Digital converter device and method for converting an analog signal into a digital signal

摘要

A direct conversion of an analog signal having a low signal level into a corresponding binary digital signal is achieved by a device which comprises a clock generator for generating a current of pulses and a pair of gates which optionally conduct the pulses via one of two current paths in dependence on a predetermined difference between the analog signal and a control signal. A counter chain provides an up/down counting of the pulses conducted via associated current paths and generates a binary digital output signal corresponding to the analog signal. A pair of digital/analog converters converts the digital output signal into a continuous step-shaped signal which is compared with the analog signal in a voltage comparator and amplifier. A differential signal is generated for a difference between analog and control signals and applied to the gates in order to determine the selection of the current paths and to enable the counter chain to track the analog signal.