High-speed operational amplifiers are widely used in quantum-optical systems and equipment for recording fast pulses. The high level of parameters of such products is ensured by the use of modern ...technological routes for manufacturing microcircuits containing complementary bipolar transistors with a high cutoff frequency and a low parasitic collector capacitance. These technological routes for the manufacture of microcircuits are not available in Russia and Belarus. In order to meet the existing needs of the domestic market for radio-electronic equipment, two operational amplifiers on an MN2KhA031 master slice array (MSA) with unified stages and the possibility of changing the parameters by selecting the resistance of the current-conducting resistors and the capacity of the balancing capacitor are presented. The circuit diagrams are described and the results of the circuit modeling of two products are presented: a high-speed operational amplifier OAmp9 with a gain bandwidth product of more than 600 MHz, an output voltage rise rate of over 400 V/μs with the static parameters corresponding to general-purpose operational amplifier applications, and a precision low-noise OAmp10 amplifier with a gain of about 2 × 10
6
, an offset voltage of less than 50 μV, and a spectral noise floor relative to the input of about 1 nV/Hz
0.5
. The directions for further modernization of the developed amplifiers are formulated, especially, the reduction of the parasitic collector capacitance of transistors by design engineering, applying a reverse bias voltage, and the application of nonlinear correction circuits, which allow bringing the amplifiers’ performance in the large-signal mode closer to their performance in the low-signal mode.
—
An MH2XA031 master slice array (basic matrix crystal (BMC)) is applied for designing and semicustom production of analog integrated circuits (ICs) operating in extreme conditions. It can be ...effectively used only with a clear understanding of the permissible ranges of changes in the parameters of analog components when exposed to various types of penetrating radiation. In this study, with the help of circuit simulation, the effect of neutron fluence up to 10
14
neutrons/cm
2
and the absorbed dose of gamma rays up to 3 Mrad on the static parameters of the components of the MH2XA031 circuit design library—an ADComp3 comparator, an OAmp2 low zero offset voltage operational amplifier, an OAmp8 multidifferential operational amplifier, and a charge-sensitive amplifier (CSA) with an input double-gate transistor—is studied. It is established that the ADComp3 comparator, the OAmp2 and OAmp8 amplifiers, and the CSA remain operational at an absorbed dose of gamma rays equal to 3 Mrad. The permissible neutron fluence values for ADComp3, OAmp8, and CSA are 10
14
neutrons/cm
2
; and for OAmp2, 10
13
neutrons/cm
2
. It is established that modeling the radiation changes in the parameters of the components at higher neutron fluences (more than 10
14
neutrons/cm
2
) and the absorbed gamma quanta of more than 3 Mrad is advisable after experimental verification of the adequacy of the transistor models used at the specified levels of penetrating radiation.
MPD TPC Status Averyanov, A.; Balashov, I.; Bazhazhin, A. ...
Physics of atomic nuclei,
10/2023, Letnik:
86, Številka:
5
Journal Article
Recenzirano
In the framework of the JINR scientific program on study of hot and dense baryonic matter a new accelerator complex Ion Collider fAcility (NICA) based on the Nuclotron-M is under realization. It will ...operate at a luminosity up to
cm
s
for ions up to Au79+. Two interaction points are foreseen at NICA for two detectors which will operate simultaneously. One of these detectors, the Multi-Purpose Detector (MPD), is optimized for investigations of heavy-ion collisions. The Time-Projection Chamber (TPC) is a well-known detector for 3-dimensional tracking and particle identification for high multiplicity events. The conceptual layout of MPD, TPC design and its parameters, the current status of the readout based on multiwire proportional chamber (MWPC) and readout electronics based on SAMPA chip as well as the status of TPC subsystems are presented.
For the production of integrated analog circuits with a small-scale integration, which are developed to operate at temperatures up to minus 200 ℃ and/or with absorbed dose of gamma radiation up to 5 ...Mrad, a gallium arsenide master slice has been created. The following types of active elements are used in this master slice: DpHEMT with gate dimensions 100 ηm/0,2 ηm and 10 ηm/0,2 ηm;
p-n-p
HBT, they were chosen for realization of most common analog circuits of operational amplifiers, comparators, voltage followers. Despite the small number of available DpHEMT with high transconductance for circuit synthesis and volt-ampere characteristics features of DpHEMT experimental samples, which exclude use of those transistors at low drain current, master slice give opportunity for developing charge-sensitive amplifiers (CSA) circuits with only one type of active elements – DpHEMT. At the same time, correct choice of the operating point of transistors provide development of low-noise, high-speed CSAs with better parameters than silicon CSAs for sensors with internal capacitance up to 100 pF. So, developed on GaAs master slice CSA with head DpHEMTs and ratio of the gate width to its length, equal to W/L = 2000 and W/L = 3000, characterized by current consumption I
CC
= 5,46 mA and I
CC
= 5,25 mA, rise time t
R
= 10,7 ns and t
R
= 9,6 ns, equivalent noise charge ENC = 3960 el, and ENC = 3700 el. with sensor capacitance of 50 pF, while the CSA with a head silicon
p
-channel junction field-effect transistor has W/L = 3870, I
CC
= 6,99 mA, t
R
= 27,7 ns, ENC = 5360 el. with the same sensor capacitance.
Abstract
The present work is devoted to the study of the evaporation process of micro-sized water droplets levitating over a heated dry substrate. The study of this process is relevant in connection ...with the development of spray cooling systems. Due to the extreme complexity of this phenomenon the mechanism of spray cooling is still not fully understood. In this work we studied the evaporation of micro-sized water droplets levitating over a dry substrate heated from below. The working area was open to the atmosphere. Evaporation was studied in the temperature substrate range from 23 to 95°C. During the experiment local values of the substrate temperature and geometric characteristics of the drop were determined. In the experiment a shadow method with high spatial resolution was used, shooting was performed with a high-speed camera.
Abstract
The needs of microelectronics for heat removal are growing and have already exceeded the value of 1 kW/cm
2
. To assess the ability of jet impingement cooling to meet the growing ...requirements, a review of experimental studies was conducted. The review demonstrated both the lack of progress in increasing critical heat flux value over the past 30 years, and the fact that this technique is still considered effective and promising. The review showed that the movement to intensify heat transfer is in the same direction as in other promising cooling technologies. It is noted that the most productive heat transfer occurs in the region of the thinnest liquid film spreading from a free impingement liquid jet. New fundamental studies are discussed that note the significance of heat transfer values in a very thin liquid film, and this is important for the development of cooling technologies. Problems are formulated for the required detailed studies of highly dynamic processes in the boiling region of an ultrafine liquid film at the micro level, aimed at intensifying heat transfer.
Low temperature multi-differential operational amplifier Dvornikov, O. V.; Tchekhovski, V. A.; Dziatlau, V. L. ...
Doklady Belorusskogo gosudarstvennogo universiteta informatiki i radioèlektroniki,
08/2021, Letnik:
19, Številka:
5
Journal Article
Recenzirano
Odprti dostop
A multi-differential operational amplifier, called OAmp3, designed for operation at temperatures up to minus 197 °С and developed on bipolar transistors and junction field-effect transistors of the ...master slice array МН2ХА030, is considered in the article. The circuitry features of the OAmp3 allow, due to the use of various negative feedback circuits, to implement a set of functions necessary for signal processing on a single amplifier: amplification (or current – voltage conversion), filtering, shift of the constant output voltage level. The performed measurements of OAmp3, connected as instrumentation amplifier circuit, showed that all manufactured products retain their performance in the temperature range from minus 150 °С to 20 °С, and individual samples – at minus 197 °С. It was found that the main reason for the loss of OAmp3 performance is an increase of the resistance of semiconductor resistors by almost 5.4 times at minus 197 °С compared to normal conditions and decrease in the junction field-effect transistor drain current. Together, these factors lead to decrease in the current consumption of the OAmp3 by almost 31 times at minus 180 °С compared to normal conditions. To reduce the temperature dependence of the current consumption and, thus, save the OAmp3 operability at low temperatures without changing the technological route of integrated circuits manufacturing, it is proposed to replace high-resistance semiconductor resistors with “pinch-resistors” formed on a small-signal p-junction field-effect transistor. The article presents the OAmp3 connection circuit in the form of an instrumental amplifier, the method and results of low-temperature measurements of experimental samples.
The results of the simulation the influence of the proton flux on the electrical characteristics of the device structure of dual-channel high electron mobility field effect transistor based on GaAs ...are presented. The dependences of the drain current ID and cut-off voltage on the fluence value and proton energy, as well as on the ambient temperature are shown.
The aim of the work is analyzing the results of an experimental research of a charge-sensitive amplifier with an adjustable conversion coefficient and a base level recovery circuit fabricated on the ...master slice array MN2XA030 for silicon photomultiplier tubes. The amplifier is called ADPreampl3. The parameters were measured on a small batch of chips in the amount of 20 samples. In the process of measuring the main parameters of the amplifier, the signal from the SiPM Photonique equivalent circuit was fed to the amplifier input. In the course of measuring the parameters, it was revealed that the spread of the baseline level for the FOut output ranged from -24 to 276 mV with an average value of 85.6 mV. In this case, a voltage changing in the FOoutShift node from -3 to 3 V is sufficient to establish a base level value of FOut output close to zero. When the recovery scheme is disabled, the spread of the basic level for OutA output is from 300 to 800 mV. When the OutAShift output is connected to the zero-voltage bus the average base level for OutA output is 3.72 mV and for OutAinv output it is minus 2.42 mV. The base level at the outputs OutA and OutAinv smoothly changes in the range of ± 0.9 V. At maximum gain, the dynamic range of ADPreampl3 exceeds 20 dB, however, at the same time, the conversion coefficient depends on the value of the input charge. To register large input charges, it is recommended to reduce the output pulse by reducing the voltage at the Gain pin or process the signal from the FOut pin. The output parameters of the experimental samples are compared with the results of computer simulation. The discrepancy between the results of modeling and measurements, peak time and propagation delays of the amplifier signal was revealed. Based on this, a decision to adjust the SPICE parameters of the elements used in the simulation was made.
The present research is devoted to the evaporation of micro-sized water droplets on a smooth silicon substrate heated from below. The study of this process is relevant for the development of spray ...cooling systems. Due to the extreme complexity of this phenomenon the mechanism of spray cooling is not fully understood yet. In our experiment the silicon substrate is open to the atmosphere. Evaporation of sessile droplets with the size of the order of 10 μm is studied at the substrate temperature ranging from 23 to 100°C. A shadow method coupled with a high-speed camera is used in the experiment to determine the geometric characteristics of the droplet profile and to calculate the droplet evaporation rate.