(Georgia Institute of Technology, 2010-11)
Chatterjee, Abhijit; Kook, S.; Gomes, A.; Jin, L.; Wheelright, D.
Linearity testing of high-precision (beyond 20-bit resolution) Analog-to-Digital converters (ADCs) is extremely expensive due to the large number of codes (>16 million for a 24-bit converter) that need to be tested and the associated low data rates making traditional histogram based testing infeasible. Industry often performs linearity test for such high-precision data converters with
significantly reduced numbers of code measurements during production test. Given a specified allowed number of code measurements, the problem is to determine the requisite code points that result in the highest failure coverage. In this report, a methodology and tools for analyzing the “goodness” of a particular choice of test code points versus another is described. A least squares based polynomial fitting approach using measurements made at selected test code points is used to characterize the transfer function of the ADC for INL (Integral Nonlinearity) error. In addition, the characteristics of devices that may escape from the proposed approach (test escapes) are revealed for the specified test via an optimization based search technique. Software simulations are performed to study and validate the proposed methodology.
(Georgia Institute of Technology, 2009-02)
Chatterjee, Abhijit; Gomes, Alfred V.; Choi, Hyun
This paper presents a high-speed periodic signal acquisition technique using incoherent sub-sampling and backend signal reconstruction algorithms. The signal reconstruction algorithms employ a frequency domain analysis for frequency estimation, and suppression of jitter-induced sampling noise. By switching the sampling rate of a digitizer, the analog frequency value of the sampled signal can be recovered. The proposed signal reconstruction uses incoherent sub-sampling to reduce hardware complexity. The results of simulation and hardware experiments indicate that the proposed signal reconstruction algorithms are able to reconstruct multi-tone high-speed periodic signals in the discrete time domain. The new signal acquisition technique simplifies signal acquisition hardware for testing and characterization of high-speed analog and digital signals.