Opportunistic multichannel driving scheme for low power mobile TFT-LCD driver IC

A novel source driving scheme called opportunistic multichannel driving (OMCD) is proposed for use in mobile TFT-LCD driver ICs (T-LDIs). In the OMCD scheme, the operation of the source drivers of a T-LDI is controlled by the equivalence of RGB colour data for adjacent pixels. That is, one source driver drives the neighbouring source lines as well as the corresponding one when the colour data of adjacent pixcels are identical to each other. With this scheme, all the source drivers associated with the neighbouring source lines can be completely turned off, allowing the reduction of static and dynamic current of these drivers. A test chip was fabricated in a 5 V/0.8 μm 2.5 V/0.25 μm triple-metal CMOS process, and the experimental result shows that the power reduction of 12-21% was obtained with die size overhead less than 0.5%.