A camera assembly includes a housing inside of which components are maintained at a cryogenic temperature. The components maintained at cryogenic temperature include a detector that is mounted on an integrated circuit, which in turn is mounted on a platform, such as a ceramic platform, which includes electrical connections for the integrated circuit. The camera assembly also includes one or more subplatforms, maintained above the cryogenic temperature, such as ambient temperature, that receive electrical inputs from outside the housing, and make electrical connections to the platform. The connections may be made from the one or more subplatforms, through openings in the platform and/or outside one or more outer edges of the platform. The assembly may include covers of exposed parts of the one or more subplatforms, to facilitate thermal isolation between the interior of the assembly (at cryogenic temperature) and the one or more subplatforms (above cryogenic temperature).