Спосіб аналого-цифрового перетворення і пристрій для його реалізації

Abstract

A method of analogue-to-digital conversion and a device for implementation thereof relate to digital measuring technique and computation engineering and can be used for conversion of analog quantities to digital quanties. In a method of analog-to-digital transformation based on charge redistribution of capacitor matrix, a procedure of digital calibration is incorporated. The procedure includes following steps: real weights of high-order inexact digits is measured using low-order digits and stored in the main memory. Thereafter, during process of the main transformation, output code is formed using addition of corresponding digital equivalent of weight of digits using in transformation. To implement the method to the said device the main memory, a control unit, a switching element, a decoder, counters of calibration and addresses, multiplexer, a masking unit, an output register, a control signal bus, an output analogue bus, an output digital bus are incorporated. The main capacitor matrix comprises n capacitors, rated values of two adjacent capacitors are a times differ, where a - the base of the counting system are incorporated. Output of the address counter is connected to address inputs of the main and random RAM memory. Output of the main memory via the masking unit is connected to the addition unit which is together with the output register forms a storage unit. Output of the calibration counter is connected to the address counter and via the decoder is connected to stepwise approximation registers. Output of comparison circuit is connected to the main and supplementary stepwise approximation registers and to the masking unit. Outputs of the control unit is connected to corresponding inputs of both stepwise approximation registers, memory units, counters, the multiplexer and to the output register. The technical result is increase of operating speed of the converter due to avoiding time loss to shape correcting signals.