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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.

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 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.

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.

Two modifications of the second-order multifunctional active filters (ARCF) with a minimum number of passive and active elements have been developed. The proposed ARCF circuits are implemented on differential difference operational amplifiers and have extended frequency range. The basic equations and the results of computer simulation are presented, showing that the first circuit implements realize rejected filter (RF), band-pass filter (BPF) and low-pass filter (LPF), the second circuit implements - high-pass filter (HPF), BPF and LPF.

The circuit simulation results of the charge-sensitive amplifiers (CSA) with various types of input field-effect transistors (FET) are considered. CSA-1 and CSA-2 are implemented on Si bipolar transistors, besides in CSA-1 the input transistor is a Si field-effect transistor with p-n junction (Junction Field Effect Transistor, JFET) and in CSA-2 - a GaAs FET with a gate formed by Schottky contact (metalized semiconductor FET, MESFET). CSA-3 is developed completely on the GaAs MESFET. In order to adequately compare the CSAs with respect to the rise-time τ of the output pulses and the equivalent noise charge (ENC), all input transistors were selected with approximately equal drain current and the ratio of the gate width to the length W/L. The electrical circuits of the CSAs, the simulation results of the operating mode, the critical parameters, the dependence of τ and the ENC on the capacity of the input signal source C D are presented.

Two promising modifications of the multi-functional programmable active filters (PAF) are developed and investigated. The proposed PAF circuits of second order are implemented on the operational amplifiers and have an increased stability of the Q-factor. The basic equations and the results of computer simulation are presented, showing that the developed circuits implement band-pass filters (BPF), low-pass filters (LPF) and high-pass filters (HPF). New modifications of the PAFs allow resetting of the pole frequency using resistor arrays R-2R or digital potentiometer microcircuits. A comparison of the main characteristics of the proposed PAF and the PAF based on famous KHN filters is given.

The structure of the CJFET composite transistor (CT) for JFET technologies (Si, SiC, GaN, GaAs, etc.) is proposed, which in its drain-gate characteristics is similar to a CMOS junction field-effect transistor with an induced channel. The structure of the CJFET CT under consideration has a typical off state zone with a gate-source voltage not exceeding its threshold voltage. When the voltage increases at the equivalent gate, the CT switches to the active mode and can be used in tasks of analog signal amplification. Besides, with respect to the equivalent drain terminal of the CT, the signal is not inverted in the proposed CT. This is its wonderful feature. The main connection silicon circuits of the CT in cryogenic electronics are considered.

The offset voltage (V off ) of the BJT and CMOS two-stage operational amplifiers (Op-Amps) substantially depends on the numerical values (differences from unit) from the current ratio (K i ≈1) of the current mirrors (CM). The CM parameter is also influenced by the Early voltage of their dominant active components. For the JFET technologies (Si, SiC, GaAs and others) with a low noise level, there are no high-quality CMs of this class today, or their construction (at K i =1) is associated with a significant deterioration of other parameters of the Op-Amp. Nowadays, the current JFET mirrors are the weakest link in modern JFET analog circuitry and it is impractical to use them in the structure of the JFET Op-Amps. For the first time the article poses and solves the problem of determining the conditions for exclusion of the CMs in the JFET Op-Amp for the case when it is necessary to obtain a small V off . It is shown that for this, three identical reference current sources should be used, which are implemented on the JFET transistors and the local negative feedback resistors. The V off of the Op-Amps with the classical and proposed architectures are compared. The computer simulation results of the offset voltage (V off ) in the LTspice environment are presented, which show that silicon JFet direct coupled Op-Amps without CM have a systematic component of V off at the level of tens to hundreds of microvolts and voltage gain of more than 80 dB in a wide temperature range.

Nowadays, it is urgent to develop a new generation of active RC filters, which allow for independent tuning of the critical parameters. This makes it easier to build new devices. The paper considers the generalized architecture of a new population of active RC band-pass filters (ARCFs) in which the independent adjustment of the critical parameters in the pass band is possible. As an example the equations for the transfer functions and their coefficients for two new ARCF modifications are given, which allow for the parametric synthesis of the definite design solutions. The results of modeling in the Micro-CAP program are discussed, confirming the advantages of the ARCFs of the considered family.

New low-pass filter (LPF) architectures based on differential difference operational amplifiers (DDOA) are studied in this paper. The feature of the proposed LPF is that when tuning the cut-off frequency, the LPF gain remains unchanged at zero frequency. As a tuning element, it is possible to use digital potentiometers. The basic equations for two LPF modifications are presented, which provide parametric synthesis of circuits. The results of computer simulation of tunable responses were given in Micro-cap CAD.

The circuit solutions that provide increase of common-mode rejection ratio (CMRR) and power-supply noises rejection ratio (PSRR) on a basic parameters of input "floating" complementary differential stage (FCDS) are proposed in the article. This subclass of differential stages is different by low noise level, high radiation hardness and ability of work at low temperatures through the use of junction field- effect transistors. The modified FCDS circuit simulating with CJFET transistors models, consider influence of cryogenic temperatures in LTspice simulation software results are showed. They show that CMRR and PSRR are improved by 2-3 orders of magnitude.

In this paper results of design microwave highvoltage complementary bipolar transistor technology process with complementary junction field-effect transistors (CBiCJFET) are presented. Regimes formation of area of complementary junction field-effect transistors with drain-source breakdown voltage U DS > 36 V and cutoff voltage U GS (off) ~1.5 V are defined. Extension of basis of complementary bipolar technology process is provided with inclusion of 3 extra photolithography operations.

We suggest a method to define dispersion for transfer voltage-ampere characteristics (VAC) of JFET differential pairs, which is tested within circuit simulation and measurements of p-JFET parameters, manufactured in JSC "Integral" (Belarus Republic). We define recommendations, how to select operational mode for operational amplifier (OA) input stages JFET differential pair based on the measurements made. Based on experimental studies, we have define recommendations, how to select operational mode for analog sensor interfaces input stages JFET differential pair, including operational amplifiers (OAs).

A brief information on the bipolar field-effect (BiJFET) array chip (AC) MH2XA030, designed to create radiation-hardened and cryogenic analog integrated circuits (ICs) for processing sensor signals, is presented. The features of the radiation-induced alterations in the parameters of bipolar transistors (BJTs), which must be taken into account when designing analog ICs on the AC, are considered. The electric circuits of the developed voltage comparators (VCs), which differ in fast response and power consumption, as well as the simulation results of their static and dynamic parameters on exposure to gamma emission and neutron flux, are presented. The designed VCs can find their application in the devices for space tool engineering and nuclear electronics.

We suggest original circuit of input differential stage (DS) of AB class on a base of complementary field effect transistors with p-n-junction (CJFET). The main application of the DS is low noise analog ICs for operation in low temperatures, including cryogenic temperatures. Special circuit design of DS static mode circuit design and its parametric optimization in LTspice simulation software provide relatively high stability of static mode of input CJFET in wide temperature rage. At the same time, DSs common-mode rejection ratio (CMRR). We show a possibility to update DS circuit design on CMOS transistors.

The main trends in the design of readout electronics chips for silicone photomultipliers (SPM) are analyzed. The results of the circuit design of a charge-sensitive amplifier (CSA) with an adjustable conversion factor and a base line restorer (BLR circuit) for this type of sensor are considered. The electrical circuit of the CSA is shown and its operation is considered in detail. The advantages of the developed CSA with its application in multichannel chips of signal processing of the SPM are described.

A high-speed buffer amplifier (BA) for analog microcircuits on complementary junction field-effect transistors is proposed. The scheme differs from the known circuit solutions by a small number of elements and can operate within the range of cryogenic temperatures. In the LTSpice simulation software, the optimal control parameters were selected using the DEAP (Distributed Evolutionary Algorithm in Python) library of distributed evolutionary calculations and the NSGA-II multi-criteria optimization algorithm. Minimization of offset voltage, static current consumption and dead band width on the amplitude characteristic at low temperatures were chosen as the priority parameters of the control unit.

The design of a new configurable structured array (CSA) is considered. The CSA is intended for development of multichannel (up to eight channels) integrated circuits of the analog interfaces of sensors. An example of operational amplifier is used to show that circuit synthesis with allowance for radiation-induced variations in characteristics of complementary bipolar transistors may provide minor degradation of parameters of the analog ICs after ionizing irradiation. Electrical schemes of the CSA analog components and experimentally measured parameters are presented.

Запропоновано метод розширення дiапазону робочих частот аналогової мiкросхеми регульованого пiдсилювача (РП) за SiGe БiКМОН технологiї з проектними нормами 0,18 мкм. Розроблений РП має лiнiйну (в дБ) характеристику управлiння. Розглядається архiтектура РП i наводяться результати його проектування. Описано властивостi двох модифiкацiй мiкросхеми РП — з класичною корекцiєю амплiтудно-частотної характеристики i з ланцюгом взаємної компенсацiї паразитної ємностi у високоiмпедансному вузлi. Показано, що друге схемотехнiчне рiшення дозволяє збiльшити верхню граничну частоту РП в 1,8-2 рази. The article proposes a method of bandwidth extension of the analog integrated circuit of the variable-gain amplifier (VGA) based on SiGe BiCMOS technology with the rules of 0.18 μm. The designed VGA has a linear (in dB) control characteristic. The authors consider the VGA architecture and present its design outputs. They describe the properties of two modifications of the VGA integrated circuit — with classical correction of the response and with the circuit of the parasitic capacitance cancellation in the high-impedance node. The article shows that the second circuit solution allows increasing the upper frequency limit of the VGA by a factor of 1.8-2. Предлагается метод расширения диапазона рабочих частот аналоговой микросхемы регулируемого усилителя (РУ) по SiGe БиКМОП технологии с проектными нормами 0,18 мкм. Разработанный РУ имеет линейную (в дБ) характеристику управления. Рассматривается архитектура РУ и приводятся результаты его проектирования. Описаны свойства двух модификаций микросхемы РУ — с классической коррекцией амплитудно- частотной характеристики и с цепью взаимной компенсации паразитной емкости в высокоимпедансном узле. Показано, что второе схемотехническое решение позволяет увеличить верхнюю граничную частоту РУ в 1,8-2 раза.

A parametric optimization subsystem (PPS) has been developed that focuses on the use of the LTspice environment for designing low-temperature and radiation-hardened analog microcircuits in space instrumentation tasks. However., local optimization (NM, MAGPM), global optimization (DE, jDE, PSO, SA, ABC), multi-criteria optimization (NSGA-II, SPEA2, MO-CMA-ES), parallel optimization on a multi-core processor, distributed optimization on the cluster of personal computers, plotting the fitness functions and Pareto efficiency, operation with the latest version of LTspice are provided. An example of parameter optimization of the elements of a low-temperature output stage (BA) of an operational amplifier, realized on complementary junction field-effect transistors, is given. A comparison of the characteristics of optimal and non-optimal BA is presented.

The article considers theoretical justification for creating a measuring method for liquid level in tanks containing oil, petroleum products, liquefied gases, etc., by measuring frequency functionally related to the measured level. The novelty lies in the fact that the six-element phasing network of a generator with frequency set in accordance with the measured level is formed by three external resistances and two capacitors. The third capacitor contains two plates: the top plate made of foil-coated fiberglass is located on the floating roof, and the bottom plate is the tank bottom. The microcontroller processes information in accordance with the established algorithm and calibration tables, transmitting level, mass, volume, density and temperature results to the indicator.

The possibility of using a template model for approximation of I- V characteristics of junction field-effect transistors (JFETs) in a wide temperature range (− 200 … 20°C) is considered. The template model is intended for JFETs which are used in radiation-hardened integrated circuits for processing the signals from sensors of various physical quantities. The template model creation is made by the replacement of one or more parameters of the known physical JFETs model by the relations of power series of control voltages. The template model comprises all physical parameters of the initial JFETs model. The number of additional parameters in the template model is small (no more than four), which makes it possible to use standard minimum search algorithms for parametric identification. The obtained results show that the proposed template model provides the decrease of the JFETs I-V characteristics modeling error at least three times in comparison with the initial physical model independently of the measurements temperature.

The article considers a mathematical analysis and computer simulation of total harmonic distortion (THDf)in CMOS differential difference amplifiers (DDA). We have presented THDf's dependence and sensitivity of output voltage in typical DDA circuit to input differential stages (DS)limiting voltage and their static current mode. We have found, that DDA typical circuit's THDf is significantly worse at microamp currents of input CMOS transistors.

The article presents the results of the development of complementary junction field-effect transistors, integrated into the microwave complementary bipolar technological process. The formation modes of the p-channel region of the field-effect transistor, capable of providing a low value of the cutoff voltage and high values of the shorted-gate drain current, are determined. The necessity of applying the methods of suppressing the back diffusion of boron to ensure the cutoff voltage symmetry of the junction field-effect transistors with p- and n-channels is shown.

We have considered results of SiPM analog interface schematic design on array chip MH2XA030. The SiPM includes current buffer, current integrator and base level recovery (BLR) circuit. We have described analog interface operation for this type of sensor in details, specified electrical circuit and computer simulation results.

The article presents a scheme of active RC-filter of the second order (ARCF), which is realized on multidifferential operational amplifiers (DDA). Based on this filter, we can obtain a various amplitude-frequency characteristic (AFC) (low-pass filters (LPF) and high-pass (HPF) filters, band-pass (BPF) and rejection (RF)filters). The main difference between the developed ARCF and the known ones is that when adjusting the quality factor of the pole, their pole frequency and transmission coefficient do not change.

We have considered a modified architecture of the third order low-frequency filter (LFF), intended to be applied as an anti-alias filter on inputs of analog-digital converters (ADC’s) with differential input. We have obtained conditions for low-frequency filter’s circuit parametrical synthesis. We have shown results of suggested LFF simulation and compared its amplitude-frequency characteristics (AFC’s) at different frequencies of applied operational amplifiers’ (OP-AMP’s) unity gain (AD8132, THS4131).

A new structure of the third order low-pass RC-filter (ARCF-III) designed for practical use as a spectrum limiter at the input of various analog-to-digital converters of the A/D Interface of the instrumentation and control system is considered. It is shown that in the proposed ARCF-III the high guaranteed attenuation of the amplitude-frequency characteristic is provided outside the operating band. Three modifications of ARCF-III are developed for its implementation based on differential and differential difference operational amplifiers. Analytical expressions defining the conditions for the synthesis of ARCF-III are presented. The results of computer simulation of the amplitude-frequency characteristic are discussed.

A method is proposed for increasing the guaranteed attenuation of the amplitude-frequency characteristic of the active RC filter (ARCF) for processing piezoelectric signals of sensors outside the band-pass of the desired signal. This effect is provided by the balanced differential input of the ARCF and the original circuit design of its basic functional units. The results of computer simulation and experimental research of the ARCF in the structure of the measuring system of the machine for dynamic of rotors are given, which show that the modified ARCF enable to improve the metrological characteristics of electromechanical balancing systems of this class.

The new structures of the buffer amplifier (BA) and input differential stage (DS) for analog microcircuits and sensor interfaces are considered in the article. These circuit solutions, based on complementary field effect transistors with p-n-junction (CJFet), can be used in CJFet operational amplifiers (Op-Amp), comparators, etc., which are designed for operation at severe conditions. The proposed BA and DS operate in class AB mode, which enables to provide relatively large output currents in dynamic mode (units of milliamperes) at small static currents of transistors (40-100μA). The recommended application areas for BA and DS are analogue sensor interfaces for space instrumentation, high energy physics, and medicine.

In article interrelation of the linear operation range of a CMOS differential difference operational amplifier (DDOA) with the main parameter of the pass characteristics of its input differential stages (DS), the limiting voltage (V lim ), is considered. The results of mathematical and comparative computer modeling of the dependence of V lim typical CMOS DS on the channel width of transistors at different static currents for three CMOS technological foundry processes (0.25 um SiGe CMOS, 0.35um SiGe CMOS and 0.6 um Si CMOS) are presented. Recommendations are given for increasing the maximum slew rate of the output voltage (SR) of the DDOA, which are based on the introduction into each input DS of a differentiating circuit of transient correction.

Active band-pass RC filters (BPF) of the second order on two operational amplifiers have a lot of construction options. The article proposes a new structure of the BPF, which is recommended as a second-order unit included into more complex devices of frequency selection. It is shown that in the BPF under consideration an independent trimming of the main parameters-pole frequency, pole attenuation, and transfer ratio in the bandpass range, is provided. Other known schemes of the BPF do not possess this property.

Features of the schematic design of two types of operational amplifiers (Op-Amp) on the new BiJFet array chip (AC) MH2XA030 are considered. The topology, the electric circuits of the Op-Amp and the results of their computer simulation are given. The brief information about the AC MH2XA030, intended for the accelerated creation of analog integrated circuits (IC) of automation devices, which retain their operational integrity under the influence of penetrating radiation and extremely low temperatures (up to −197°C) is presented.

An unconventional method for increasing the slew rate (SR) of CMOS and BJT operational amplifiers (OPAMP) is considered. In order to obtain a significant gain for the SR (by a factor of 10-100), the parasitic capacitances are used in the common source (emitter) circuit of its input differential stage (DS). The Dual-Input-Stage scheme is applied as a DS. It is shown that the proposed "paradoxical circuitry" works in inverting connections of the OPAMP.

A new integrated circuit (IC) MH2XA010-05, implemented on the structured array (SA) MH2XA010, is considered. It is intended for analog processing of signals of piezoelectric transducers in the system of measuring the gas flow temperature of jet engines by acoustic methods. The electric circuit of the IC is given; the features of functioning and experimental results of measurements of the basic parameters are described.

The article presents the results of process and device modeling results of complementary junction field-effect transistors (JFET). The models necessary for calculating the JFET in the temperature range down to cryogenic were described: the Klaassen model of the carriers mobility (Phillips company model) and Shockley-Read-Hall recombination model, taking into account the doping dependence, Lackner's model of avalanche multiplication, Fermi-Dirac statistics, Slotboom model, designed to describe the dependence of the band gap on the doping concentration. These models take into account the effect of temperature. We have described in detail the model of incomplete ionization of an impurity, which determines the concentration of charge carriers at cryogenic temperatures. The TCAD-based JFET self-heating effect is simulated using a simplified model that significantly reduces the calculation time compared to the thermodynamic model. Studies on the selection of an algorithm for calculating a system of differential equations in the temperature region are carried out. It is shown that the SLIP90 algorithm provides calculations in the entire temperature range down to T = 25 K. The article shows that modification of the design can significantly affect the choice of calculation algorithm. The dependences of the main JFET parameters are analyzed taking into account the selected models on temperature and constructive and technological solutions are proposed to reduce the influence of ultra-low temperatures on the parameters of complementary JFETs.The research results showed that reducing the cut-off voltage reduces the influence of temperature on the shorted-gate drain current JFET in the temperature range. At the same time, n-channel transistors have advantages in terms of a smaller change in parameters over the temperature range down to the temperatures at which the “freezing out” of the impurity charge carriers begins. Several types of transistor topologies were simulated in the temperature range, which showed that the value of the shorted-gate drain current increases linearly with the number of gates. However, there are differences in the dependence of the main parameters in the temperature range depending on the design of the layers of complementary JFETs. Using the emitter region as the top gate weakly affects the parameters of the n-channel JFET in the case of the formation of complementary JFETs in the microwave complementary bipolar technological process, and for the p-channel JFET the temperature stability of the parameters deteriorates. For the p-channel transistor with a gate based on the base region, the temperature stability over the range ΔT = 150–330 K of the shorted-gate drain current is higher than for the transistor with a gate based on the emitter. For the n-channel transistor, the dependence is inverse. Over the range ΔT = 150–77 K, the dependence of the parameters of the transistors for two structures does not differ. In principle, the results show that the change in the ambient temperature has a greater effect on the p-channel transistor than on the n-channel.

A two-channel configured analog microcircuit, intended for applications in optoelectronic devices of space equipment, is created on complementary bipolar transistors. The different combination of microcircuit pins and connection of external RC-elements allow one to create several analog units with specified values of the conversion coefficient of the input signal, bandwidth, rate of rise, and consumed current. The maximal gain of the microcircuit with an open negative feedback loop exceeds 75 dB, and the bandwidth at the 20-fold gain is more than 19.4 MHz. The circuit designs of separate stages of the microcircuit and experimental characteristics are given.

The influence of a 4 MeV energy electron flux and 60Co gamma radiation with an average energy of 1.25 MeV on the characteristics of silicon complementary bipolar transistors (BTs) and a wide-band operational amplifier (OA) has been studied. It is established that an action of FE = 3×1014 el/cm2 electron fluence causes a decay in the common–emitter current gain (s) of 61% for NPN and 66% for PNP transistors, as well as a decrease in the maximum value of the transition frequency (fT) of 12% for NPN and by 4% for PNP transistors. When the absorbed dose DG amounts to 3 Mrad, a decrease in s by 39% for NPN and by 44% for PNP transistors, and in fT of 10% for NPN and 11% for PNP transistors is observed. Despite the substantial decay in s of transistors, the OA circuitry provided the retention of the operation speed and a small decrease in the offset voltage (about 1.5 mV) in the irradiation range mentioned. The circuitries of OA cascades and the experimental characteristics of the BTs and OAs are presented.