The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 19, 2017
Filed:
Nov. 30, 2016
Analog Devices Global, Hamilton, BM;
Qingdong Meng, Belmont, MA (US);
Hajime Shibata, Toronto, CA;
Richard E. Schreier, New Castle, CA;
Martin Steven McCormick, Cambridge, MA (US);
Yunzhi Dong, Weehawken, NJ (US);
Jose Barreiro Silva, Bedford, MA (US);
Jialin Zhao, Santa Clara, CA (US);
Donald W. Paterson, Winchester, MA (US);
Wenhua W. Yang, Lexington, MA (US);
ANALOG DEVICES GLOBAL, Hamilton, BM;
Abstract
For continuous-time multi-stage noise shaping analog-to-digital converters (CT MASH ADCs), quantization noise cancellation often requires accurate estimation of transfer functions, e.g., a noise transfer function of the front end modulator and a signal transfer function of the back end modulator. To provide quantization noise cancellation, digital quantization noise cancellation filters adaptively tracks transfer function variations due to integrator gain errors, flash-to-DAC timing errors, as well as the inter-stage gain and timing errors. Tracking the transfer functions is performed through the direct cross-correlation between the injected maximum length linear feedback shift registers (LFSR) sequence and modulator outputs and then corrects these non-ideal effects by accurately modeling the transfer functions with programmable finite impulse response (PFIR) filters.