SU698011A1 - Function converter - Google Patents

Description

(54) FUNCTIONAL CONVERTER

This invention relates to the field of analog-digital computing. A known functional converter containing a comparison unit, the first input of which is connected to the converter input and the second to the output of the reference voltage generating unit, the output of the comparison unit is connected to the input of the control unit, the output of which is connected to the inputs of the generating unit and the voltage setting unit. The disadvantage of this functional converter is that it only reproduces the class of functions that generates the voltage setting block. It should be noted that the block for setting voltages generates time functions, not functions of the input argument. This leads to a restriction on the class of reproducible functions. The closest technical solution to this invention is a functional converter 2, containing two links, each of which is implemented on a nonlinear element and an adder, connected by an output to the input of a nonlinear element. the output adder, whose output is the output of the converter, the outputs of the adders of each of the links are connected to the inputs of the output adder, the outputs of the nonlinear blocks are connected to the inputs of the output adder and the first inputs of the adders of each of the links, the second inputs of the adders of each of the links are combined and are the input of -. educator The disadvantages of such a converter are the limited functionality that prevents the reproduction of discontinuous functions, and the impossibility of automating the adjustment of the converter from one reproduced function to another. The aim of the invention is to expand the class of reproducible fundamental transducers by reproducing discontinuous functions. This is achieved by the fact that a functional converter containing a non-linear element, the first adder, the output of which is connected to the input of the non-linear element, the second adder, the output of which is the output

functional converter, additionally contains four digitally controlled resistances, a comparator, a controlled reference voltage source, a memory unit and a switching unit, the outputs of which are connected to the control inputs of the digital resistance controllers and a controlled reference voltage source, and information inputs; - with the outputs of the memory block, the output of the controlled voltage source is connected to

the first input of the comparator, the second input of which is the input of the functional converter, and the output is connected to the control inputs of the memory unit and the switching unit, the first and second inputs of the first adder are connected via the first and second digitally controlled counters to the second input of the comparator and to the nonlinear output element, the first and second inputs of the second adder through the third and fourth digital-controlled resistances are connected respectively with the output of the first adder and the output of the non-, linear element.

The block diagram of the proposed Converter shown in the drawing.

The transducer contains the first, second, third, and fourth digitally controlled impedances 1, 2, 3, and 4, the first and second adders 5 and 6, and the nonlinear element.

7, controlled voltage reference

8, comparator 9, memory block 10, comm.

Functional Converter works as follows.

The reproducible function is divided into approximation areas based on the required

approximation accuracy, type of nonlinear characteristics (Element 7 and converter functionality). At each piece of piecewise nonlinear approximation carried out by the converter, the values of the digitally controlled resistances 1, 2, 3, 4, provide the best approximation of the reproduced function, and the value of the reference input voltage

comparator 9 to determine the start of the next approximation. The codes of these quantities are recorded in the memory unit 10, forming the program of operation of the functional converter.

A feature of the operation of the proposed functional converter is that the switching of the approximation areas occurs with an increase in the input signal. Before applying the input signal to the converter, it is necessary to set the voltage corresponding to the end of the first one at the output of the controlled source of the reference voltage 8.

four

approximation area, and the values of the digitally controlled resistances 1, 2, 3, 4 must correspond to the first approximation area. When the input signal reaches the trigger threshold of the comparator 9, it generates a control signal that calls from memory unit 10 a set of parameters of the second approximation area, which through the AND switching unit is fed to the digitally controlled resistances 1, 2, 3, 4 and to the control source of the reference voltage wives 8.

The comparator 9 returns to the initial position. A further increase in the input signal leads to the triggering of the comparator at the input and voltage corresponding to the end of the second approximation area, and to a change in the parameters of the second approximation area by the parameters of the third.

Thus, a piecewise non-linear approximation of the function is performed.

Since, in the proposed converter, its program of work is pre-recorded in memory block 10, the setting for reproducing a given function can be automated using digital computer technology. This allows to significantly improve the technical and economic characteristics of the converter in comparison with the prototype.

The proposed functional converter allows reproducing discontinuous functions, if the boundaries of the approximation sections are removed at the points of discontinuity of the function, which expands its functionality in comparison with the prototype.

Claims (2)

1. Author's certificate of the USSR M 423138, cl. G 06 G 7/26, 1974. 2. Authors certificate of the USSR N 447724, cl. G 06 G 7/26, 1974 (prototype). eight