A Memory-in-Pixel Circuit for Low-Power Liquid Crystal Displays With Low Temperature Poly-Silicon and Oxide Thin Film Transistors

Abstract

We propose a new memory-in-pixel (MIP) circuit using low temperature poly-silicon and oxide (LTPO) thin film transistors (TFTs) to achieve the high reliability as well as low power consumption. The proposed pixel circuit can greatly reduce the frame frequency due to extremely low leakage current of oxide TFTs. Moreover, the driving TFTs of the circuit can be stable under continuous stress for a long period of time because low temperature poly-silicon TFTs show high reliability. The pixel is driven directly by applying black or white voltage so that a flicker can be minimized. Fabricated circuit successfully verifies the circuit performance under the frame frequency of 1/60 Hz and the polarity inversion frequency of 0.5 Hz. Therefore, we expect that our proposed MIP circuit can provide flicker-free liquid crystal displays featuring low power consumption as well as high reliability.