| US 7,579,974 B2 | ||
| Digitizer for a digital receiver system | ||
| Mario Chiricosta, Massina (Italy); Philippe Sirito-Olivier, Martigues (France); and Pietro Antonio Paolo Calō, Laterza (Italy) | ||
| Assigned to STMicroelectronics SA, Montrouge (France); and STMicroelectronics S.r.l., Agrate Brianza (MI) (Italy) | ||
| Filed on May 15, 2008, as Appl. No. 12/121,073. | ||
| Claims priority of application No. 07290645 (EP), filed on May 18, 2007. | ||
| Prior Publication US 2008/0284631 A1, Nov. 20, 2008 | ||
| Int. Cl. H03M 1/12 (2006.01) | ||
| U.S. Cl. 341—156 [341/144] | 18 Claims |
| 1. A digitizer for a digital receiver system comprising:
an input terminal to receive a modulated analog input voltage signal;
an output terminal to provide an output voltage signal being a digital conversion of the input voltage signal;
a comparator circuit having an output coupled to said output terminal and comprising at least one operational amplifier having
a first input terminal being coupled to said input terminal; and
a threshold generator circuit between said input terminal and a second input terminal of said at least one operational amplifier,
to provide a tunable voltage reference signal thereto;
wherein said threshold generator circuit comprises a thresholding circuit to determine a threshold voltage value of the modulated
analog input voltage signal, and a tunable voltage reference circuit coupled to the thresholding circuit to generate the tunable
voltage reference signal as a function of the threshold voltage value of the modulated analog input voltage signal.
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