Title :
Design of a novel low-power 4th-order 1.7 GHz CMOS frequency synthesizer for DCS-1800
Author :
Lehner, Andreas ; Weigel, Robert ; Sewald, Dieter ; Eichfeld, Herbert ; Hajimiri, Ali
Author_Institution :
Inst. of Commun. & Inf. Eng., Linz Univ., Austria
Abstract :
A low-power fully-integrated type-2 4th-order 1.7 GHz CMOS frequency synthesizer for DCS-1800 application is designed and simulated in a 0.25 μm process technology. The frequency switching is achieved using a novel architecture exploiting a direct digital synthesis (DDS) device as the frequency reference. The new topology significantly lowers the undesired sideband power due to divider ratio switching by directly shifting the frequency of the DDS reference. The frequency synthesizer (excluding the DDS device) dissipates only 9 mW of power from a 2 V power supply. It employs a fast-switching novel charge pump circuit and a low-noise fully-integrated differential LC voltage controlled oscillator using on-chip spiral inductors and accumulation-mode capacitors to meet the requirements of a DCS-1800 system. A detailed analysis of the phase noise in the 4th order loop is presented
Keywords :
CMOS integrated circuits; UHF integrated circuits; cellular radio; direct digital synthesis; integrated circuit noise; low-power electronics; mixed analogue-digital integrated circuits; phase noise; 0.25 micron; 1.7 GHz; 2 V; 4th-order loop; 9 mW; CMOS frequency synthesizer; DCS-1800 application; DDS device; DDS frequency reference; accumulation-mode capacitors; differential LC VCO; direct digital synthesis; divider ratio switching; fast-switching charge pump circuit; frequency switching; fully-integrated synthesizer; low-power operation; onchip spiral inductors; phase noise analysis; voltage controlled oscillator; CMOS process; CMOS technology; Charge pumps; Circuit topology; Frequency conversion; Frequency synthesizers; Power supplies; Spirals; System-on-a-chip; Voltage-controlled oscillators;
Conference_Titel :
Circuits and Systems, 2000. Proceedings. ISCAS 2000 Geneva. The 2000 IEEE International Symposium on
Conference_Location :
Geneva
Print_ISBN :
0-7803-5482-6
DOI :
10.1109/ISCAS.2000.857540
