ADAPTIVE CONVERTER OF ANALOG-SIGNALS

An analog-to-digital converter using the principle of delta-modulation is proposed, The ADC contains an additional adaptive circuit controll ing the quantization step depending on the rate of the input signal va riation. This solution allows the dynamic range of the ADC to be signi ficantly extended without markedly increasing the discretization frequ ency and without any loss in the maximum resolution at the points of s ignal extreme. The ADC is intended for converting analog geophysical s ignals in the 0-200 Hz frequency interval. The dynamic range of the co nverter is 72 dB; power consumption, 250 mW; harmonic distortions at 1 25 Hz do not exceed 0.05% in the 20 dB range.