SU1026117A1 - Device for measuring time intervals - Google Patents

Abstract

A DEVICE FOR MEASURING TIME INTERVALS, containing three elements and, the first input of the first of which is connected to the input of the device, and the output is connected to the first input of the OR element, the output of which is connected to the input of the first of two elements; , comrade, the output of the second element -. This AND is connected to the input of the high-order counter, the output (э of the third EESES - –G A - 1 3i: -; /,:, /,,::; .., I; - I;,.;}, l; - ., t S ti S l: tXCfKKntM 2l ment And is connected to the input of the low-order counter and to the second input of the NL, exc, and tsu with the fact that, in order to simplify the device, it is entered; three elements NOT, the input of the first element is NOT connected to the input of the device and the first input of the second element AND, the output of the first delay element is connected directly to the second input of the second AND element and to the rtepBOMy input of the third AND element and through the second element t delay to the second input of the third element Nick the input of the second element NOT, the output of which is connected to / T1 with the third input of the second element I, the output of which is the third element ij is NOT connected to the second input (F of the first element AND the output of the first element is NOT connected to the third with the input of the third element I. to f

Description

The invention relates to a measurement technique and is intended to measure time intervals and a pulse repetition period.

A device for measuring a period is known, comprising a form TSTSa, a counter, a counting unit, a trigger, a generator, a selector, OR elements,.

A disadvantage of the known device is its complexity and the impossibility of using it for measuring time intervals of the nanosecond range.

The closest in technical essence to the present invention is a device for measuring time intervals containing an OR element, four AND elements, three delay elements, two flip-flops, an OR-H element a high-order counter, a low-order counter 2j.

The disadvantage of this device is its complexity, since two triggers, three delay elements, are used.

 The purpose of the invention is to simplify the device.

This goal is achieved by the fact that a device for measuring time intervals, containing three elements AND, the first input of which is connected to the input of the device and the output connected to the first input. the house of the OR element, whose output is connected to the input of the first of the two delay elements, the output of the second element AND is connected to the input of the high-order counter, the output of the third element AND is connected to the input of the lower-order counter and the second input of the I1B1 element, are entered and the input of the first element is NOT connected to the input of the device and the first input of the second element AND, the output of the first delay element is connected directly to the second input of the second element AND and to the first input of the third element None through the second delay element and to the second input of the third element AND to the input of the second element NOT, the output of which is connected to the third input of the second element AND, the output of which through the third element is NOT connected to the second input of the First element AND, the output of the first element is NOT connected to the Third the input of the third element and.

Figure 1 shows the block diagram of the device; figure 2 - timing charts of his work. ,

The device contains an element OR three elements 2-4, two elements 5 and 6 delays, a counter 7 higher bits, a counter 8 lower bits up to three elements NOT 9-11.

The device works as follows.

The measured pulse signal with a duration equal to the time ff (Fig. 2, a) is fed to the first input of the elements 2 and 3 and through the element NOT 9 prohibits the passage of the signal through the element 4 (fig 2) time t (tf to the counter 8 least significant bits. Since from element 5 the delay to the second input of element I 3 is supplied in the initial state, the level O, and to the third input from the element NOT 10

then from the output element

level

FROM (FIG. 2B) the level O inverted by the element NOT 11 permits the passage of the measured pulse signal through the element 2 (fig.2b) and the element OR 1 to the delay element 5, which delays it by time t - t (Fig.2g) . From the output of the delay element 5, the pulses are fed to the second input of the And 3 elements and to the first - the And 4 element, in addition, the delays delayed by the 6 element for the time -t -t (fig. 2d) are delivered from the third input of the 4th element and through the element NOT 10 is at the second input of the element AND 3, since at time i} of Fig. 2a, d, g at all the inputs of the element And 3 is level 1, then at the output of this element a pulse of duration equal to the time (Fig. 3) is formed, which, through element 11, prohibits the passage of the measured signal at this point in time (fig. 2b), likewise n oiskhodit division of the measured pulse signal at t-j-t to time until the device is present at the input level 1. When this counter 7 pack Pih records the number of bits of whole divisions. As soon as the device enters the Vits level O, i.e. if the measured pulse terminates, then the impulse is prohibited to pass through the AND 3 element and the pulses through the AND 4 element to the counter 8 least significant bits are allowed to pass. Moreover, a pulse of duration equal to time (fig. 2b), which is the remainder of the division, from the output of the delay element 5 is fed to the input of the element I4 directly, and to the other input-through the delayed element b, thus, to the inputs of the element: I4 two .pulse synals shifted relative to each other by the time i -tj (Fig. 2d, d). At the output of element I4, a pulse signal is generated, the duration of which is shorter than the duration of the original signal at the time (Fig. 2g), which is detected by the low-order counter 8 and through the element OR 1 is fed again to the input of the delay element 5. Further, the circulation process in a closed circuit (delay elements 5 and 6) of the AND 4 and OR 1 elements will occur similarly to the first circulation cycle and stop when the pulse duration becomes less than the element delay time b (Fig. 2, time

The duration of the measured interval is equal to

t5-t, N trtiVNi (4-ti), where H is the kodg recorded in the high-order counter and corresponding to the whole number of cases, /

N is the code recorded in the low-order counter and corresponding to the total number of reference cycles.

The introduction of three elements did NOT allow us to simplify the proposed device, since we excluded the two triggers, the delay element, the element OR NOT, the element AND, while retaining all its characteristics.

f 4V

FIG.

Claims (1)

DEVICE FOR MEASURING TIME INTERVALS, containing three AND elements, the first input of the first of which is connected to the input of the device, and the output is connected to the first input of the OR element, the output of which is connected to the input of the first of the two delay elements, the output of the second AND element is connected to low-order counter input and with a second input. element OR, on the basis of the fact that, in order to simplify the device; three elements are NOT inserted into it, and the input of the first element is NOT connected to the input of the device and the first input of the second element And, the output of the first delay element is connected directly to the second input of the second element And to the first input of the third element And through the second delay element to the second input of the third AND element and to the input of the second element NOT, the output of which is connected to the third input of the second And element, the output of which is through the third ele- ment; the moment is NOT connected to the second input of the first element AND> the output of the first one And is connected to the input of the old- counter ^{: the} element is NOT connected to the third digit, the output of the third electronic input of the third 8 (About element I. Figure 1 1026117s