NASA/JPL thermopile detector linear arrays, wire bonded to Black Forest Engineering (BFE) CMOS readout integrated circuits (ROICs), have been utilized in NASA missions such as the Mars Climate Sounder (MCS) and the Diviner Lunar Radiometer Experiment (DLRE). JPL linear array thermopile detectors are fabricated by bulk micro-machining. Micro-machined thermopiles bump bonded to a ROIC are desirable for area (2-D) focal plane arrays (FPAs) because the architecture provides both high detector fill factor and circuit fill factor in the pixel. The proposed innovation is to develop an area array ROIC compatible with bump bondable micro-machined thermopile detectors. The ROIC will be compatible with JPL Bi-Te/Bi-Sb-Te micro-machined thermopile detector arrays to meet requirements of future NASA thermal instruments requiring D-Star > 4 x 109 Jones. Radiation hard-by-design (RHBD) will be utilized with 180 nm CMOS for low 1/f noise readout, operating temp 77-300 K, radiation hardness and noise immunity with on-ROIC ADC. A small pixel pitch and binning is utilized to cover a desired wavelength detection range of 20µm 100 μm. The Phase I ROIC array design will be fabricated on Phase II.