Disclosed are systems employing a digital background calibration technique for linearizing the front-end circuits of IF-sampling ADCs. The disclosed systems and methods employ a power series model to eliminate the static non-linearity with split-ADC architecture and LMS algorithm for background learning. The present disclosure utilizes a technique for applying two different offset signals to the input of two conversion paths in the split-ADC architecture. When the system nonlinearity is successfully calibrated, the output difference between the two conversion paths results in a fixed offset that is identical to the offset injected at the input. The disclosed digital background calibration technique can linearize the front-end circuits of high-speed ADCs and significantly reduce power consumption.