A novel pixel memory using integrated voltage-loss-compensation (VLC) circuit for ultra-low-power TFT-LCDs

— A novel pixel memory using an integrated voltage-loss-compensation (VLC) circuit has been proposed for ultra-low-power TFT-LCDs, which can increase the number of gray-scale levels for a single subpixel using an analog voltage gray-scale technique. The new pixel with a VLC circuit is integrated under a small reflective electrode in a high-transmissive aperture-ratio (39%) 3.17-in. HVGA transflective panel by using a standard low-temperature-polysilicon process based on 1.5-μm rules. No additional process steps are required. The VLC circuit in each pixel enables simultaneous refresh with a very small change in voltage, resulting in a two-orders-of-magnitude reduction in circuit power for a 64-color image display. The advanced transflective TFT-LCD using the newly proposed pixel can display high-quality multi-color images anytime and anywhere, due to its low power consumption and good outdoor readability.