Reducing Power Consumption of Active-Matrix Mini-LED Backlit LCDs by Driving Circuit

An active-matrix (AM) driving circuit using a low-temperature poly-silicon thin-film transistor (LTPS TFT) is developed to reduce the power consumptionofmini-lightemitting diode (LED) backlit liquid-crystal displays (LCDs). By lowering the drain-source voltage (VDS) of the switching TFT on the driving current path, the range of required voltage across the proposed circuit can be reduced, decreasing the power consumption of the mini-LED backlight. The proposed circuit also can compensate for VTH variation in the LTPS TFT and the I-R rise of VSS to provide a uniform driving current to flow through the mini-LED. By measuring the I-V curves of a fabricated LTPS TFT, we build a reliable simulation model and compare the proposed circuit to that of the state-of-the-art. Simulated results indicate that the proposed circuit can improve the power consumption by 16.67% and reduce the current error rates below 8% when theVTH of TFT variesby±0.3 V andVSS rises+1 V.Measured results further confirm that the VDS of the switching TFT is reduced by 2.208 V compared to a 6T2C compensating circuit. Therefore, widespread applications of the proposed circuit for AM mini-LED backlit LCDs to produce highdynamic-range images are foreseeable.