allowing single-point failure protection. The system allows reporting of 8-bit data from up to 1000 sensors at a minimum of 50 Hz. While the initial prototype implementation of the system utilizes capacitance proximity sensor, the system concept allows multiple types of sensors. These sensors are uniquely addressable, allowing remote calibration, thresholding at the bracelet, and correlation of a sensor measurement with the associated sensor and its location on the manipulator. Variable resolution allows high-speed, single-bit sensing as well as lower-speed higher-resolution sensing, which is necessary for sensor calibration and potentially useful in control.
Date: April 1, 1993
Creator: Wintenberg, A.L.; Butler, P.L.; Babcock, S.M.; Ericson, M.N. & Britton, C.L. Jr.
Partner: UNT Libraries Government Documents Department

Johnson Noise Thermometry for Advanced Small Modular Reactors

Description: Temperature is a key process variable at any nuclear power plant (NPP). The harsh reactor environment causes all sensor properties to drift over time. At the higher temperatures of advanced NPPs the drift occurs more rapidly. The allowable reactor operating temperature must be reduced by the amount of the potential measurement error to assure adequate margin to material damage. Johnson noise is a fundamental expression of temperature and as such is immune to drift in a sensor’s physical condition. In and near the core, only Johnson noise thermometry (JNT) and radiation pyrometry offer the possibility for long-term, high-accuracy temperature measurement due to their fundamental natures. Small Modular Reactors (SMRs) place a higher value on long-term stability in their temperature measurements in that they produce less power per reactor core and thus cannot afford as much instrument recalibration labor as their larger brethren. The purpose of the current ORNL-led project, conducted under the Instrumentation, Controls, and Human-Machine Interface (ICHMI) research pathway of the U.S. Department of Energy (DOE) Advanced SMR Research and Development (R&D) program, is to develop and demonstrate a drift free Johnson noise-based thermometer suitable for deployment near core in advanced SMR plants.
Date: September 15, 2012
Creator: Britton, C.L.,Jr.; Roberts, M.; Bull, N.D.; Holcomb, D.E. & Wood, R.T.
Partner: UNT Libraries Government Documents Department

Development of a front end controller/heap manager for PHENIX

Description: A controller/heap manager has been designed for applicability to all detector subsystem types of PHENIX. the heap manager performs all functions associated with front end electronics control including ADC and analog memory control, data collection, command interpretation and execution, and data packet forming and communication. Interfaces to the unit consist of a timing and control bus, a serial bus, a parallel data bus, and a trigger interface. The topology developed is modular so that many functional blocks are identical for a number of subsystem types. Programmability is maximized through the use of flexible modular functions and implementation using field programmable gate arrays (FPGAs). Details of unit design and functionality will be discussed with particular detail given to subsystems having analog memory-based front end electronics. In addition, mode control, serial functions, and FPGA implementation details will be presented.
Date: December 31, 1996
Creator: Ericson, M.N.; Allen, M.D.; Musrock, M.S.; Walker, J.W.; Britton, C.L. Jr.; Wintenberg, A.L. et al.
Partner: UNT Libraries Government Documents Department

Post-radiation memory correction using differential subtraction for Phenix

Description: In colliders such as RHIC, the radiation levels are well below those of colliders such as LHC. The problem is that there can be enough radiation at the inner detector (Multiplicity-Vertex Detector or MVD) to significantly affect a low-priced, nonradiation-hard CMOS process. If the radiation affects the entire analog memory in a uniform fashion, then a real-time correction should be able to be performed to correct any changes seen in the memory and also the induced correlated noise from detector pickup thus precluding the need for a more expensive rad-hard process. This paper will present testing on memories fabricated in a `soft` process and exposed to ionizing radiation. We used a single pipeline as a reference to be subtracted in a cell-by-cell basis from each pipe during read out and investigated the spatial effects of using different pipes for the reference. Use of this method reduced the noise which was common to all pipes (common-mode noise) and thus reduced both common-mode input noise and pattern noise generated from address lines being exercised on the AMU. The correlation across the memories (6-, 8-, and 16-channel AMUs fabricated in the Orbit 1.2{mu} CMOS process) vs. radiation dose was found to be quite good. Both pre-and post-radiation results are presented on systems designed for PHENIX and WA98 at CERN as well as measured results on the minimization of the effects of injected systematic noise.
Date: June 1, 1995
Creator: Britton, C.L. Jr.; Wintenberg, A.L.; Womac, M.; Kennedy, E.J.; Smith, R.S.; Young, G.R. et al.
Partner: UNT Libraries Government Documents Department

WA80 BGO calorimetry electronics

Description: This paper describes instrumentation designed for BGO scintillator-based calorimetry of particles covering a very wide range of energies (from less than 50 MeV to 50 GeV). The instrumentation was designed to have a measurement accuracy of 0.1% over as much of the energy range as possible so the energy resolution of BGO would be the limiting factor. Two 1.5-cm{sup 2} photodiodes were used per 2.5 cm {times} 2.5 cm {times} 25 cm BGO crystal. Both a charge-sensitive preamplifier and a pulse processor were developed specifically for the needs of the WA80 experiment. The preamplifier was designed for high detector capacitance (100 to 700 pF), low integral and differential non-linearity and low power consumption (200 mW). The pulse processor is a time-invariant shaping amplifier with integral peak-detect-and-hold and automatic gain selection circuits. The amplifier use quasi-triangular shaping with 4 {mu}s peaking time, and the hold circuit is gated with a fast first level trigger. The system has more than 20 bits of effective resolution when used with an external 12-bit ADC. Results from beam tests at CERN are presented. 6 refs., 5 figs., 1 tab.
Date: October 31, 1991
Creator: Wintenberg, A.L.; Britton, C.L. Jr.; Ericson, M.N.; Maples, R.A.; Young, G.R. & Awes, T.C.
Partner: UNT Libraries Government Documents Department

A multi-channel ADC for use in the PHENIX detector

Description: A custom CMOS analog to digital converter was designed and a prototype 8-channel ADC ASIC was fabricated in a 1.2 {mu}m process. The circuit uses a Wilkinson-type architecture which is suitable for use in multi-channel applications such as the PHENIX detector. The ADC design features include a differential positive-ECL input for the high speed clock and selectable control for 11 or 12-bit conversions making it suitable for use in multiple PHENIX subsystems. Circuit topologies and ASIC layout specifics. including power consumption, maximum clock speed, INL. and DNL are discussed. The ADC performed to 11-bit accuracy.
Date: December 31, 1996
Creator: Emery, M.S.; Frank, S.S.; Britton, C.L. Jr.; Wintenberg, A.L.; Simpson, M.L.; Ericson, M.N. et al.
Partner: UNT Libraries Government Documents Department

A Radiation-Hard Analog Memory In The AVLSI-RA Process

Description: A radiation hardened analog memory for an Interpolating Pad Camber has been designed at Oak Ridge National Laboratory and fabricated by Harris Semiconductor in the AVLSI-RA CMOS process. The goal was to develop a rad-hard analog pipeline that would deliver approximately 9-bit performance, a readout settling time of 500ns following read enable, an input and output dynamic range of +/-2.25V, a corrected rms pedestal of approximately 5mV or less, and a power dissipation of less than 10mW/channel. The pre- and post-radiation measurements to 5MRad are presented.
Date: December 31, 1995
Creator: Britton, C.L. Jr.; Wintenberg, A.L.; Read, K.F.; Simpson, M.L.; Young, G.R.; Clonts, L.G., Kennedy, E.J., Smith, R.S., Swann, B.K. et al.
Partner: UNT Libraries Government Documents Department

A bipolar monolithic preamplifier for high-capacitance SSC (Superconducting Super Collider) silicon calorimetry

Description: This paper describes a preamplifier designed and fabricated specifically to address the requirements of silicon calorimetry for the Superconducting Super Collider (SSC). The topology and its features are discussed in addition to the design methodology employed. The simulated and measured results for noise, power consumption, and speed are presented. Simulated an measured data for radiation damage effects as well as data for post-damage annealing are also presented. 8 refs., 7 figs., 2 tabs.
Date: January 1, 1990
Creator: Britton, C.L. Jr. (Oak Ridge National Lab., TN (USA)); Kennedy, E.J. (Tennessee Univ., Knoxville, TN (USA). Dept. of Electrical and Computer Engineering Oak Ridge National Lab., TN (USA)) & Bugg, W.M. (Tennessee Univ., Knoxville, TN (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Considerations on the design of front-end electronics for silicon calorimetry for the SSC (Superconducting Super Collider)

Description: Some considerations are described for the design of a silicon-based sampling calorimetry detector for the Superconducting Super Collider (SSC). The use of silicon as the detection medium allows fast, accurate, and fine-grained energy measurements -- but for optimal performance, the front-end electronics must be matched to the detector characteristics and have the speed required by the high SSC interaction rates. The relation between the signal-to-noise ratio of the calorimeter electronics and the charge collection time, the preamplifier power dissipation, detector capacitance and leakage, charge gain, and signal shaping and sampling was studied. The electrostatic transformer connection was analyzed and found to be unusable for a tightly arranged calorimeter because of stray capacitance effects. The method of deconvolutional sampling was developed as a means for pileup correction following synchronous sampling and analog storage. 3 refs., 6 figs.
Date: January 1, 1990
Creator: Wintenberg, A.L.; Bauer, M.L.; Britton, C.L. Jr.; Kennedy, E.J.; Todd, R.A. (Oak Ridge National Lab., TN (USA)); Berridge, S.C. et al.
Partner: UNT Libraries Government Documents Department

A four-channel bipolar monolithic preamplifier for RHIC dimuon pad readout

Description: This paper presents a four-channel, low power-consumption bipolar monolithic preamplifier designed to amplify signals from pads with detector capacitance values from 10 pF to 50 pF used in a RHIC (Relativistic Heavy Ion Collider) dimuon experiment. The circuit utilizes a folded-cascode topology with a novel feedforward compensation that improves the low-capacitance transient response and provides self-biasing without resorting to bandgap or current references. The circuit was fabricated by Harris Semiconductor in the VHF dielectrically isolated complementary bipolar process. Measured data for gamma irradiation to 1.25 MRad are presented. 6 refs., 7 figs., 2 tabs.
Date: January 1, 1991
Creator: Britton, C.L. Jr.; Todd, R.A.; Wintenberg, A.L.; Young, G.R. (Oak Ridge National Lab., TN (United States)) & Kennedy, E.J. (Tennessee Univ., Knoxville, TN (United States). Dept. of Electrical and Computer Engineering)
Partner: UNT Libraries Government Documents Department

Multiple Input Microcantilever Sensor with Capacitive Readout

Description: A surface-micromachined MEMS process has been used to demonstrate multiple-input chemical sensing using selectively coated cantilever arrays. Combined hydrogen and mercury-vapor detection was achieved with a palm-sized, self-powered module with spread-spectrum telemetry reporting.
Date: March 11, 1999
Creator: Britton, C.L., Jr.; Brown, G.M.; Bryan, W.L.; Clonts, L.G.; DePriest, J.C.; Emergy, M.S. et al.
Partner: UNT Libraries Government Documents Department

Bipolar monolithic preamplifiers for SSC silicon calorimetry

Description: This paper describes preamplifiers designed specifically to address the requirements of silicon calorimetry for the Superconducting Super Collider (SSC). Eight different preamplifiers designed for detector capacitances ranging from 20 pF to 500 pF and operating temperatures from 25{degree}C to {minus}20{degree}C are discussed. The preamplifiers were fabricated with two different high-frequency processes (one with the VTC, Inc. VJ900 process, seven with the Harris Semiconductor VHF Process). The different topologies and their features are discussed in addition to the design methodologies employed. The results for noise, power consumption, speed, and radiation damage effects as well as data for post-damage annealing are presented for the VTC process preamplifier. Simulations for the VHF Process circuits are presented. This work was funded through SSC Generic Detector funding, SSC Detector Subsystem funding, and the Oak Ridge National Laboratory (ORNL) Detector Center.
Date: January 1, 1990
Creator: Britton, C.L. Jr.; Todd, R.A.; Bauer, M.L. (Oak Ridge National Lab., TN (USA)); Kennedy, E.J. (Tennessee Univ., Knoxville, TN (USA). Dept. of Electrical and Computer Engineering Oak Ridge National Lab., TN (USA)) & Bugg, W.M. (Tennessee Univ., Knoxville, TN (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Radiation effects on junction field-effect transistors (JFETS), MOSFETs, and bipolar transistors, as related to SSC circuit design

Description: Some results of radiation effects on selected junction field-effect transistors, MOS field-effect transistors, and bipolar junction transistors are presented. The evaluations include dc parameters, as well as capacitive variations and noise evaluations. The tests are made at the low current and voltage levels (in particular, at currents {le}1 mA) that are essential for the low-power regimes required by SSC circuitry. Detailed noise data are presented both before and after 5-Mrad (gamma) total-dose exposure. SPICE radiation models for three high-frequency bipolar processes are compared for a typical charge-sensitive preamplifier.
Date: January 1, 1990
Creator: Kennedy, E.J. (Tennessee Univ., Knoxville, TN (USA) Oak Ridge National Lab., TN (USA)); Alley, G.T.; Britton, C.L. Jr. (Oak Ridge National Lab., TN (USA)); Skubic, P.L. (Oklahoma Univ., Norman, OK (USA)); Gray, B. & Wu, A. (Tennessee Univ., Knoxville, TN (USA))
Partner: UNT Libraries Government Documents Department