We describe the design of the cryogenic packaging and testing of the Sensor Chip Electronics (SCE) delivered to the Near-Infrared Spectro-Photometer (NISP) instrument for the ESA Euclid mission. The Euclid mission will observe 15 000 deg2 of extragalactic sky1 from the Sun{Earth Lagrange point L2. The payload of the Euclid spacecraft consists of a telescope with 1.2m SiC primary mirror, passively cooled to ~ 125 K, and two focal plane instruments, the visible instrument (VIS) and NISP. At the heart of the NISP instrument is a 4 x 4 mosaic focal plane of Teledyne H2RG infrared detector arrays held at 100K linked using a cryogenic ex cable (CFC) to the SCE at as low as 130 K. The SCE uses the Teledyne SIDECAR Application Specific Integrated Circuit (ASIC) to provide timing, biases, communications, and data conversion for operation of the HAWAII 2 RG (H2RG) Sensor Chip Assembly (SCA) and interfaces to the NISP warm electronics. The SIDECAR ASIC is mounted onto a Silicon Fanout (SiFO) and Invar table support structure and then wirebonded to a printed wiring board assembly (PWB) with passive components and 91-pin nanoconnectors. The PWB is housed within an enclosure which serves as the mechanical and thermal interface to the NISP Support Structure. The qualification and flight SCE were assembled and subjected to environmental testing at the Jet Propulsion Laboratory and then calibrated and tested with the flight lot SCA and CFC at Goddard Space Flight Centers Detector Characterization Lab. The results of the qualification and reliability tests as well as the measured characteristics of the flight SCE will be summarized.
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