Bengt E. Jonsson
USING FIGURES-OF-MERIT TO EVALUATE MEASURED A/D-CONVERTER PERFORMANCE

This work surveys various figures-of-merit (FOM) that have been used to evaluate and compare measured ADC performance, and takes a first step towards a systematic classification and analysis. Strengths and weaknesses associated with selected figures-of-merit are discussed, and their potential sweet spots or parametric bias is examined using a combination of theoretical analysis and a near-exhaustive set of scientifically reported experimental data. A commonly used FOM is shown to have a distinct, and highly predictable sweet spot with respect to ENOB, and a strong bias towards scaled manufacturing technologies. It is therefore concluded that a continued discussion and treatment of the topic is motivated.

Steven J. Tilden, Solomon M. Max
THE NEW IEEE-STD-1241-2010 FOR ANALOG-TO-DIGITAL CONVERTERS

IEEE Standard 1241-2010 “Terminology and Test Methods for Analog-to-Digital Converters” defines terminology and specifications and describes test methods for measuring the performance of ADC’s. The standard is written for manufacturers and users of ADC’s for use in both static and dynamic applications. The main purpose of this standard is to ensure that manufactures and users of ADC’s have a well-defined set of terms, specifications and test methods so they can understand, describe, and compare the performance of these A/D converters using a common language, with clear definitions. IEEE-Std-1241-2010 was created by the Analog-to-Digital Converter Subcommittee of Technical Committee 10 (TC-10) Waveform Generation, Measurement, and Analysis. TC-10 is part of the IEEE Instrumentation and Measurement Society.

Thomas E. Linnenbrink, William B. Boyer, Travis Ellis, Nicholas G. Paulter, Jr., Steven J. Tilden
IEEE TC-10: UPDATE 2011

There is a world-wide need to standardize terms, test methods, and the computation of performance parameters for devices that generate, measure, and analyze waveforms. Users need to be able to unambiguously specify the device performance required for particular applications. Manufacturers need to be able to unambiguously state the performance of their devices (e.g., instruments, components, etc.). Metrology facilities need to perform calibrations with well-defined methods to produce reliable data expressed in clear terms. Measurement instruments need to acquire data with well-defined methods and present it clearly. Technical Committee 10 (TC-10), the Waveform Generation, Measurement, and Analysis Committee of the IEEE Instrumentation and Measurement (I&M) Society, is tasked to develop standards to address these needs. TC-10 comprises an international group of electronics engineers, mathematicians, professors and physicists with representatives from national metrology laboratories, national science laboratories, component manufacturers, the test instrumentation industry, academia, and end users.

Francesco Centurelli, Pietro Monsurrò, Alessandro Trifiletti
DIGITAL BACKGROUND CALIBRATION OF SUBSAMPLING TIME-INTERLEAVED ADCS

A technique for the digital background calibration of subsampling time-interleaved analog-to-digital converters is proposed. The technique corrects the errors due to gain, offset and timing mismatches among the time-interleaved channels by estimating and nulling the errors with respect to a reference channel through least mean squares loops. Wideband undersampled differentiator filters are exploited thus enabling digital background calibration of timing skews even with wideband input signals outside the first Nyquist band.

Francesco Rizzo, Shyam Somayajula, Domenico Zito, Roberto Saletti, Rolf Becker
AUDIO ADC FOR MOBILE APPLICATIONS FEATURING A NOVEL GAIN CONTROL TECHNIQUE, DITHERING INSERTION AND IDLE TONES SHIFTING

One of the main parts in the audio uplink path for mobile transceivers is an Analog-to-Digital- Converter (ADC) operating in the audio band. The ADC is usually preceded or followed by a Programmable Gain Amplifier (PGA) which allows, together with a digital signal processor, the gain control of the audio transmit path. Changing the gain is an operation which can lead to artifacts as it inserts discontinuities in the audio wave which behave as distortion sources. This paper describes a novel technique for embedding the gain change in the ADC body. In particular, this technique allows a smooth gain change directly in a sigma delta ADC reducing distortions effects and replacing the programmable gain amplifier in the uplink chain, hence allowing performance enhancement and area and power reduction of the overall integrated circuit (IC). In addition, possible implementations of dithering at a minimum area overhead are discussed.