A correlation-based background calibration technology for the pipeline A/D Converter

This paper describes a correlation-based background calibration method to calibrate the linear and non-linear gain errors of pipelined ADCs. The calibration algorithm introduces a sequence PN to the input of the sub-ADC to have the output code modulated, estimates the errors by correlating the injected sequence with the output code, and calibrates the errors based on a LMS algorithm. Simulation results show that, with an equivalent gain error 2% and a 3-order nonlinear gain error 2%, after calibration, the measured DNL and INL were improved to −0.46/0.88 LSB and −0.81/0.92 LSB, respectively, and the SFDR/SNDR are improved to 93.8dB and78.6 dB, respectively.