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A refined selected-codes based test method for pipelined ADC is presented. By selecting a set of specific codes and a self-correction mechanism implementation, the proposed method leverages the redundancy characteristic of the Pipelined ADC to reduce the number of output codes in linearity test after a comprehensive consideration of the comparator offset, capacitance mismatch, gain error, and input noise. Experimental evaluation on a 10-bit 1.5-bit/stage Pipelined ADC as test model has proved that the test data has decreased to 7% compared to the traditional method while maintaining a level of accuracy by minimizing the error of mapping between the comparator and the transition edge. The proposed method efficiently decrease the test cost and heightening the test accuracy.

For the last few decades, micro-channel plates (MCPs), charged coupled devices (CCDs), and hybrid complementary metal-oxide-semiconductor (CMOS) detectors have been the workhorses for collecting photons. More recently, the development of superconducting detectors such as the superconducting tunnel junctions (STJs) and transition edge sensors (TESs) has generated excitement in the imaging community. These detectors provide for simultaneous timing and spectral information as well as relatively good spectral energy resolution. However, STJs and TESs suffer from the major challenge of constructing large format arrays which are required for most imaging applications. Kinetic Inductance Detectors (KIDs) are a relatively new alternative superconducting technology that has many of the same desirable characteristics of STJs and TESs, and offer great promise for creating large-scale formats like current CCDs and CMOS detectors. The current approach for photon detection with KIDs uses a multiple frequency component activation signal. While this method has been proven to enable detection of photons, it has three key drawbacks that limit its utility in remote, size and power constrained applications. The first drawback is that each element of a KID array must be individually characterized under precisely controlled conditions. A second, even greater challenge is that the response of each KID element changes with temperature, necessitating in-system recalibration. Finally, current KIDs require 4-stage cryo-coolers in order to operate at mK temperatures, which are more challenging for space applications. New stimulation and detection approaches for arrays of high-temperature (∼4K) KID sensors are being investigated to simplify the electronics required for the source signal and reduce the impact of even small changes in temperature. Simplification of sensor electronics will enable large and robust arrays of high-temperature KID sensors, opening new photon sensing opportunities in size, mass, and power-constrained applications. This paper describes the current state of SwRI's Internal Research and Development effort to develop a KID detector and associated support hardware.

The influence of random telegraph noise (RTN) in MOSFETs on drain current (Id) during transition edge of pulse gate voltage (Vg) was investigated. The Id fluctuation under dynamic Vg was larger than that under de bias by a factor of 2.2. We have revealed that the initial trap occupation states before varying Vg significantly affect the Id values during the transition edge of dynamic Vg. The trap occupation states were governed by the initial time and the profiles of RTN, e.g., the distribution of time constant (τc and τe). The Id fluctuation under dynamic Vg can be controlled according to the profiles of RTN. These results provide useful information for designing an ultra-high speed circuit.

The features of polarization independence of optical amplifiers achieved by using diffused QW are discussed. Our theoretical results successfully explain why polarization independence can achieve in the long wavelength tail of the modal gain and absorption coefficient but not at photon energies above the transition edge. This explanation applies to other tensile-strained QW for polarization independent applications. The understanding is crucial for optimizing polarization independent devices.

A prototype, cryogenic thermal transfer device has been constructed and tested using a superconducting transition-edge thermal sensor.

Transition edge sensors (TES) based on Ti/Au and Hf/Au bilayers are presented. By varying the relative thickness of the layers, we obtained transition temperatures of between 140-300 mK and 33-105 mK, respectively. Possible applications in the field of X-ray spectroscopy and particle detection are discussed.