Oversampled pipeline A/D converters with mismatch shaping

Abstract

This paper presents a pipeline analog-to-digital converter (ADC) with improved linearity. The linearity improvement is achieved through a combination of oversampling and mismatch shaping, which modulates the distortion energy out of band. Mismatch shaping can be realized in a traditional 1-bit/stage pipeline ADC, but the ADC's transfer characteristic properties limit its effectiveness at pushing the distortion out of band. These limitations can be alleviated by using a 1-bit/stage commutative feedback capacitor switching pipeline design. A test chip was fabricated in a 0.35-m CMOS process to demonstrate mismatch shaping. Experimental results obtained indicate that the spurious-free dynamic range improves by 8.5 dB to 76 dB when mismatch shaping is used at an oversampling ratio of 4 and a sampling rate of 61 MHz. The signal-to-noise and distortion ratio improves by 3 dB and the maximum integral nonlinearity decreases from 1.8 to 0.6 LSB at the 12-bit level.

Research on the Application of Intelligent Calibration Device for Nuclear Power Plants Based on Wireless Sensor Technology

“…From the requirements of the test procedures, debugging the source requires the use of numerous bits than its digital multi [17,18]. Using KEITHLEY 2000 (6!-resolution) digital form as a detection device during debugging, the median topic design source is determined to be five and a half.…”

A Segmented Analog Calibration Scheme for Low-Power Multi-Bit Pipeline ADCs

“…Device averaging techniques are ideally suited to over-sampling designs (OSR ≥ 2) with [8] achieving 100 dB SFDR for a 14-bit oversampled pipeline ADC using capacitor averaging techniques. Analog and digital background calibration techniques have also been used in the literature [9]- [12], but tend to consume higher power and area as a result of significant hardware redundancy. Dithering and mismatch-shaping [13] have also been used to design over-sampled pipeline ADCs, but effective bandwidth is reduced as a result of the oversampling, and additional logic is usually required to filter the out-of-band noise.…”

A new capacitor-ratio and offset independent residue amplifier

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