MULTIBAND MULTISTANDARD FREQUENCY SYNTHESIZER FOR MOBILE TV TUNER WITH LC-VCO BY DIGITAL AAC

To improve the phase noise (PN) degradation from the tail current source, this article presents an inductor-capacitor voltage-controlled oscillator (LC-VCO) with digitally controlled programmable low drop out. The digital automatic amplitude calibration (AAC) loop is successively implemented to make the voltage swing constant over 900-1940 MHz. A 40-970 MHz frequency synthesizer with switching dividers is implemented to support the operating frequency range of the multiband mobile TV tuners. The PN of -130 dBc/Hz @ 1 MHz offset is obtained at 474 MHz. The PN variation by the help of AAC loop is measured < 2.4 dB over -40-85 degrees C. (C) 2016 Wiley Periodicals, Inc.