ADC linearity testing method with single analog monitoring port

Abstract

We propose an ADC linearity testing method with a single analog monitoring port. This method enables direct measurement of code transitions without clocking and digital signal processing. We analyzed code transition measurement errors caused by additional monitoring circuits, and verified that the errors are less than 0.1LSB with simulations. We applied the proposed testing method to laser wafer trimming (LWT) for ADC linearity improvement, and achieved integral non-linearity (INL) 0.26LSB and differential non-linearity (DNL) 0.30LSB respectively.