Reducing Power Consumption of AM Mini-LED Displays Using TFT-Matching Pixel Circuit

This article presents a pixel circuit that is based on low-temperature polycrystalline silicon (LTPS) thin-film-transistors (TFTs) to reduce the power consumption of active-matrix (AM) mini-LED (light-emitting diode) displays. Using the TFT-matching compensation, the proposed circuit can reduce the total voltage across each pixel in the array, reducing the power consumption of the display. Compensating for the threshold voltage variation of LTPS TFTs and the current-resistance drop of VDD enables a stable driving current to be generated by the proposed circuit. To prove the reduction in power consumption, the proposed circuit and other compensating pixel circuits are compared. Simulations indicate that the power consumption of the proposed circuit is 13% lower than that of circuits with several TFTs in the driving current path. A 5.23-inch AM mini-LED display with a resolution of 160 × 135 and a frame rate of 120 Hz is implemented using the proposed circuit. Measurements demonstrate that the fabricated display produces uniform images at a gray level of 255. For the white image with a brightness of 1620 cd/m2, the power consumption of the display is 7.18 W.