SU1238249A1 - Device for checking and converting analog signals - Google Patents

Abstract

The invention relates to telecommunications. Control errors due to the effect of destabilizing interference are reduced. The device co - holds the generator (D) 1 clock pulses, D 2 rectangular pulses, a block of separation diodes, the main source (Is) 4 analog signals, an additional Is 5 analog signals, two blocks 6 and 7 of the comparison. The 8 nd reference signal, two single vibrators 9 and 10, the EXTRACT element OR 11, element 12 and the counter .13 pulses. The measurement of the component error of the device caused by the influence of external interference on Ec 4 reduces the total error of the control by HecKojibKO. In this case, the error is determined mainly only by the instability of Is 8 and the comparison unit and reaches an institute of about 0, 1-0,5%. The goal is achieved by introducing Is 5, block 7, one-shot 10, element II, block 3, D 2. 2 ill. g

Description

The invention relates to telecommunications and can be used in data transmission systems for control and testing of technical systems.

The purpose of the invention is to reduce control errors caused by the effect of destabilizing interference,

Figure 1 shows the electrical circuit diagram of a device for monitoring and converting analog signals; 2 shows timing diagrams for the operation of the device. . .

Device for control and pre10

capacitors. During the pause yT. & T between pulses the discharge of capacitors occurs through the corresponding resistors of sources 4 and, 5 (due to the large resistance of generator 2 during the pause) with constant time 7 and t, (RC). When decondensing of tors at the moments of intersection of SC, t5) by output signals. and (t) and the CB (t) (Fig. 2B, i) of a given reference signal U, (t), the corresponding comparison blocks 6 and 7 are triggered, which results in the output of blocks 6 and 7 of the U signals. (t )

the formation of analog signals contains 5 and U, (t) (Fig.2, 6), which cause the corresponding single vibrators 9 and 10 to operate (tip over) (signals Ug (t) and (t), fig.2h, j). (In the simplest case shown in Fig. 2 (device operation mode), it is a given level Ug of the signal Ug (t), i.e. Ug, Ug (t), in other cases under Ug (t) the reference signal is implied ahead of a predetermined shape that optimizes the operation of the device S in each particular case.

Duration C t i, s t t output pulses Ug (t). one-shot proportional posthog

25

thirty

1 clock pulse generator, 2 pulse generator pulse generator, 3. separation diode block, main source A of analog signals, additional source 5 of analog

 signals, the first 6 and second 7 blocks of comparison, the source 8 of the reference signal, the first 9 and second 10 single vibrators, the element EXCLUSIVE OR 11, the element AND 12, the counter 13 pulses.

The device works as follows.

A trigger signal Ug (t) is supplied to the trigger input of the generator 1 clock pulses, which is in the simplest case (when the parameters of clock pulses (t) and. (T) are fixed beforehand). voltages), and in a more complicated case, the parameters of the pulse rates and (t), Z (t) can adaptively change — by a code. that carries information about the operating mode of generator 1, i.e. about the parameters of clock pulses C (t), U (t), produced by the generator. The clock pulses and (t) are fed to the input of the And 12 element and are clock pulses / A t counted at the output of the device 13. .. The clock pulses (t) {Fig. 2a) are fed to the input of the generator 2 rectangular pulses U, j (t) (Fig.28) and determine the parameters of the latter (duration, and pause LT, D T). 50 Thus generated positive rectangular pulses U (t) through the separating diodes of the block 3 step on. main power inputs 4

this time G and T (t RC) of the corresponding source 4, 5 analog signals (resistive-capacitive sensor). Comparison of these pulses in duration is carried out by 35 elements of the EXCLUSIVE ISH 11, during which a pulse (t) is formed. (Fig.2i), proportional to the difference of the signals of the main source of 4 analog information signals

3

Y (t) - X (t) e., (T): and

40

About the process

, W:

45 j

additional source 5 analogue signals of information on external information; (BB), - (t) or the amount of WB

 those. impulse, proportional to --- 1. . , - „. nationally (with a negligibly small error) controlled process (parameter): x (). V (t) -5 e)).

or x (t) y {t) -: (t /. Thus, if, as an additional source, 5 a sensor is used that senses only the explosive (t) and does not

and an additional 5 sources of analog-5S perceiving the main control signals, made in the form of resistive-capacitive sensors, during T, -Tj. fully charged them

0

capacitors. During the pause yT. & T between pulses the discharge of capacitors occurs through the corresponding resistors of sources 4 and, 5 (due to the large resistance of generator 2 during the pause) with constant time 7 and t, (RC). When decondensing of tors at the moments of intersection of SC, t5) by output signals. and (t) and the CB (t) (Fig. 2B, i) of a given reference signal U, (t), the corresponding comparison blocks 6 and 7 are triggered, which results in the output of blocks 6 and 7 of the U signals. (t )

5 and U, (t) (Fig. 2, 6), which cause the corresponding single vibrators 9 and 10 to operate (tip over) (signals Ug (t) and (t), Fig. 2g, j). (In the simplest case shown in Fig. 2 (device operation mode), it is a given level Ug of the signal Ug (t), i.e. Ug, Ug (t), in other cases, under Ug (t) the reference signal is implied ahead of a predetermined shape that optimizes the operation of the device S in each particular case.

this time G and T (t RC) of the corresponding source 4, 5 analog signals (resistive-capacitive sensor). Comparison of these pulses in duration is carried out by the element EXCLUSIVE ISH 11, during which a pulse (t) is formed. (Fig.2i), proportional to the difference of the signals of the main source of 4 analog information signals

3

Y (t) - X (t) e., (T): and

About the process

, W:

50

45 j

additional source 5 analogue signals of information on external information; (BB), - (t) or the amount of WB

 those. impulse proportional to --- 1. . , - „. nationally (with a negligibly small error) controlled process (parameter): x (). V (t) -5 e)).

or x (t) y {t) -: (t /. Thus, if, as an additional source, 5 a sensor is used that senses only the explosive (t) and does not

5S perceiving the main controlled quantity x (t), then the duration of the difference signal at the output of the element EXCLUSIVE OR 11 is proportional to

pure signal x (t) with the adjusted error from the explosive.

 Generator 1, element 12, counter 13 perform further on this difference signal (fig.2i) conversion and interval duration — frequency of pulses. At that, element 12 of the output clock clock pulses U (t) on the output (fig.2k) generator 1 only at the time of its second input of the output difference signal of the EXCLUSIVE OR element 11, thus allowing the counter 13 to count the number of pulses N filling the interval t, N tn / A t. Thus, at the output of the counter 13 there is a p-bit code (N) j, the number of pulses N, proportional to the monitored parameter x (t) in the time interval Ta T + dT T, + 4 Tj, which is in.

In a few dozen cases, the chian case is the spacing interval for the process- (parameters) x (t), y (t), j- (t). At the same time, the sampling frequency of 1 is actually attainable on a modern element base.

G5 --.-. t

logs, which is enough for most practical applications of the device.

Compensation of the component of the monitoring device, caused by interference (.ВВ) on the source of 4 analog signals, thus reduced reduces the total control error by several times (depending on the nature, quantity and level of explosives and type of sensors). In this case, the total error of the device is determined mainly only by the instability of the source 8 of the reference signal and the comparator unit and can reach values of the order of 0.1-0.5% under severe operating conditions of use. An example of an analog signal source can serve as a mechanical strain gauge, the circuit of which includes an additional (parallel) capacitor, and a sensor that perceives, under operating conditions, both the monitored voltage of the test object x (t) and the destabilizing explosive: the object temperature is (t), the vibration of the object (t) and others (, 4, ...). So on this sensor act 38249

signal y, (t) x (t). (t).

j. An example of an additional source

An analog signal can be of the same mechanical strain gauge with a capacitor connected in parallel, placed next to the main shadow sensor attached to the object, but glued, for example, to an auxiliary plate from the same 10 Material as the object under test. associated with the object. At the same time, this compensating strain gauge does not perceive the mechanical stress of the object, but perceives only BB5 (t). The device provides highly stable compensation for the effect of the signal interference on the sensor, i.e. a kind of subtraction:

20 x (t) y (t) - (t)

.

Claims (1)

1. I t; fft} TI tftft) S fW / i g . “F) j (t).