SU915238A1 - Logic element, excluding false signal at the output - Google Patents

Description

The invention relates to a pulse technique and can be used in various devices of discrete automation.

Known logic element containing a transistor, a diode, a pulse transformer, resistors, a capacitor [1).

The disadvantage is the possibility of the appearance of a false logical signal at the output in case of failure of its constituent elements.

Also known is a logic element containing controlled generators with transformer output and rectifier. mills (2).

The disadvantage is its complexity.

The purpose of the invention is the strengthening of the logical element.

This goal is achieved by the fact that the logic element, eliminating a false logical signal at the output, contains controlled generators with transformer output, amplifier with transformer output, the first and second rectifiers, the outputs of which through the separation resistors are connected to the output of the device and the second controlled generators, the power supply of the second controlled generator is connected to the output of the third rectifier, the input of which is connected to the output of the amplifier; with a transformer With an open output whose input is to the output of the third controlled oscillator, the second and third controlled oscillators are controlled by signals of one polarity, the first generator is controlled by signals of the other polarity, the control inputs of the second and third controlled generators are connected to '* rum device inputs through the newly entered first and second dividing resistors, the first controlled oscillator control input che_ _n Res re - introduced by the third and fourth divider resistors connected to the first and second inputs of the device.

Figures 1 and 2 show schematic diagrams of options for constructing a logic element that eliminates a false logic signal at the output for use of controlled oscillators with opposite polarities of voltages

30 input signals.

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The logic element, which excludes a false logical signal at the output, contains controlled generators 1 3 with control respectively from the signals of one and the other polarity with a transformer output, amplifier 5 with transformer output, rectifiers 5 to 7 with corresponding diodes 8 10 and capacitors 11 - 13, separation resistors 14 and 15 at the outputs of the rectifiers 6 'θ and 7 and the newly introduced separation resistors 16 - 19, the first input 20, the second input 21 and the output 22 of the device.

The device eliminates the possibility of 15 false signals at the output, i.e. the possibility of switching the logical ¹ Ό "to the" 1 "and vice versa in the case of using the bipolar signals, for example, when the logical" 1 "corresponds to the negative voltage of the polarity –O, and the logical · '0' * voltage positive polarity. The damage in the device only leads to the output of a logic signal at the output (the appearance of ”zero, voltage level '·), which can be regarded as an emergency signal.

With the specified polarities of the input signals, the logical elements realize the logical functions AND-NOT and OR-NOT, respectively,

In the first case, the device works as follows

When a negative voltage is applied to the input 21, a generator 3 is excited, high-frequency oscillations appear at its output, which are then amplified by amplifier 4, converted into direct current signals -40 and rectifier 7, and fed to the supply circuit of the generator 2.

A feature of generator 3 is the high-frequency output transformer 45, on the secondary winding of which the variable components of the collector power supply source in the event of damage to the filter elements of the latter do not create any 50

significant level. With the same purpose, a resistor is included in the collector circuit of the output transistor of the generator.

Amplifier 4 is assembled according to a scheme that excludes arbitrary excitation.

Rectifier 7 contains a capacitor 13 with four terminals, which is necessary for Togo so that if any of its terminals break, the constant component at the output of ^{6υ of the} rectifier also ^disappears . Thus, the breakdown or breakage of a capacitor does not cause, as in the case of using a conventional capacitor, the passage of high-frequency components of signals 65

rectifying oscillations of the generator 3 to the collector circuit of the output transistor of the generator 2, and in case of the breakdown of the latter in the transformed form, and to the output of the logic element circuit.

The generator 2 is built according to the same scheme as the generator 1. The output of the rectifier 6 of its oscillations is connected to the output 22 of the logic element. Generator 2 is energized only if negative voltage occurs at the inputs 20 and 21 at the same time. Then at the output of the element a signal of positive polarity takes place.

Generator 1 is assembled on transistors of opposite polarity, compared with transistors of generators 2 and 3. Therefore, generator 1 is excited only if there is a positive voltage at its input. In the presence of at least one of the inputs 20 or 21 of a positive voltage, the output of the logic element has a voltage of negative polarity.

Breaking or short-circuiting the elements of generators 1 - 3 only leads to the breakdown of their high-frequency oscillations and, as a result, to the loss of signals at the output of the logic element. Open or short circuit of rectifier circuits 5-7 causes only the disappearance of a constant voltage at the output of the logic element circuit. Yo, none of the damage to the circuit leads to the transformation of the output signals of positive polarity into signals of negative polarity and vice versa (that is, it does not lead to the transformation of the logical ’1’ ’into ** b’ * and vice versa).

The considered circuit of a logic element can be transformed into a circuit of other logic elements as a result of minor changes. Indeed, the connection of rectifier diode 9 to generator output 2 is not the anode, but the cathode and at the same time the connection of rectifier diode 8 to the generator output 1 by anode, anode cathode, convert the scheme of the logical element NAND in the scheme of the logical element I.

The combination of the diodes, the inputs 20 and 21 of the logical element AND-NOT converts it into. logical element is NOT.

Replacing transistors in the circuits of generators 1-3 with transistors with inverse conductivity leads to the conversion of the NAND circuit into the OR logic circuit. If, in addition, to change the connection of the diodes 9 · rectifiers 5 and 6, then the logical element AND-NOT is converted into a logical element OR-NOT.

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Claims (1)

Claim Logic, excluding spurious logic output, containing controlled generators with transformer output, amplifier with transformer output, first and second rectifiers, the outputs of which are connected to the output of the device through separation resistors, and the inputs are connected to the outputs of the first and second controlled generators, input the power supply of the second controlled generator is connected to the output of the third rectifier, the input of which is connected to the output of the amplifier with a transformer output, whose input to the output of the third directs the generator, characterized in that, in order to simplify, second and third generators You are a manageable. controlled by signals of one polarity, the first generator controlled from signals of the other polarity, the control inputs of the second and third controlled oscillators . connected to the first and second inlets of the device through the newly entered the first and second separation resistors, the control input of the first controlled generator through again The third and fourth inserted resistors are connected to the first and second inputs of the device.