US 6,982,627 B2
Low power regulated amplifier for a transponder
Ralph Oberhuber, Kumhausen/Landshut (Germany); Wolfgang Steinhagen, Mauern (Germany); and Franz Prexl, Niederding (Germany)
Assigned to Texas Instruments Incorporated, Dallas, Tex. (US)
Filed on Jun. 13, 2003, as Appl. No. 10/460,824.
Claims priority of application No. 102 29 459 (DE), filed on Jul. 01, 2002.
Prior Publication US 2004/0135673 A1, Jul. 15, 2004
Int. Cl. H04Q 5/22 (2006.01); H04B 1/16 (2006.01); H03C 1/52 (2006.01)
U.S. Cl. 340—10.1 11 Claims
OG exemplary drawing
 
1. A transponder comprising:
an antenna;
a demodulator;
a signal processing circuit having an output connected to an input of said demodulator and which converts a modulated signal received via said antenna into a processed signal applied at the input of said demodulator and suitable for further processing in said demodulator; and
an amplifier with a predefined amplification factor and a closed loop control circuit serving to maintain the peak-to-peak voltage swing of the processed signal applied at the input of said demodulator substantially constant.