A high-resolution analog-to-digital converter (ADC) is needed for a variety
of applications including readout electronics for infrared detectors in fo
cal-plane arrays. The heat load of input/output (I/O) cables between the cr
yogenic environment (4 K) and room temperature dominates the power consumpt
ion of such an ADC. To reduce the number of outputs originating from the ch
ip a 16-bit serial ADC has been developed, Further reduction of the heat lo
ad and more robust signal transmission can be achieved by extracting the se
rial ADC output using an optical fiber coupled to a laser diode. A compact
module (5.75 in x 2.1 in x 1.1 in) has been prototyped to package the ADC c
hip and a laser diode.