Fast voltage‐driving scheme for AMOLED displays based on internal feedback

— A new driving scheme for active-matrix organic light-emitting diodes (AMOLED) displays based on voltage programming is proposed. While conventional voltage drivers have a trade-off between speed and accuracy, the new scheme is inherently fast and accurate. Based on the new driving scheme, a fast pixel circuit is designed using amorphous-silicon (a-Si) thin-film transistors (TFTs). As the simulation results indicate, this pixel circuit can compensate the threshold-voltage shift (VT shift) of the driver transistors. This pixel can be programmed in just 10 μsec, and it can compensate the threshold-voltage shifts over 5 V with an error rate of less than 5% for a 1 -μA pixel current.

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