High resolution floating-point analog-to-digital converter

Floating-Point Analog-to-Digital Converters (FPADC) are required for acquiring high dynamic signals. This paper presents an FP-ADC conceived to realize a higher acquisition rate, while preserving the accuracy of classical solutions. In the proposed circuit, two ADCs operates simultaneously, in parallel: one acquires the exponent, while the second one, with a variable gain, finds out the best representation of mantissa. If an incorrect gain was set, the conversion is repeated based on the last acquired exponent. It is shown in the present paper, both theoretically and by simulation, that this new FP-ADC exhibits superior statistical characteristics. The domain of the input signals that can be converted by the FP-ADC is several orders of magnitude higher than that of a fixed-point ADC. Compared to classic FP-ADCs, this new FP-ADC is characterized by a higher acquisition rate.