SU433410A1 - INTEGRATING ANALOG-DIGITAL! CONVERTER_. - Google Patents

Description

one

FIELD OF THE INVENTION The invention relates to digital-electrical engineering and can be applied to digital devices with zero offset.

Integrated analogue go-digital converters are known to have an offset zero and contain an integrator, a zero-organ, reference voltage sources, a frequency divider, coincidence circuits, and keys.

However, such converters are characterized by relatively low conversion accuracy, due to the fact that integration and conversion in them occurs from different sources of reference voltage and into different half-periods of the signal, which determines the conversion time and is adjusted to the frequency of the power supply.

The purpose of the invention is to improve the accuracy of the conversion.

This is achieved by the fact that the inputs of the two switches are connected to the terminals of the reference voltage source, the output and the control input of the first switch are connected respectively to the input of the integrator and de-; power supply frequency; the output 5 and the control input of the second key are connected respectively to the common; A wire and an output of the coincidence circuit, to the inputs of which are connected the zero-output outputs, the frequency divider and the power supply through the matching node.

FIG. I presents the scheme of the proposed converter; in: FIG. 2 - work diagram.

5The converter contains in-,

Tegrator I, source 2 of reference voltage, keys 3 and 4, as well as a null organ, a frequency divider and a coincidence circuit (in the drawing, not yet-i

0 entered). In doing so, key B is controlled; signals from the output of the frequency divider, and the key 4 - signals from the output of the coincidence circuit, to the input of which signals from the null organ, de,

5 | frequency generator from the AC power source. The converter works as follows. Using keys, one and the other KB of the reference voltage source is used for integration (the negative polarity of the source is connected to the integrator's input), then for the time-pulse conversion (the positive polarity of the source is connected to the integrator's input) voltage to the integrator eliminates the additive error arising from the mutual care of the voltage source voltage. In addition, in this case, as can be seen from figure 2g, the integrato p operates in integration mode for one period of the power source signal. In this case, if there is a zero input signal, the integration and the time-pulse conversion are used the same. the same period of the power source signal (firm 2b), which specifies the conversion time through the frequency divider (Fig. 2a). This allows you to eliminate the additive error due to the fact that the different control voltage periods are not the same during automatic frequency control. Subject of the Invention An integrating analog-to-digital converter comprising an integrator, a zero-organ, a reference voltage source, a frequency divider, coincidence circuits, and keys, characterized in that, in order to increase the conversion accuracy, the inputs of the two switches are connected to the poles of the voltage reference source, the output and control input of the first key are connected respectively to the input of the integrator and the power network clock; the output and control input of the second switch are connected respectively to the common wire and the output of the coincidence circuit, to the inputs of which the outputs of the null organ, frequency divider and via the matching node of the power source are connected.