The SIDECAR ASIC: focal plane electronics on a single chip

Abstract

Traditionally, focal plane arrays require extensive external focal plane electronics (FPE) to provide clocks and biases as well as to digitize the analog output signals. The FPE has to be well-designed and is typically large, heavy and powerhungry. Most importantly, the FPE has to be placed some distance away from the FPA, which complicates maintaining low noise performance throughout the complete system. To offer an alternative to the discrete electronics, Rockwell Scientific has developed a new approach known as the SIDECAR application-specific integrated circuit (ASIC). This single chip provides all the functionality necessary to operate an infrared array with the convenience of a pure digital interface to the outside world. This paper will present performance data on the latest generation of the SIDECAR ASIC operating the JWST H2RG detector arrays at cryogenic temperature. The test results demonstrate that an ASIC based FPA system will meet or exceed all performance requirements for the JWST mission. The SIDECAR ASIC has been selected by NASA to become the FPA drive electronics for all shortwave infrared instruments on JWST.

Space qualification and performance results of the SIDECAR ASIC

“…Room temperature and cryogenic measurement results of the SIDECAR ASIC's performance and functionality have been published before (Loose et al [1] and Wong et al [3]). However, these results were obtained in a non-flight configuration using the 337-pin PGA package.…”

“…First prototypes of the new controller concept were available about a year later in form of an application specific integrated circuit (ASIC), named SIDECAR TM for System for Image Digitization, Enhancement, Control And Retrieval. After improving upon a few initial shortfalls, full functionality and excellent performance results of the SIDECAR ASIC have been measured and reported (Loose et al [1]). As a consequence, NASA has decided that all near-infrared instruments of the James Webb Space Telescope (JWST) replace their conventional discrete electronics approach with the SIDECAR ASIC (Rauscher et al [2]).…”

Thermal performance of a radiatively cooled system for quantum optomechanical experiments in space

“…The preprocessing chip, as described for instance in [29], is fixed below the first shield so that its dissipation does not directly affect the optical bench. The harness that connects the detector chip, the preprocessing chip and the spacecraft as Figure 1 schematically shows is assumed to consist of steel.…”

Asymmetry in the noise equivalent angle performance of the JWST fine guidance sensor

“…These detector arrays provide each guider with a wavelength range of 0.6 to 5.0 µm, thus maximizing the available signal from potential guide stars and optimizing the encircled energy for guiding [5]. Like NIRCam and NIRSpec, the FGS also makes use of the SIDECAR ASIC manufactured by Teledyne Imaging Systems for the detector readout [6].…”