Analog Devices, Inc.
Analog-to-digital converter speed calibration techniques

Abstract:

A conversion time and an acquisition time of an ADC can be estimated so that a speed of the ADC can be calibrated. An ADC circuit can perform M bit-trials in its conversion phase and continue performing additional bit-trials in a calibration mode. The ADC can count the number of additional bit-trials performed, e.g., X bit-trials, that occur before the next conversion phase, where additional bit-trials can be considered to be the number of available bit-trials during an acquisition time if the ADC continues performing bit-trials instead of sampling an input signal. The ADC can estimate the conversion time and the acquisition time using M and X. Then, the conversion time of the ADC can be calibrated by adjusting one or more of the comparison time, DAC settling delay, and logic propagation delay.