SU631944A1 - Arrangement for simulating semiconductor element - Google Patents

Description

The invention relates to radio electronics and may find application in infecting the behavior of radio electronic circuits under the conditions of various destabilizing factors, such as temperature.

A device for modeling transistors containing resistors for modeling passive elements, voltage generators for modeling independent sources of thermal collector current and emitter-base voltage of an equivalent circuit, amplifiers l are known.

The closest in technical essence to the invention is a device for simulating a semiconductor element comprising a voltage generator and a current generator 2j.

The disadvantage of these devices is the low accuracy of the simulation.

The aim of the invention is to improve the accuracy of the simulation.

The goal is achieved in that operational amplifiers, a voltage divider and transistors, a base

ONE of which. The non-inverting inputs of the operational amplifiers, the first:; are covered with a single feedback, and the feedback of the second operational amplifier & l includes a splitter divider; whose output through a voltage generator is connected to the collectors of transistors, the emitters of which are combined, and the current generator is made on a transistor, to the base of which. en-napr51zhenie converter output current.

In the drawing of premsg vaena, the functional diagram of the device is: -a,

The device contains transistors 1.2 operating amplifiers (OA) 3 and 4, a voltage divider, a current generator consisting of an output transistor, to the base of which the output of a voltage-current converter, a voltage generator 7 is connected.

The input signal is fed to the base of transistor 1, which is connected to the non-inverted inputs of the operating amplifiers 3 and 4. The co-pector and the emitter transistor a 1 are connected to the corresponding

by the electrodes of the transistor 2, which is chosen in such a way that the characteristics of both transistors have a minimal difference from the real transistor.

The base transistor 2 is connected to

to the inverting input of the operating line 3 and through the division of 5 voltages to the output of this op-amp. Operational usipntel 4 covered by a single negative back coupling. The outputs of both op-amps are connected to the ACP (with the inverting and non-inverting inputs of the current generator. Since the input impedance of the op-amp 3 and 4 is large, the current flow will flow into the base of the transistor 1 and cause a voltage drop at its base-e-alternate voltage / w) corresponding to the input transistor characteristic.

This voltage through the op-amp 4, covered by a single feedback connection, is fed to the inverting input of the current generator and, amplified by the operational amplifier 3, creates 1 x in the base of the transistor 2. Due to the large gain of the op-amp 3, the voltage on its inverting input is equal to the drop on the input base-emitter junction, n, consequently, a current equal to the input current will go to the base of transistor 2.

Since the base current of the transistor 2 goes through voltage 5 Depth, the potential of the non-inverter of the generator input to the current will differ from the potential of the inverting input by the magnitude of the voltage drop of Egene on the depot of the 5 voltage. Thus, the output current of the current generator will be proportional to the input supper current and on time led the rank of the resistive divider 5 voltage.

Since a current transistor is used as the current generator, the voltage-current converter output is connected to the base, the output characteristics of the model will be determined by the output characteristic of this transistor and will not depend on the value of the resistance of the divider, voltage 5.

Thanks to generator 7, the potential collectors of transistors 1 and 2 will be equal to noTeHUHafjy at the output of the current generator.

i.e. on the collector of the transistor used in the current generator.

When using the device, the base of the transistor 1 is taken as the model base, the current generator 6 serves as the collector of the model, and the emitter point of all the transistors serves as the emitter. Thus, the input and output characteristics of the model are determined by the characteristics of the transistors and do not change when the resistance of the voltage divider 5 changes, which sets the current transfer coefficient of the model

The device can be used to study the behavior of electronic circuits under the influence of various destabilizing factors. Due to the increased accuracy of modeling the input and output characteristics and the possibility of changing the current transfer ratio without changing these characteristics, the nomenclature of the studied radio electronic circuits has been expanded, it is possible to investigate nonlinear circuits.

Claims (2)

1. A device for simulating a semiconductor element, comprising a voltage generator and a current generator, characterized in that, in order to improve the modeling accuracy, operational amplifiers, a voltage divider and transistors are introduced into it, the base of which is connected to non-inverting inputs of operational amplifiers, the first of which is captured by a single feedback, in the feedback of the second operational amplifier, a voltage divider, the base of the shuzy transistor is connected to the inverting input of the operating force bodies, the outputs of the operational amplifiers are connected to the corresponding inputs of the current generator, the output of which is connected via a voltage generator to the collectors of the transistors, whose emitters are combined. 2. The device according to claim 1, differs from the fact that the current generator is made on a transistor, to the base of which the output of the voltage-current converter is connected. Sources of information taken into account in the examination: 1. USSR author's certificate N827O353, Kn. G 06 Q 7/62, 1968. 2. Stepanenko MP Fundamentals of the Theory of Transistors and Transistor Circuits. M., Energie, 1973, p. 2O9-214.