FULL SCALE CALIBRATION OF ANALOG-TO-DIGITAL CONVERSION

摘要

Methods and arrangements enable ADCs (105) to be calibrated from reference signals with unknown parameters and/or with amplitudes that exceed the dynamic range of the ADCs (105). A given analog reference signal s(t) is supplied to an ADC (105). The output x(k) of the ADC (105) is used by calibration logic (320) to estimate at least one paramater of the reference signal. A FIR filter (455) accepts as input the x(k) signals and outputs and estimate ((k)) as the sampled instances of thes(t) signal. A reconstruction table is created that approximates the analog input signal in the digital domain using the knowledge of the analog input signal waveform type. The actual ADC (105) outputs are compared to the values in the reconstruction table to produce a correction table (350) for calibration. In an alternative embodiment, calibration logic (320) interpolates the output (x(k)) of the ADC (105) to reconstruct clipped portion(s) of the input analog reference signal s(t) when the amplitude of the input analog reference signals s(t) exceeds the full swing of the ADC (105). The FIR filter can thereafter use the reconstructed signal from the interpolation.