SU815652A1 - Digital voltmeter - Google Patents

Description

(54) DIGITAL VOLTMETER

I

The invention relates to a measurement technique and can be used in measuring voltage from man-power over time.

A digital voltmeter is known, made with compensatory autocorrelation. The measured voltage in it is connected via a switch to a voltage-code converter (PNK), a measurement is taken, stored in the memory of the computing device, and supplied to the code-voltage converter (PKN). From the output of the PCN, the voltage is again applied to the input of the NCP and the re-conversion is performed. The difference between the codes obtained in the first and second cycles is determined.

Further, the code corresponding to the value of Ic is summed with the difference obtained (the result of the first approximation). The whole process is then repeated, and the results of approximation are obtained in a similar way.

A disadvantage of the known device is low speed.

The closest technical solution to the proposed one is a digital voltmeter, the input of which through a null organ is connected to one

trigger input and delay line inputs. The second trigger input is connected to the output of the first null organ, one of the inputs of which is connected to the output of the sawtooth generator, the input of which is through the driver, the delay line and the diode connected to the output of the second trigger, the second output of which is connected to the diode array and the first key. The output of the first trigger is connected to one input of the second key, the output of which is connected to the account register, and the second input of the key is connected to the generator

pulses. Third key output

connected to the auxiliary register, the outputs of which are connected to the inputs of the matrix, the outputs of which are connected to one of the inputs of the keys, and on

other inputs are connected to the outputs of a source of exemplary voltages. The outputs of the keys from the fourth to the eleventh are connected and connected to the second zero Organ

in the first cycle of the voltmeter operation, the input voltage is converted and the result is entered into the count register. At the same time, information is entered into the auxiliary register (corresponding to three CTajMiaiM bits).

In the second cycle, depending on cocTOStmH of the auxiliary register, a certain horizontal bus is excited in the matrix. The input key is locked and one of the keys is opened, which connects the corresponding model, voltage to the INC. To the contents of the counting register is added the average code value in one of the eight intervals, in which is located the U obtained in the first cycle.

Then, the selected exemplary voltage is coded and the resulting code is subtracted from the contents of the account register .2.

A disadvantage of the known device is low speed.

The purpose of the invention is to increase the speed of a digital voltmeter.

The goal is achieved by the fact that a voltmeter containing a source of exemplary voltages, a coding unit, a linearly varying voltage generator is connected to the first inputs of the first and second measuring comparators, the second input of the first comparator is connected to the input terminal, the second input of the second comparator is common bus voltmeter, the output of the first comparator is connected to the input of the first trigger, the output of the second comparator - to the input, the second trigger, the outputs of the flip-flops are connected respectively to the two inputs of the joint element Adeni, the third input of which is connected to a pulse generator, an output with a counting input of a counter, correcting comparators, drivers and additional matching elements are inputted, with the outputs of the reference voltage source being connected to the first inputs of corrective comparators, the second inputs of which are connected to the output of a linearly variable generator voltage, and the outputs through the drivers are connected to the inputs of the coding matrix connected to the installation inputs of the counter through the first inputs of additional elements falls, the second entrances of which; c are connected to the output of the first trigger.

. The drawing shows a block diagram of a digital voltmeter.

The circuit contains source 1 of reference voltage, correction comparators 2, drivers 3, encoding matrix 4, sawtooth voltage generator 5, measuring comparators 6, 7, triggers 8 and 9, coincidence element 10, pulse generator 11, additional coincidence elements 12 and a counter 13

The device works in the following way. .

Pulse Reset (c) triggers 8 and 9 and counter 13 are set to the well, the left state.

With the arrival of a pulse, the sawtooth voltage generator 5 begins to form a linearly varying voltage and when compared with a zero potential, the comparator 7 is triggered, the trigger 9 is set to one and the counting pulses of the reference frequency received by the counter through the coincidence element 10 begin. The linearly varying voltage also goes to the corrective comparators 2. When comparing the instantaneous values of the linearly varying voltage with the reference voltages, the comparators 2 form voltage drops that are formed by the formers 3 and through the coding matrix 4, the open elements of the match 12 establish in the counter, numbers corresponding to the values of the reference voltages. When comparing the linearly varying voltage with

5 and the comparator b is triggered, the trigger 8 is set to one, the counting of pulses in the counter 13 stops.

At the moments of correction, the error due to nonlinearity and steepness of the transformation is absent.

The proposed device has a high speed, since measurement and correction is carried out

 in one cycle.

Claims (2)

1. Gelman, M.M., et al. Automatic correction of systematic errors in transducers and reference code. M. Energie, 1974, with. 69 2. Authors certificate USSR 147107, cl. H 03 K 13/20, 1960.