SU1457156A1 - Double-threshold comparator - Google Patents

Abstract

The invention relates to a pulse technique and is intended to create a jump in the output signal when the input voltage reaches a certain value. The purpose of the invention is to increase the stability of the discrimination zone. For this purpose, a two-pole current stabilizer 8 and a pulse generator 9 are introduced into the comparator. When analyzing two signals arriving at the input buses 4 and 5, a useful signal appears in the output of the comparator in the form of a pulse sequence if the difference between the amplitudes of these signals satisfies the Limax- and mts condition, where and D & i & o are the boundaries of the discrimination zone, established with the help of resistors 6 and 7 and stabilized by the current generator 8. 2 Il. (Oh (L

Description

Fib.1

The invention relates to a pulse technique and is intended to generate an output signal abruptly when the input voltage reaches a certain value.

The purpose of the invention is to increase the stability of the zone of discrimination,

Figure 1 presents the functional diagram of the comparator; Fig. 2 shows diagrams of stresses that explain his work,

The two-threshold comparator contains a block of unequalities, the first and second inputs of which are connected to the outputs of the first and second comparison elements 2 and 3, the direct inputs of which are interconnected and are the first input 4 of the device, the second input 5 of which is the first output the first resistor 6, connected by its second output to the inverted input of the first comparison element 2, is connected to the same input a second resistor 7 connected to the inverted input of the second comparison element 3 to which through a two-pole stabilizer 8 current connected to the generator 9 two-pole pulses

The comparator works as follows.

With equal input voltages

and

6U,

and and

8X2

On buses 4 and 5 at the inverted inputs of comparators 2 and 3, they are, with voltage, derived from the flow of current from the output of the current stabilizer unit 8 through resistors 6 and 7 and the input bus 5 to the source and gx. With a positive current direction from the device 8 at the outputs of the comparator, the voltage is zero or negative (depending on the type of comparator used). At the output of the inequality element 1, the voltage is zero.

With a negative current from source 9 at the outputs of Comparators 2 and 3, positive polarity voltage occurs, and at the output of voltage element 1 is absent.

The resistance value of the resistor 6 is chosen so that the drop in the voltage in it corresponds to the first trigger threshold of the comparator, after which the resistance value 7 is selected so that the drop in the resistor 6 or 7 is equal to the specified second threshold threshold. Resistors 6 and 7 can be used for dl variables. easy adjustment of the thresholds of the comparator.

Let us assume that the voltage across the bus 5 Uj is larger than the voltage across the 4 Tlgx i bus, but the difference between these voltages is less than the first comparator threshold, t, e is less than the voltage of the resistor .6, and they are positive polarity. In this case, when the current direction is negative, device B has negative voltages at the inputs of comparators 2 and 3, the output voltages from the comparators are positive polarity, and there is no voltage from the output of element 1.

With a positive direction of current from the output of unit 8, the inverting inputs of the comparators have positive voltages, the outputs of the voltage are negative, and there is no voltage from the output of element 1.

If the voltage difference between buses 4 and 5 is more than the first threshold of the comparator, but less than the second threshold of the comparator, then during the time when this difference has the same sign as the voltage from the output of block 8, the output voltage is zero, In another period of operation of block 8, the voltage on the sign will be opposite to the voltage on the inverse input of the comparator 2 and therefore a positive polarity pulse will be generated from the output of element 1 and the output.

Thus, if the voltage imbalance between buses 4 and 5 is more than the first pickup threshold, but less than the second pickup threshold, a continuous sequence of pulses is generated on the output spr indicating the presence of voltage difference modulo U5X, and Lg over the first comparator pickup threshold, but less than the second trigger threshold of the comparator.

If the voltage difference between buses 4 and 5 is more than the second response threshold, then from the outputs of Comparators 2 and 3, the voltages are always the same polarity and there is no voltage at the output.

Claims (1)

Claims of the invention A two-threshold comparator containing an inequality block, to the first and second inputs of which are connected the outputs of the first and second comparison elements, the direct inputs of which are interconnected and are the first input of the device, the second input of which is the first output of the first resistor, connected by its second output to the inverse input Editor A. Motyl Phases. 2 Compiled by E.Mirkin Tehred M. Didyk the first element of the comparison, to the same input the first output is connected to the second resistor connected to the inverse input of the second element of the comparison, characterized in that in order to increase the stability of the area of the direction of rotation, a two-pole current regulator and a pulse generator connected in series and connected to the inverse of the second element of the comparison. (8h.g GKorrektor V. But ha