## A time-interleaved continuous-time 16 modulator with 20 MHz signal bandwidth (2005)

Venue: | in Proc. ESSCIRC |

Citations: | 1 - 1 self |

### BibTeX

@INPROCEEDINGS{Caldwell05atime-interleaved,

author = {Trevor C. Caldwell and Student Member and David A. Johns},

title = {A time-interleaved continuous-time 16 modulator with 20 MHz signal bandwidth},

booktitle = {in Proc. ESSCIRC},

year = {2005},

pages = {447--450}

}

### OpenURL

### Abstract

Abstract—This paper presents the first implementation results for a time-interleaved continuous-time 16 modulator. The derivation of the time-interleaved continuous-time 16 modulator from a discrete-time 16 modulator is presented. With various simplifications, the resulting modulator has only a single path of integrators, making it robust to DC offsets. A time-interleaved by 2 continuous-time third-order low-pass 16 modulator is designed in a 0.18- m CMOS technology with an oversampling ratio of 5 at sampling frequencies of 100 and 200 MHz. Experimental results show that a signal-to-noise-plus-distortion ratio (SNDR) of 57 dB and a dynamic range of 60 dB are obtained with an input bandwidth of 10 MHz, and an SNDR of 49 dB with a dynamic range of 55 dB is attained with an input bandwidth of 20 MHz. The power consumption is 101 and 103 mW, respectively. Index Terms—Analog-to-digital conversion, continuous-time, delta-sigma modulation, oversampling, time-interleaving.

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