An analog-to-digital converter (ADC) has been disclosed. In some implementations, the ADC is configured to generate ADC samples based on input signals and an ADC input clock. The ADC is further configured to generate at a first time point a synchronized start signal indicating a starting point of capturing the ADC samples. The start signal and a system clock can be synchronized at a second time point. At a third time point, a capturing sample clock for capturing the ADC samples is generated. The synchronized start signal and the capturing sample clock can be input to a counter to determine a time difference between the second and third time points. An ADC output timing of the ADC samples can be determined based on the time difference.