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One of directions of improving parameters of analog integrated circuits is a development of new and modernization of existing designs of integrated elements without significantly changing of a technological route of integrated circuit manufacturing with a simultaneous creation of new integrated elements models. The article considers the results of experimental studies of the double gate junction field-effect transistor manufactured according to the 3CBiT technological route of JSC Integral. Based on the obtained results, the electrical model of double gate junction field-effect transistor is proposed, which describes the features of its application in analog integrated circuits. Comparison of I-V characteristics of measurements results and created model simulation are presented. A small capacity and a reverse current of a double gate junction field-effect transistor top gate, an ability to compensate for the DC (direct current) component of an input current provide a significant improvement in the characteristics of analog integrated circuits such as electrometric operational amplifiers and charge-sensitive amplifiers. The developed double gate junction field-effect transistor can be used in signal readout devices required in the analog interfaces of space instrument sensors and nuclear electronics.

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.

Structured arrays and master slice arrays are often used to reduce cost, design and test time for radiation hardened analog integrated circuits. One of such master slice arrays is МН2ХА030, which uses bipolar and junction field-effect transistors. The purpose of this article is to estimate the effect of ionizing radiation on the parameters of the operational amplifier OAmp2 and comparators ADComp1 and ADComp3 created on the МН2ХА030 master slice array. Еhe results of measurements of analog components after exposure to 60Co gamma quanta with an absorbed dose of up to 700 krad and a fast electron fluence of up to 2.9·1015 el./cm2 with an energy of 6 MeV are presented. The OAmp2 operational amplifier provides a satisfactory level of basic static parameters (input current, offset voltage, voltage gain) at a fast electron fluence of up to 3.7·1014 el./cm2 with an energy of 6 MeV. There are a decrease in the voltage gain and an increase in the offset voltage at electron fluence of greater than 1015 el./cm2. The latter can be caused by a decrease in the efficiency of the common-mode signal feedback integrated into operational amplifier with a significant drop in current gain of bipolar transistors. All considered analog components provide a satisfactory level of basic static parameters at a fast electron fluence of up to 3.7·1014 el./cm2 with an energy of 6 MeV and an absorbed dose of 60Co gamma quanta of at least 700 krad. It is assumed that resistance of OAmp2, ADComp1, ADComp3 to the action of 60Co gamma quanta is significantly higher and requires further research. The developed analog components can be used in signal reading devices required in front-end of sensors for space instrumentation and nuclear electronics.

It is proved that the development of the state depends on the effective functioning of the educational system, which provides training of highly qualified personnel, forms human capital, ensures the development of scientific activity. Along with this, the domestic educational system is characterized by transitional features, where the principles and approaches of the European educational system are implemented and the rudiments of the Soviet system remain. The relevance and necessity of the study are determined. The purpose of the study is to determine the prospects for the development of the educational system of Ukraine by forming and implementing an educational program for land protection. Achieving this goal lies in solving the following tasks: analysis of the state of functioning of the educational system of Ukraine; determination of directions and tendencies of development of the educational system of Ukraine; development of proposals to increase the efficiency of the educational system of Ukraine; determine the directions and peculiarities of the formation and implementation of the educational program for the protection of land. Characterizing the state and trends in the educational system of Ukraine, a decrease in the number of preschool education institutions in 2019 compared to 1990 by 40%, the number of places in preschool education institutions - 49%, the number of people in preschool education institutions - 49%, along with growth the level of coverage of children by preschool institutions. The study found a decrease in the number of colleges, technical schools, colleges by 54% and the number of students in these institutions by 77%. Along with this, there is an increase in the number of universities, academies, institutes by almost 1.9 times and the number of people - more than 1.4 times. The problematic aspects observed in the educational system of Ukraine are determined, the directions and prospects of its development are offered. The directions and peculiarities of the formation and implementation of the educational program of land protection, taking into account the modern directions of land use transformations are determined.

The article analyzes the historical periods of development of the taxation system in Soviet times and during the independence of Ukraine. The stages of transformation of the country’s taxation system and the deduction of the development of the national taxation system are outlined. It was found that during the years of independence there were five transformations of the tax system in 1991, 1995, 1999, 2011 and 2015, respectively. The preconditions of each of the specified stages of realization of transformation of system of the taxation are analyzed. Among the key preconditions for transformational changes in certain periods are: rapid deterioration of key macroeconomic indicators, implementation of laws and regulations on the establishment of the tax police and the transformation of the State Tax Administration into a central executive body as a controlling body for legal entities and individuals, changes in the composition and mechanisms of tax calculation, chaos and invalidity of the system of tax benefits, changes in the legalization of the wage fund and in the system of compulsory state social insurance. The functions of taxes as defining concepts of formation of the tax system of the country that were in each period defined above are investigated. The types and role of tax relief as a tool of state tax regulation and stimulation of socio-economic processes are considered. The assessment of the process of transformation of the tax system identified the existing criteria for reform, including diversity, complementarity and consistency, compromise and evolution, the depth of transformation and innovation of the tax system of Ukraine. It is proved that the tools of transformation of the implementation of the taxation system of Ukraine used in these processes did not always correspond to the peculiarities of the socio-economic situation of the country and the tax policy of the state goal and set of tasks of economic strategy. Existing shortcomings in the Ukrainian taxation system hinder economic growth and lead to high economic shadowing. Thus, the application of these tools in the process of transformation of the tax system has partially solved the existing problems, a significant number of identified tasks currently remain unresolved. Keywords: taxation system, taxes, tax deductions, the state budget, taxation. JEL Classification E62 Formulas: 0; fig.: 0; tabl.: 1; bibl.: 18.

The study of egg-laying patterns and defining ways of increasing egg-laying productivity is a necessary condition for the development and increased efficiency of ostrich breeding. Therefore, some studies deal with egg productivity of ostriches of different age groups (group 1 - age 8-9 years, group 2 - age 4-5 years) for their long-term keeping under a semi-intensive system forest-steppe zone of Ukraine. The sex ratio in the families was 1: 2-3. Behavioral patterns of poultry during the breeding season are close to natural ones. Older individuals are characterized with a longer productive period (January-October) than younger ones (March-September). According to the most extended daylight hours at this time of year, the higher level of egg-laying performance is established in May and summer months. The females’ egg-laying performance analysis shows their significant individual features - 9-42 eggs were obtained from one female. It is worth mentioning that the productivity period’s duration does not continuously regulate the number of eggs. There is a high positive correlation between the duration of the egg-laying process and total egglaying performance in group 1 (r = 0.7981); in group 2 � there is no relation between these features (r = -0.0843). The variability of egg-laying cycles of ostrich females has been confirmed, and it requires further studies. According to the intensity of lying during the breeding season, there are differences between younger and older poultry groups. The first two months and the last month of egg-laying are the least productive for all. It was established that the egg weight of older females is higher compared to young ones, with a potential difference between the groups (P> 0.999) and a significant level of individual variability (Cv = 1.78-8.06%). This indicates the necessity of successive work with the herd to optimize egg weight, as a significant variation in egg weight affects the duration of incubation and embryonic development of ostriches. It also leads to the elongation of the “hatch window” that causes heterogeneity of ostrich weight. New data allow characterizing the peculiarities of ostrich physiology, their ability to adapt to industrial conditions of breeding at farms located in the northern part of the forest-steppe zone of Ukrai.

The role that hydropower plays in the world’s energy balance is considered, and a comparative analysis of using hydropower resources in Russia and abroad is presented. It is shown that Russia occupies the world’s second place in its hydropower potential after China; however, no more than 20% of the country’s hydraulic power resources have presently been harnessed. This is significantly lower than in Germany, France, Sweden, and Japan, countries in which 65–90% of their available hydraulic power resources are used. In view of a great variety of natural conditions, turbines of different types are used in the hydraulic power industry. It has been determined that the power performance indicators (efficiency and capacity) of the hydraulic machines that are presently produced in Russia correspond, as in the years of the former Soviet Union, to world-class standards. Trends in the development of hydropower and construction of hydraulic turbines are analyzed. It is shown that, given insignificant scales of constructing new hydroelectric power plants in Russia, replacement of the equipment at the existing hydroelectric power plants that had worked out its standard service life long ago is the industry’s main development line for the nearest (10–15 years) future. The need to replace the operating hydraulic machines mainly stems from inefficient utilization of water stream at the existing hydroelectric power plants. It is pointed out that, despite the emerged tendency toward decreasing the reliability of hydraulic power units that have been in operation for a long period of time, its catastrophic drop is not observed at any of the examined hydroelectric power plants even though their machines have been in operation for twice as much as their standard service life (30 years) or even more. Refurbishment of the machines makes it possible and shall mandatorily improve the power performance characteristics of the machines, resulting in an increased power capacity or improved efficiency (of energy generation). An improvement in the power performance characteristics of new hydraulic turbines is achieved almost solely due to the use of more advanced runners while keeping the other flow path elements unchanged.

The discrete sensors of continuous physical quantities are widely used in various technical systems. Real sensors have a considerable inertia and they operate in the conditions of random noises, therefore, they include the analog-to-digital interface. This interface creates discrete values of the input signal and suppresses the influence of random noises almost completely with application of the antialiasing filter. However, the discrete values are formed on the output of the analog-to-digital interface with some time delay. Therefore, the digital sensors have a large error, caused by this delay. In this article to eliminate this error an astatic high-speed discrete corrector is proposed. The error of the corrected discrete sensor is equal to zero at the steady-state mode, if the degree of the input polynomial signal is one unit less than the astatism order of the used corrector. It is supposed that the time delay of the discrete sensor is multiple to the sampling period of the analog-to-digital interface. To determine transfer functions of the discrete sensor and the astatic discrete corrector the formulas are obtained. The operation algorithm of the astatic high-speed discrete corrector is determined on the basis of its transfer function. The efficiency and feasibility with application of digital device of the proposed corrector is illustrated by the example of the sensor design with the astatism of the second order. The obtained results can be used in the development of highly precise discrete sensors of various physical quantities.

Background. Bisphosphonates have become a common method for the prevention and treatment of osteoporosis in children with neuromuscular diseases. Aim. The aim of this study was to assess the mid-term changes of bone mineral density in patients with cerebral palsy and spina bifida treated with ibandronic acid. Materials and methods. Thirty-four patients were examined and treated: 19 children with cerebral palsy (GMFCS levels IIIIV) and 15 children with spina bifida (thoracic and upper lumbar neurosegmental levels), mean age 9.8 2.9 years. Ibandronic acid was administered to all patients (3 consecutive intravenous infusions, 0.1 mg/kg every 34 months). The assessment of bone mineral density was performed using dual-energy X-ray absorptiometry. Results. The Z-score increased from 2.55 to 2.1 (total body less head), and from 2.7 to 1.65 (lumbar spine). Improvement of the Z-score for the lumbar spine was noted after the first infusion, and for the whole body after the first two infusions. Conclusion. Ibandronic acid infusions improved the bone mineral density in children with cerebral palsy and spina bifida for both the whole body and the lumbar spine. Given the data obtained, weight-bearing exercises can be recommended three months after the first infusion, and dynamic exercises can be performed, preferably after six months.

Equipment of the Krasnoyarsk HPP is considered as an example to analyze the dependence of crack formation in runner blades on the operating conditions of the turbines since their commissioning. It was established that intensive crack formation in blades in the initial (running-in) period was due to manufacturing-induced high residual stresses and internal material defects. The blade failure rate increased with water head and, hence, the output of the hydroelectric units. The absence of cracks in the blades today indicates that the lifetime of the runners has not ended yet.

Inadequate efficiency with which the energy of water flow is used is the basic reason why it is necessary to reconstruct hydraulic turbine equipment with lengthy service life. Hydraulic turbines constructed in the Soviet period are characterized by high reliability indicators even after 50 – 60 years of service, i.e., the age of hydraulic units does not play a decisive role in reducing the reliability of equipment.

Backgrоund. Osteoporosis is an important factor in the pathogenesis of orthopedic manifestations in children with cerebral palsy. It was previously demonstrated that children with cerebral palsy have specific changes in bone metabolism, which can cause changes in laboratory parameters compared with other orthopedic patients without neurological backgrounds. Aim. The aim of this study was to assess bone metabolism biomarkers in children with cerebral palsy, identifying distinguishing characteristic patterns in comparison with patients with orthopedic pathology without neurological backgrounds. Materials and methods. This study evaluated the concentrations of calcium, phosphorus, -cross laps, osteocalcin, vitamin D, CICP, and alkaline phosphatase in the blood serum of 50 children with cerebral palsy aged between 6 to 12 years with GMFCS levels IIII. The control group consisted of 50 patients with plano-valgus deformities of the feet. Results. The alkaline phosphatase activity in the group of children with cerebral palsy was 170.25 59.35 u/L, while in the control group it was 145.58 46.29 u/L; the CICP concentration in the study group was higher than in the control group (324.01 174.10 and 269.68 240.98, respectively). The concentration of -cross laps, osteocalcin, calcium, and vitamin D in the study group was lower than in children with flat feet. Conclusions. This study demonstrated multidirectional changes in the biomarkers of bone metabolism that are characteristic of walking children with cerebral palsy. These changes are characterized by a corresponding increase in the activity of osteoresorption and osteoreparation. This makes it possible to justify the combined use of metabolites and metabolic activators (calcium and vitamin D) and drugs that suppress osteoresorption (bisphosphonates) for the prevention and treatment of osteoporosis in children with cerebral palsy.

In the article, according to international statistics (FAOSTAT), the dynamics of the duck population and the production of duck meat in the world, in Ukraine and in certain countries in the period 2016-2020 are given. It is established that in 2020 the duck population in the world slightly decreased (by 0.75%). At the same time, the largest number of ducks is concentrated in China – 62.7 and 60.6% of the world's population, respectively, in 2016 and 2020. Ukraine took tenth place in this ranking in 2020. With a slight fluctuation in the number of ducks in the world, a tendency to its increase was noted in the production of meat – by 37.8% compared to 2016. However, in Asian countries, ducks are bred not only for meat, but also for eggs, which are used as food. Duck egg consumption is about 10-30% of total egg consumption in China and Southeast Asia. Among the population of South-East Asian countries, such a product as "balyut" is popular, which is prepared using a duck egg with an embryo about 18 days old. Based on the analysis of data from various literary sources, the issue of duck keeping systems in different countries of the world and Ukraine is highlighted. Since ducks belong to waterfowl, along with the intensive technology of keeping them (in closed rooms with a microclimate that is controlled and regulated), extensive technology is also used – using walks, including water ones. In Ukraine, 97.5% of the duck population is kept in public farms, and therefore the main system of their keeping is extensive. The importance of complete feeding of ducks is also indicated, recommendations are given regarding the nutritional value of rations depending on the age of the bird. In Ukraine, the largest farm engaged in the industrial production of duck meat is the Poultry Brood Plant “Korobivskyi” JLLC of the Zolotonosha district of the Cherkasy region. The production of duck meat using intensive technology involves the use of high-production crosses, the keeping of poultry in poultry houses with a regulated microclimate and complex mechanization and automation of technological processes, and the feeding of poultry with complete ration compound feed.

We have developed technology and construction solutions system to increase differential pairs (DP) of JFet with p- and n-channels identity, which are included into silicon complementary bipolar process of SPE “Pulsar” (Moscow). The possibility of creating several types of JFet DPs within the process is shown. The paper presents the results of experimental studies of two types of DP JFet designs with p- and n-channels for the spread of gate-source voltage ΔVGS depending on the drain current and drain-source voltage. The main features of the first design of p-channel JFets were the following: formation of drain/source area due to passive base of npn-transistor and deep collector areas for pnp-transistor; channel formation based on p-layer collector of pnp-transistor; formation of bottom gate using p+ buried layer; top gate formation due to active base and polysilicon emitter of npn-transistor. A feature of the second JFet design was top gate formation due to passive base. The designs of the first and second types of n-channel Jfet were formed similarly, taking into account the replacement of the applied areas of bipolar transistors with opposite ones in the type of conductivity. It was found that with increasing drain current ΔVGS decreases, and with increasing drain-source voltage ΔVGS at high currents increases for DP based on p-channel JFet with the first type of design. The maximum difference ΔVGS was in the range of 5–80 mV for a given differential pair JFet with a p-channel. On plots for DP p-channel JFet with the second type design a significantly lower voltage spread ΔVGS was shown: for example, for the drain current ID = 50 μA the voltage spread ΔVGS did not exceed 10mV. In this case the voltage spread ΔVGS practially did not depend on drain-source voltage in contrast to differenctial pair of the first type. The second type JFet n-channel differential pairs like for the DP p-channel JFet provided lower spread values in comparison with the first type design: ΔVGS reached values of 5-20 mV. Moreover, for the design of the second type, a significantly weaker effect of the drain-source voltage on ΔVGS was observed at high current densities. The developed designs of differential pairs based on p- and n-channel JFet are recommended for use in organizing the production of CBiCJFet analog circuits, including operations at low temperatures., Разработана система технологических и конструктивных решений, обеспечивающая повышение идентичности дифференциальных пар (DP) полевых транзисторов с управляющим p-n переходом (JFet) с p- и n-каналами, встроенных в кремниевый комплементарный биполярный технологический процесс АО «НПП «Пульсар» (г. Москва). Показано, что в рамках данного технологического процесса возможно создание нескольких типов DP JFet. В работе представлены результаты экспериментальных исследований двух типов конструкций DP JFet с p- и n- каналами по разбросу напряжения затвор-исток ΔVGS в зависимости от тока стока и напряжения сток-исток. К основным особенностям первой конструкции p-канального Jfet относились: формирование областей стока/истока за счёт пассивной базы npn-транзистора и областей глубокого коллектора pnp-транзистора; формирование канала на основе p–слоя коллектора pnp-транзистора; формирование нижнего затвора с применением p+ скрытого слоя; формирование верхнего затвора за счёт активной базы и поликремниевого эмиттера npn-транзистора. Особенностью второй конструкции Jfet являлось формирование верхнего затвора за счёт пассивной базы. Конструкции первого и второго типов n-канальных Jfet формировались аналогично с учетом замены применяемых областей биполярных транзисторов на противоположные по типу проводимости. Для DP на основе p-канальных JFet с конструкцией первого типа установлено, что с ростом тока стока величина ΔVGS снижается, а с увеличением напряжения сток-исток ΔVGS при высоких токах возрастает. Для данной дифференциальной пары JFet с p-каналом максимальная разница DVGS лежит в пределах 5–80 мВ. Для DP p-канальных JFet с конструкцией второго типа приведены графики, показывающие существенно меньшее значение разброса напряжений ΔVGS: например, для значения тока стока ID = 50 мкА разброс напряжений ΔVGS не превышает 10 мВ. При этом, в отличие от первого типа DP, разброс напряжения ΔVGS практически не зависит от напряжения сток-исток. Как и для DP p-канальных JFet дифференциальные пары n-канальных JFet второго типа обеспечили меньшие значения разброса в сравненни с конструкцией первого типа: ΔVGS достигает значений 5 – 20 мВ. Также для конструкции второго типа наблюдалось значительно более слабое влияние напряжения сток-исток на ΔVGS при высоких плотностях тока. Разработанные конструкции дифференциальных пар на основе p- и n-канальных JFet рекомендуется использовать при организации производства CBiCJFet аналоговых микросхем, в том числе для эксплуатации в условиях низких температур., Розроблено систему технологічних і конструктивних рішень, що забезпечує підвищення ідентичності диференціальних пар (DP) польових транзисторів з керуючим p-n переходом (JFet) з p- і n-каналами, що вбудованих в кремнієвий комплементарний біполярний технологічний процес АТ «НВП «Пульсар». Показано, що в рамках даного технологічного процесу можливе створення декількох типів DP JFet. В роботі представлені результати експериментальних досліджень двох типів конструкцій DP JFet з p- і n- каналами з розкидом напруги затвор-витік ΔVGS в залежності від струму стоку і напруги стік-витік. До основних особливостей першої конструкції p-канального Jfet ставилися: формування областей стоку / витоку за рахунок пасивної бази npn-транзистора і областей глибокого колектора pnp-транзистора; формування каналу на основі p-шару колектора pnp-транзистора; формування нижнього затвору з застосуванням p+ прихованого шару; формування верхнього затвору за рахунок активної бази і полікремнієвогох емітера npn-транзистора. Особливістю другої конструкції Jfet було формування верхнього затвору внаслідок пасивної бази. Конструкції першого і другого типів n-канальних Jfet формувалися аналогічно з урахуванням заміни застосовуваних областей біполярних транзисторів на протилежні за типом провідності. Для DP на основі p-канальних JFet з конструкцією першого типу встановлено, що зі зростанням струму стоку величина ΔVGS знижується, а зі збільшенням напруги стік-витік ΔVGS за великих струмах зростає. Для даної диференціальної пари JFet з p-каналом максимальна різниця ΔVGS лежить в межах 5 - 80 мВ. Для DP p-канальних JFet з конструкцією другого типу наведено графіки, що показують істотно менше значення розкиду напруг ΔVGS: наприклад, для значення струму стоку ID = 50 мкА розкид напруг ΔVGS не перевищує 10 мВ. При цьому, на відміну від першого типу DP, розкид напруги ΔVGS практично не залежить від напруги стік-витік. Як і для DP p-канальних JFet диференціальні пари n-канальних JFet другого типу забезпечили менші значення розкиду в порівнянні з конструкцією першого типу: ΔVGS досягає значень 5 - 20 мВ. Також для конструкції другого типу спостерігалося значно слабший вплив напруги стік-витік на ΔVGS у разі високої щільності струму. Розроблені конструкції диференціальних пар на основі p- і n-канальних JFet рекомендується використовувати при організації виробництва CBiCJFet аналогових мікросхем, в тому числі для експлуатації в умовах низьких температур.

A new notch filter (NF) circuit based on a single differential difference operational amplifier (DDA) has been developed and studied, which is characterized by reduced current consumption in the static mode. Equations are obtained for the transfer functions and parameters of the NF, which includes a low-pass filter and a Sallen-Key high-pass filter, the signals of which are summed by the DDA. Computer modeling of the NF in CAD Micro-Cap was performed.

A new high-pass filter (HPF) circuit of the second-order Sallen-Key family has been developed and studied, in which independent adjustment of the main parameters is realized -the pole frequency, the quality factor of the pole and the transmission coefficient. The basic equations for the transfer functions and HPF parameters are presented. The results of computer simulation a proposed circuits HPF in CAD Micro-Cap 12 are shown.

The generalized structure of the second-order RC filters (LPF, HPF, BPF) with independent setting of the basic parameters - pole frequency, pole Q-factor and transfer ratio is considered. From these positions, the requirements for three special transfer functions (TF) of the multipole of the frequency-setting RC circuit, which contains two resistors and two capacitors, are formulated. The type of the required filter (LPF, HPF, BPF) is implemented by selecting the coefficients of the numerator of the first TF. The coefficients of the second TF are chosen so that that they only affect the pole frequency. In this case, the choice of the parameters of the third TF provides the required pole attenuation. The stages of synthesis of the ARCFs of this class, the existence of which is confirmed by 14 patents of the Russian Federation, are considered.

Current mirror (CMs) are the basis of many analog integrated circuits. In this case, the systematic component of the zero bias voltage and the input common-mode rejection ratio of operational amplifiers, comparators, etc. largely depends on the current gain (K i ) of the CMs used in them, that is, the differences between K i and unity. The article presents the circuitry fundamentals of precision low-temperature CMs for JFET/ CJFET operational amplifiers, providing the ability to obtain both inverting and non-inverting K i values (+1, +2, +3, -1, -2). Non-inverting CMs with $\mathrm{K}_{\mathrm{i}}=1\div 3$ are in demand in active RC filters of the Sallen-Key class. Due to the use of JFET transistors, the proposed CMs operate in the low temperature range (up to -197°C), as well as with a neutron flux up to 1014n/cm2. Computer simulation of the developed CMs, performed in the LTSpice XVII environment on complementary field-effect transistors with a control pn junction of JSC “Integral” (Minsk, Republic of Belarus) and confirms the high precision of the considered CMs in a wide range of input currents.

This paper proposes operational amplifier’s (Op-Amps) architectures based on complementary field-effect transistors with p-n junction (CJFETs), in which the effect of channel length modulation on the systematic component of the Op-Amp’s zero offset voltage (V off ) is reduced. The peculiarity of the developed Op-Amp’s circuitry solutions is that due to the high self-adjusting symmetry of the static mode in terms of the gate-drain voltages of the dominant CJFETs, they provide a low V off level and increased values of the gain (GAIN). The computer simulation of Op-Amps in the LTSpice software (Analog Device, USA) showed that GAIN of the Op-Amps is more than 80 dB, and the systematic component of the zero offset voltage is within 30 μV in the temperature range up to -197°C. Op-Amp circuits of the proposed subclass can have low current consumption in static mode and can be performed not only on Si CJFETs, but also on the basis of wide-gap semiconductors (SiC CJFET, GaN CJFET or GaAs CJFET). Recommended applications of the developed architectures are analog interfaces of physical quantities of sensors for high-energy physics, medicine, and space instrumentation.

A perspective stabilization method for the static mode of a “floating” input differential stage in an op-amp based on complementary field-effect transistors with a control p-n junction (CJFet) is considered. The method provides small values of the systematic component of the offset voltage $(\mathrm{V}_{\mathrm{o}\mathrm{s}})$, as well as increased values of the voltage gain (A 0 ) and the input common-mode rejection ratio (CMRR) without the use of classical current mirrors. The mathematical analysis is presented, which confirms the results of computer simulation of the op-amp on the models of CJFet transistors of JSC“Integral” (Minsk, Republic of Belarus). The structure of a CAD-system is considered, which allows solving problems of both local and global multicriteria and parallel optimization of analog microcircuits in the LTspice environment on a multicore processor, as well as distributed optimization on clusters of weak computer systems. In the LTspice environment, parametric optimization of the proposed op-amp was performed, which made it possible to reduce $\mathrm{V}_{\mathrm{o}\mathrm{s}}$ by more than 1000 times to a level of 10-100$\mu$V when exposed to radiation and cryogenic temperatures, as well as to obtain the voltage gain of an open op-amp of about 120 dB with one highimpedance node.

New structured array (SA) MH2XA020 and the way of designing nuclear electronic integrated circuits (ICs) based on it are considered. The SA MH2XA020 contains eight readout channels. Each channel includes a charge-sensitive amplifier (CSA), an amplifier-shaper (AS) with gain control and “tail” cancellation, a sampling and storage device (SSD), and a multiplexer. In the SA, it is possible to change the operating current of the input transistor, RC value in the CSA feedback loop, and the peaking time of the AS. Experimental results of eight-channel MH2XA020-01 chip implemented on the SA are presented.

The implementation of a charge-sensitive amplifier (CSA) based on the МН2ХА030 array chip (AC) with an adjustable conversion factor for processing signals of silicone photomultipliers (SPM) is considered. The developed CSA, named ADPreampl3, contains a fast and slow signal circuit (SC). The fast SC includes a transresistive amplifier-shaper with a base-level adjustment circuit, and a slow SC includes an CSA, a shaper, and a base-level restorer (BLR) circuit. The main advantage of ADPreampl3 amplifier when used in multichannel integrated circuits is the minimum number of elements used, due to the use of the same stages to perform different functions. To correctly simulate the operation of ADPreampl3, taking into account the features of the input signal source, a simplified electrical equivalent circuit of the SPM, applicable to both circuit simulation and measurements, is proposed. Circuit simulation of ADPreampl3 using the proposed equivalent circuit of SPM with a supply voltage of ±3 V, made possible to establish that: fast SC is characterized by the bandwidth up to 60 MHz and allows adjusting the base level in the range from -0.1 V to 0.2 V. Thus, it is possible to compensate the technological variation of the output voltage of the fast SC or set the required switching threshold of the comparator connected to the output of the fast SC; slow SC allows you to adjust the base level in the range from -1 V to 1 V and smoothly change the amplitude of the output signal, including phase inversion, when the control voltage changes from -1 V to 1 V; the BLR circuit provides a constant shape of the output voltage pulse with a DC input current of ADPreampl3, varying in the range of ±190 μA, and a negligible change of the base level at ±20% of the resistance variation of integrated resistors. ADPreampl3 amplifier enables the transition to the ``sleep'' mode with a decrease in current consumption up to 10 μA, maintains operability at an absorbed dose of gamma radiation up to 500 krad and the effect of the integral neutron fluence up to 1013 n/cm2 and can be used in multi-channel signal processing chips of SPM., Рассмотрена реализация на базовом матричном кристалле МН2ХА030 зарядочувствительного усилителя (ЗЧУ) с регулируемым коэффициентом преобразования, предназначенного для обработки сигналов кремниевых фотоэлектронных умножителей (SiФЭУ). Разработанный ЗЧУ, названный ADPreampl3, содержит быструю и медленную сигнальную цепь (СЦ). Быстрая СЦ включает трансрезистивный усилитель-формирователь со схемой подстройки базового уровня, а медленная СЦ - ЗЧУ, формирователь, схему восстановления базового уровня (ВБУ). Главным преимуществом усилителя ADPreampl3 при его применении в многоканальных ИС является минимальное количество используемых элементов, обусловленное применением одних и тех же каскадов для выполнения разных функций. Для корректного моделирования работы ADPreampl3 с учетом особенностей источника входного сигнала предложена упрощенная электрическая эквивалентная схема SiФЭУ, применимая как для схемотехнического моделирования, так и для измерений. Схемотехническое моделирование ADPreampl3 с использованием предложенной эквивалентной схема SiФЭУ при напряжении источников питания, равном ± 3 В, позволило установить, что: - быстрая СЦ характеризуется полосой пропускания до 60 МГц и позволяет подстраивать базовый уровень в диапазоне от -0,1 В до 0,2 В. Таким образом возможна компенсация технологического разброса выходного напряжения быстрой СЦ или установка требуемого порога переключения компаратора, подключаемого к выходу быстрой СЦ; - медленная СЦ позволяет регулировать базовый уровень в диапазоне от -1 В до 1 В и плавно изменять амплитуду выходного сигнала, включая инверсию фазы, при изменении управляющего напряжения от -1 В до 1 В; - схема ВБУ обеспечивает неизменную форму выходного импульса напряжения при постоянном входном токе ADPreampl3, изменяющемся в диапазоне ± 190 мкА, и пренебрежимо малое изменение базового уровня при ± 20 % разбросе сопротивлений интегральных резисторов. Усилитель ADPreampl3 допускает переход в "спящий" режим с уменьшением тока потребления до 10 мкА, сохраняет работоспособность при поглощенной дозе гамма-излучения до 500 крад и воздействии интегрального потока нейтронов до 1013н/см2 и может найти применение в многоканальных микросхемах обработки сигналов SiФЭУ., Розглянута реалізація на базовому матричному кристалі МН2ХА030 зарядочутливого підсилювача (ЗЧП) з регульованим коефіцієнтом перетворення, призначеного для обробки сигналів кремнієвих фотоелектронніихпомножувачів (SiФЕП). Розроблений ЗЧП, названий ADPreampl3, містить швидку і повільну сигнальне коло (СК). Швидке СК включає трансрезістівний підсилювач-формувач зі схемою підстроювання базового рівня, а повільне СК - ЗЧУ, формувач, схему відновлення базового рівня (ВБР). Головною перевагою підсилювача ADPreampl3 у разі його застосуванні в багатоканальних ІС є мінімальна кількість використовуваних елементів, що обумовлено застосуванням одних і тих же каскадів для виконання різних функцій. Для коректного моделювання роботи ADPreampl3 з урахуванням особливостей джерела вхідного сигналу запропонована спрощена електрична еквівалентна схема SiФЕП, що використовується як для схемотехнічного моделювання, так і для вимірювань. Схемотехнічне моделювання ADPreampl3 з використанням запропонованої еквівалентної схема SiФЕП у разі, якщо напруга джерела живлення дорівнює ± 3 В, дозволило встановити, що: - швидке СК характеризується пропускною здатністю до 60 МГц і дозволяє підлаштовувати базовий рівень в діапазоні від -0,1 В до 0,2 В. Таким чином можлива компенсація технологічного розкиду вихідної напруги швидкого СК або установки необхідного порогу перемикання компаратора, що підключається до виходу швидкого СК ; - повільне СК дозволяє регулювати базовий рівень в діапазоні від -1 В до 1 В і плавно змінювати амплітуду вихідного сигналу, включаючи інверсію фази, у разі зміни керуючої напруги від -1 В до 1 В; - схема ВБП забезпечує незмінну форму вихідного імпульсу напруги при постійному вхідному струмі ADPreampl3, що змінюється в діапазоні ± 190 мкА, і не впливає мала зміна базового рівня у разі відхилення значень опорів інтегральних резисторів ± 20%. Підсилювач ADPreampl3 допускає перехід в "сплячий" режим зі зменшенням струму споживання до 10 мкА, зберігає працездатність під час поглинення дози гамма-випромінювання до 500 крад і впливі інтегрального потоку нейтронів до 1013 н/см2 і може знайти застосування в багатоканальних мікросхемах обробки сигналів SiФЕП.

The main designs of low-sensitivity multiloop active RC filters (ARCFs) based on micropower operational amplifiers (OAs) for preliminary sensor signal processing in microelectronic measuring systems with analog-to-digital converters are discussed. Thirteen modifications of the integrators included in the active RC filter structure are presented and classified. The equations for their transfer functions, which take into account the effect of the integrator topology and the amplification area of micropower OAs, are obtained. As an example, the frequency responses of three universal low-sensitivity ARCF circuits for implementing bandpass, high-pass, and low-pass filters are compared. It is shown by computer simulation that the investigated ARCFs based on identical micropower OAs differ from each other in the effect of the amplification areas of the OAs on the implemented frequency responses.

A new circuit of a fourth-order band-pass RC-filter (BPF) which provides independent adjustment of the main parameters is investigated: the irregularity of frequency characteristic (FC), the bandwidth and the scale transfer coefficient. An algorithm for choosing the circuit parameters to achieve a given accuracy of digital potentiometers is described. The transfer functions of the developed BPF are presented and the frequency response obtained as a result of computer simulation in CAD Micro-Cap is shown.

The new circuit of fourth-order band-pass filter (BPF) has been developed with independently adjustable parameters - non-uniformity of the amplitude-frequency characteristic (AFC), bandwidth and transmission scale factor. The basic mathematical expressions for transfer function coefficients of the BPF structure and their parameters of AFC are presented. The AFCs was show from program Micro-Cap.