Recently, scientists discovered that relaxor-based ferroelectric single crystals, such as (1-x)Pb(Mg1/3Nb2/3)O3 -xPbTiO3 (PMN-xPT, or PMNT) single crystals, exhibit extra-high pyroelectric responses. They are promising candidates for optical power detectors in broad bandwidth at ultraviolet, visible and infrared wavelength.To fabricate high performance infrared detectors with relaxor-based single crystals, the related readout circuit was investigated to increase signal-to-noise ratio, and 8×1 CMOS readout circuit is fabricated to gain very weak current, which provides a solution for uncooled large focal plane arrays devices based on relaxor-based single crystals.