THE METHODOLOGY OF CIRCUIT CONSTRUCTION OF THE ANALOG VALUE CONVERTER IN THE TIMEFRAME

Abstract

Background. Most modern digital voltmeters use an analog-to-digital converter (ADC) of the time-pulse type with two-stage integration, which takes place in two stages – integration and counting. During the counting, in accordance with the principle of operation of the converter, the input information is not received in the ADC and is lost. The aim is to develop a technique for converting an analog quantity into a discrete one without losing information the input signal. Materials and methods. An approach to the construction of an integrating converter of the measured voltage in a time and interval in which integration occurs during the entire time of the input signal conversion is presented. The novelty of the approach is to eliminate the waste of time on service signals for resetting (or zeroing) the voltage on the storage capacitor, due to the use of a controlled generator of linearly varying voltage on two op-amps, and the possibility of direct measurement of the bipolar input signal. Results. A technique for the circuit design of an analog magnitude converter in a time interval is proposed, which allows the conversion of a bipolar input signal without additional circuit elements. The following are presented: a schematic electrical diagram of the converter; a mathematical model of converting the input signal into a time interval; recommendations for obtaining a digital code at the output of the converter; a method of circuit design of the converter. Conclusions. The use of the considered technique makes it possible to integrate the input signal without losing time to perform transformations on service signals. The results can be used to build integrating ADCs for wide application in industrial devices and in other fields of science and technology.

Keywords

• analog-to-digital converter
• integrating adc
• linearly varying voltage generator
• voltage-time interval converter
• schmitt trigger