SU535574A1 - Device for checking pulse counters - Google Patents

Description

one

The invention relates to a pulse technique.

A device for checking pulse counters is known, comprising a signal sensor, an amplifier, a threshold circuit, a mono-controlled trigger, a multivibrator, a control trigger, logic gates AND, an interval counter, OR elements, a short pulse counter, a strobe generator, a decoding unit, a loop detection trigger, memory register and read indicator.

The disadvantage of such a device is great complexity.

It is also known a device for testing pulse counters, consisting of a control counter, a code comparison circuit, a logical indicator block.

A disadvantage of this device is the need to use a control counter similar to the one being checked, and the control counter must be faster than checking one.

The closest to the technical essence of this invention is a device for checking pulse counters, containing an generator of an external start pulse train, the output of which is connected to the input of the checked counter, a multi-input comparison element, the inputs of which are connected to the outputs of the higher bits

the counter and the outputs of the control counter, the input of which is connected to the input of the generator of the pulse train with external start, the logic unit whose output is connected to the indicator, and the input is connected through the AND element to the output of the multi-input comparison element.

The disadvantage of such a device is the comparatively low measurement accuracy. The purpose of the invention is to improve the accuracy

measurements.

This is achieved due to the fact that a one-shot is added to the device, an additional multi-input comparison element and a delay element, and the inputs of the additional multi-input comparison element are connected to the low-order outputs of the counter being checked, the output of the additional multi-input comparison element is connected the input of which is connected through a delay element to the input of the generator of a pulse train with external start, and between the output of the logic element And and the input of the pulse generator with external start

one-shot is included.

The drawing shows a structural electrical circuit of the device.

The device contains a one-shot 1, the generator 2 packs of pulses with an external start,

control counter 3, delay element 4,

multiple input elements of comparison 5, 6, element 7, logical block 8, indicator 9.

The device works as follows.

After the control 3 and the tested 10 counters are installed in the “O” and the subsequent one-shot of the one-shot 1 using an external trigger (not shown), when the switch-off 1 is triggered, a 2-pulse pulse is sent to the generator input 2 of a given number of pulses. is a sequence of a given number of pulses that arrive at the input of the checked counter 10. The number of pulses in a packet at the output of the generator 2 must be equal to the coefficient of recalculation of those younger bits of the checked with etchika 10 which are connected to the inputs of comparing member 5.

In the case of a binary counter, this number is chosen from the condition, where k is the number of the indicated least significant bits. Consequently, with the correct operation of the counter 10, after recalculating the burst of pulses from the generator 2, the indicated lower bits of the counter 10 are set to the zero state, and the youngest of the senior bits groups of this counter to the unit state.

The pulse from the output of the one-shot 1 is also fed to the input of the control counter 3, therefore the first low-order bit of this counter is set to one. Comparison element 6 provides verification of the operation of the higher bits of the checked counter 10 by comparison with the operation of the control counter 3. If the codes in counter 3 and the higher bits of counter 10 match, and the code of the lower bits of counter 10 is zero, then the outputs of the elements of the comparison 5, 6, signals appear, and element 7 permits the delayed delay element 4 to pass a pulse from the output of the one-shot 1 to restart it.

The delay determined by the element of the delay 4 is chosen from the condition), where tn is the period of the pulses from the generator 2, and mouth is the total time of the establishment of the counters 3, 10 and the elements of the comparison 5.6. Thus, a multiple check of the counter 10 is automatically carried out.

If counter 10 is faulty (incorrectly counts the pulses, an incorrect reset to the bullets, etc.), then element 7 does not allow the pulse to start the one-shot 1, while logic unit 8 sends a "bad signal to the indicator, and the pulse count stops.

Claims (1)

Invention Formula A device for checking pulse counters containing an external start pulse generator, the output of which is connected to the input of the checked counter, a multi-input comparison element, whose inputs are connected to the high-level outputs of the checked counter and the outputs of the control counter whose input is connected to the input of the generator of the pack pulses with external By starting, the logic unit, the output of which is connected to the indicator, and the input is connected via a logic element AND to the output of the multi-input comparison element, characterized in that, in order to improve the measurement accuracy, a one-shot is added to it, an additional multi-input comparison element and a delay element, and of the multi-input comparison element is connected to the outputs of the lower bits of the tested -meter, the output of the additional input input comparison element is connected to the input of the logic element AND, the complementary input of which is connected via a delay element to the input of the pack generator pulses with an external start, and between the output of the logical element And the input of the generator of a pack of pulses with an external start included one-shot. External, launch