A peripheral switchable 3D stacked CMOS image sensor

A 1.1 um pitch pixel array fabricated by 45 nm 3D stacked technology, can be switched to peripheral circuits on same wafer or to other stacked wafer for process and signal integrity verification. It supports through silicon connection or direct connection to increase the flexibility by separating pixel array and sensing circuit. The novel wide operation range VCO and low power serializer are implemented to reduce the total power and noise.