This paper proposes a new method to suppress the bias heating effect of the resistive uncooled microbolometer detectors. The bias heating effect especially limits the performance where long integration time and large detector bias voltages are required. The proposed method uses a number of reference detectors for each column of the FPA where the reference detectors have an optimized thermal conductance and are covered by an infrared reflecting material in order to achieve high infrared blindness. The heating and cooling durations of the reference detectors are optimized so that the heating characteristic and the stabilized temperature of the reference detectors are similar to those of the active detectors. Additionally, a resistance mismatch between the reference detectors and the active detectors is introduced in order to match the thermal characteristics and to obtain maximum bias heating cancellation. This intentional mismatch is compensated with a series-connected CMOS resistor to keep the balance in the CTIA circuit. The simulation results show that it is possible to cancel 97.6% of the resistance change due to bias heating with the use of this method, making it possible to increase the gain of the column readout by a factor of about 41.
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