Active Matrix Micro-LED Display Control Techniques

Chip structure for high density and brightness micro LED displays that reduces the need for external driver ICs. The chip integrates the LED elements, MOSFETs, and connections on a package substrate. It has an input voltage pad, a main control circuit, and a source drive circuit. The main control circuit drives the MOSFETs which in turn source-drive the LEDs. This allows high density and brightness micro LED displays without needing external driver ICs, as the MOSFETs are integrated on the chip.

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MicroLED display panel and pixel driving circuit to improve efficiency, brightness, and gray levels. The driving circuit has a switch, driving unit, and selection unit. The switch controls data based on scan. The driving unit connects to the light-emitting microLEDs and first voltage. The selection unit connects to microLEDs, second voltage, and receives selection signal. Brightness and number of microLEDs lit are controlled by selection and driving based on selection/data. This allows partial microLED strings to be lit instead of all, improving efficiency. By selectively driving subsets, it increases brightness and enables more grayscales compared to driving full strings.

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Common-anode microLED display devices with improved efficiency and smaller driver size compared to conventional common-cathode designs. The common-anode microLEDs are driven by positive voltages from regulators instead of negative voltages. This avoids complex negative supply circuits and allows using smaller, less power-hungry n-channel transistors for the current drivers. The microLED arrays are bonded with metal-to-metal contacts to the backplane circuits, simplifying alignment. The common anode is deposited after etching the mesa structures. This allows precise alignment and bonding of the anode pads on the microLEDs to the backplane driver pads.

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Pixel design for displays with reduced power consumption and improved image quality in randomly aligned light-emitting element arrays. The pixel has two electrodes connected to light-emitting elements and two pixel circuits. One circuit is connected to a power source and generates the driving current based on scan and data signals. The other circuit is connected to a second power source. Electrical connections between the circuits and electrodes are selectively controlled based on signals. This allows opposite power sources for electrodes based on the alignment ratio of the elements. Reduces voltage difference and power consumption.

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Reducing pixel pitch of microLED displays by separating the microLED array from the drivers to allow closer packing of the microLEDs. The microLEDs are on one side of a substrate and the drivers are on the other side. Conductive paths in the substrate connect the microLEDs to the drivers. This allows smaller pixel sizes compared to having the drivers on the same side as the microLEDs. A separate data driver provides scan and PWM signals to the matrix drivers.

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MicroLED display pixel driver circuit that converts low-frequency input pulses into pulse-width modulated signals for driving the microLEDs at optimal power efficiency and uniformity. The in-pixel circuit receives a sawtooth or triangular pulse from the column driver along with an image signal voltage. It compares the pulse and voltage to generate a current pulse to drive the microLED. This allows accurate grayscale control at low brightness levels using fewer transistors than traditional PWM circuits.

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MicroLED display technology with reduced power consumption by connecting sub-pixels in series. The microLED chip is divided into separate sub-chips by an insulating layer. The second semiconductor layer of each sub-chip is connected to the first semiconductor layer of the next sub-chip via a current diffusion layer. This connects the sub-chips in series, increasing the overall voltage across the microLED chip. This reduces power consumption of the driving TFTs compared to parallel sub-pixels.

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Micro LED display driving circuit that enables high dynamic range by using parallel transistor arrangement for driving micro LEDs. The circuit has two driving transistors, one connected to a high voltage source and the other to a low voltage source, both connected to the micro LED. This parallel configuration allows better contrast and dynamic range compared to driving the micro LED with a single transistor. The micro LEDs themselves are very small, less than 50 microns, to enable high density displays.

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