Fully-integrated AMLED micro display system with a hybrid voltage regulator

A fully-integrated active matrix light-emitting diode (AMLED) micro display system is presented. The system consists of a 36×64 pixel-drivers encompassed by a fully on-chip hybrid voltage regulator built on the same silicon chip, then integrated with the AMLED array by using the flip-chip bonding technology. As such, no external passive component is needed. The hybrid voltage regulator consists of a step-up switched-capacitor converter cascaded by a step-down linear regulator. Operating with a wide input range of the lithium-ion battery (2.7V-4.2V), the voltage regulator delivers a maximum power of 216mW with 91% peak efficiency and 78% average efficiency.

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