P‐37: A High Accuracy Current Comparison Scheme for External Compensation Circuit of AMOLED Displays

A current comparison scheme for external compensation circuit of AMOLED displays is proposed. In this scheme, a current comparator is designed to sense the difference between the reference current and the driving current of pixels and to output a corresponding digital signal to the compensation block. For the current comparator, a sense amplifier is used to amplify the current difference, which can effectively increase the accuracy of the current comparator. Simulation results show that the accuracy of the proposed current comparator is 1nA and the sensing error is lower than 0.224 %, when the reference current is 500 nA.