A Split-Based Digital Background Calibration Technique in Pipelined ADCs

Abstract

A digital background calibration technique is proposed to correct gain errors in pipelined analog-to-digital converters (ADCs). The calibration technique performs the error estimation and the adaptive error correction based on the concept of split ADCs. With the 1-or 1.5-bit realization in pipelined stages, capacitor-mismatch errors can be merged with gain errors, and the proposed calibration technique can be utilized. Behavioral simulations show that the signal-to-noise-and-distortion ratio of a 12-bit pipelined ADC with an 8-bit gain accuracy and the capacitor mismatch σ = 0.125% can be improved from 56.4 to 73.8 dB. The calibration process converges in approximately 200 000 cycles.Index Terms-Adaptive systems, analog-to-digital conversion, digital background calibration, pipelined analog-to-digital converters (ADCs).

A statistics-based digital background calibration technique for pipelined ADCs

“…Because of low-power digital signal processing availability in modern CMOS technologies, digital compensation of analog circuit imperfections is becoming popular [9]. In order to correct conversion errors, different digital calibration techniques for pipelined ADCs have been proposed, such as [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17].…”

Calibration Techniques for the Elimination of Non-Monotonic Errors and the Linearity Improvement of A/D Converters

“…In (Wang et al, 2009), a nested digital calibration method is described for a pipeline ADC that does not require an input Sample/Hold Amplifier. A digital background calibration technique is proposed in (Hung & Lee, 2009) to correct gain errors in pipelined ADCs. This calibration technique performs the error estimation and the adaptive error correction based on the concept of split ADCs.…”

A digital processor for full calibration of pipelined ADCs

“…Different calibration techniques have been proposed to improve overall performance of an ADC. Calibration techniques can be of digital nature [2][3][4][5], analog nature [6], or mixed (analog and digital) nature [7]. These techniques are categorized into one of the followings:…”

“…One of advantages of the foreground calibration is possibility of re-calibration. (III) Background calibrations: In some applications, interruption of the ADC to perform calibration is not desirable and hence on-line calibration has been proposed [2,3]. It can track environmental changes such as temperature drifts, component aging and supply voltage fluctuations.…”

“…Therefore in recent years many types of digital calibration schemes have been proposed. Many of these calibration techniques compensate only some specific errors [2][3][4][5] and the need for calibration processor that addresses all errors still remains.…”