The design of radiation-hardened circuits the use of special technologies and the use of additional circuit techniques. The efficiency of using these methods to improve the scheme qualitative indicators can be assessed by some evaluation. The paper presents the efficiency evaluation method of special voltage feedbacks application in dynamic loads of the classical differential stages. The stages with dynamic loads are apply, for example, in the schemes of differential and multidifferential operational amplifiers. The purpose of the introduction of these feedbacks is the reducing of the effect of transistors low-signal parameters instability under the influence of destabilizing factors (radiation and temperature). For the organization of feedback circuits in the structure of dynamic loads, additional voltage amplifiers based on transistors are introduced into the circuit. It is shown that this approach can increase the output resistance of the dynamic load and increase the gain coefficient of the differential stage under the influence of ionizing radiation and temperature. The efficiency evaluation method is based on the construction of a mathematical model of the scheme expressed through low-signal differential h-parameters of scheme transistors. Thus, the calculation of the main qualitative indicators of the scheme can be carried out by mathematical modeling. The obtained simulation results confirm the efficiency of the proposed circuit design.

Keywords: efficiency evaluation, circuit design, dynamic load, low-signal parameters, radiation

This paper presents a radiation hardened by design of differential stages using dynamic loads. The efficiency of proposed design methods to improve the scheme qualitative indicators can be assessed by some evaluation. The theoretical results of the evaluation of the self-compensation circuit effect of parasitic impedance of the output transistor closed collector in the dynamic loads of classical differential stages, which is realized on the base of current feedbacks, are presented. It is shown that the introduction of the current feedbacks allows to reduce the effect of transistors small-signal parameters instabilities of the dynamic load under the influence of ionizing radiation and temperature on it's quality and the parameters of the differential stages. The efficiency evaluation of the circuit solutions in differential stages of modern operational and multidifferential amplifiers is given. The theoretical results of the evaluation of the self-compensation circuit effect of parasitic impedance of the output transistor closed collector in the dynamic loads of classical differential stages, which is realized on the base of current feedbacks, are presented. It is shown that the introduction of the current feedbacks allows to reduce the effect of transistors small-signal parameters instabilities of the dynamic load under the influence of ionizing radiation and temperature on it's quality and the parameters of the differential stages. For the organization of feedback circuits in the structure of dynamic loads, additional current amplifiers based on transistors are introduced into the circuit. It is shown that this approach can increase the output resistance of the dynamic load and increase the gain coefficient of the differential stage under the influence of ionizing radiation and temperature. The efficiency evaluation of the circuit solutions in differential stages of modern operational and multidifferential amplifiers is given. The efficiency evaluation method is based on the construction of a mathematical model of the scheme expressed through low-signal differential h-parameters of the scheme transistors. Thus, the calculation of the main qualitative indicators of the scheme can be carried out by mathematical modeling. The obtained simulation results confirm the efficiency of the proposed circuit design.

Keywords: efficiency evaluation, circuit design, differential stage, dynamic load, destabilizing factors, low-signal parameters

The development of electrochemical impedance spectroscopy method in the field of high-frequency signals is proposed using an amplitude-phase approach to analyze the parameters of various biological sensors. Unlike the standard high-frequency analog electrochemical impedance spectroscopy systems interfaces based on quadrature demodulation, the use of peak and phase detectors allows improving the basic metrological parameters, as well as simplifying the analog interface with a wide bandwidth of the biological sensor interrogation signal. The circuit design of the phase detector, as part of the general system, is considered on the components of the technological process TSMC 0.35um SiGe. The key feature of this block is the maximum speed due to the rejection of feedbacks. A large range of output voltages and a low speed of their change allow the use of standard analog input modules for inputting phase detector signals to a computer for subsequent digital processing. The final accuracy of biological sensor signal phase detection is maintained at an acceptable level due to the introduction of additional elements in the basic circuit and the digital algorithms presented in the work. The shown variant of carrying out the correction has immunity to nonlinearities of the output characteristic of phase detection for large phase deviations of the signal of the biological sensor. The process technology used in the design is classified as economical, which makes it possible to potentially reduce the electrochemical impedance spectroscopy systems cost of production and introduction of a mass application.

Keywords: biological sensor; impedance spectroscopy; phase detector; quadrature representation of a signal, digital correction, algorithm of data processing, SiGe-technology, system on chip, microwave range, analog interface

`

Keywords: