An AMLED microdisplay driver SoC with built-in 1.25-Mb/s VLC transmitter

This paper presents the first active matrix LED (AMLED) microdisplay driver with built-in visible light communication (VLC) transmitter. The wide quarter-VGA (WQVGA) display features 400×240 pixels of 30×30 μm
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micro-LEDs (μLED) on a single GaN IC flip-chip bonded to the proposed driver SoC. Pulse-width modulation (PWM) superimposed with on-off keying (OOK) modulation are employed for controlling the display grayscale and modulating the pixels with VLC data simultaneously. Implemented in 0.5-μm CMOS, the SoC enables a microdisplay module featuring 4-bit grayscale at 100-Hz frame rate while achieving 1.25-Mb/s lensless VLC up to 25 cm.