SU593310A1 - Voltage to code converter - Google Patents

Description

prohibition 7, elements 8 and 9, reversible counter 10, trigger li and reset element 12. Calibration unit 2 has reset element 12, four elements 13-16, two counters

17 and 18, the element is closed 19 and the element of discharge 20.

The device operates in two modes: calibration characteristics of the converter and measurement.

The calibration mode of the converter characteristic is performed by polling a channel whose input is grounded. In this case, the additive error of the converter is determined, and the pulses of the oscillator 3 of the reference frequency arrive through the element 13 at the counter 17 and are stored there until the next onros of this channel. The falling edge of the pulse converter 1 starts the generator of 6 auxiliary pulses.

The frequency of the generator 6 clock pulses is less than the pulse frequency of the generator 3 of the frequency support.

The pulses of the heater 6 are fed through the elements 7 and 8 into the reversible counter 10 via the subtraction bus. At the instant of the coincidence of the pulses, the generator 3 with the impulse of the operator 6 triggered a prohibition element 7, and the flow of the pulses of the generator A of the auxiliary signals to the reversible screw 10 is stopped.

The measurement mode starts from the moment the measured value U is connected to the input of the voltage converter 1 in the pulse duration. In this case, the pulses of the generator 3 are fed through an element AND 14 to the second counter 18 of the calibration block 2. At the time of the coincidence of the codes in the counters 17 and

18 works the element And 16, allowing the operation of the element And 14. Therefore, the following pulses of the generator 3 are fed to the converter 4 of the number of pulses in the code. The falling edge of the information pulse triggers the generator 6, the pulses of which through elements 7 and 8 are fed through the addition bus to the reversible counter 10. At the time when the pulses of the generator 3 coincide with the pulse of the generator 6, the prohibition element 7 is triggered and the generator 6 pulses stop flowing through the folding bar into the reversible counter 10. Trigger 11 speaks of adding (or subtracting) the code of the reversible counter 10 with the code of the converter 4 of the number of pulses into the code. If the number of pulses of the generator 6 that arrived on the addition bus is greater than the number of pulses received on the subtraction bus of the reversible counter 10, then the trigger 11 is triggered. In this case, the code of the reversible counter 10 folds together with the code of the converter 4. If the number of pulses of the generator 6, which arrived on the addition bus is less than the number of pulses received on the subtraction bus, trigger 11 does not work, and the reversing code

counter 10 is subtracted from converter code 4.

Next, follow the calibration mode of the converter characteristic and the measurement cycle.

Counters 10, 17, and 18 are reset by reset elements 12 and 20 to the zero position.

The accuracy of subtracting the additive error from the value of the measured value is equal to the difference between the pulse frequency of the oscillator 3 and the frequency generator and the generator 6 auxiliary signals. High conversion accuracy is achieved without using high frequency elements in the device.

Claims (2)

1.Smolov V. B. and others. Semiconductor, coding and decoding converters tension M., “Energie, 1967, p. 200 2. “Digital electrical measuring instruments. Ed. V.M. Shl Ndina. M., 1972, p. 931.