A ROIC for diode uncooled IRFPA with non-uniformity compensation technique

A new CMOS readout circuit with non-uniformity calibration for diode uncooled infrared focal plane array (IRFPA) is presented in this paper. A new transconductance amplifier with offset cancellation structure is proposed, utilizing output offset voltage storage. The bias current of each pixel is adjusted by a current splitting DAC array, calibrating the mismatch of the current sources and the non-uniformity of the IRFPA. The proposed circuit prototype with 32 readout channels is fabricated using a 0.35 μm standard CMOS process. The measured results show that the average output offset voltage is decreased by 94% after offset cancellation. The current splitting DAC array shows a DNL/INL less than 2 LSB.