Title :
A Δ∑-modulator-less digitally-controlled oscillator using fractional capacitors for GSM/EDGE transmitter
Author :
Nakamura, Takahiro ; Norimatsu, Takayasu ; Uozumi, Toshiya ; Ueda, Keisuke ; Yamawaki, Taizo
Author_Institution :
Central Res. Lab., Hitachi, Ltd., Tokyo, Japan
Abstract :
A ΔΣ-modulator (DSM)-less digitally controlled oscillator (DCO) based on 65-nm CMOS technology, incorporating a fractional-capacitor and ground-shield techniques, for a GSM/EDGE transmitter was developed. The fractional-capacitor and ground-shield techniques, respectively, achieve high frequency resolution (0.6 kHz) without a conventional DSM and small differential non linearity (DNL) of DCO gains (0.12 LSB). A transmitter using the DCO exhibits both low phase error (0.9°) and in-specification receiver-band noise (<;-165 dBc/Hz) thanks to the high frequency resolution and small DNL.
Keywords :
CMOS integrated circuits; capacitors; cellular radio; delta-sigma modulation; oscillators; radio receivers; radio transmitters; ΔΣ-modulator-less digitally-controlled oscillator; CMOS technology; DCO; DSM-less digitally controlled oscillator; GSM/EDGE transmitter; fractional capacitor; frequency 0.6 kHz; frequency resolution; ground-shield technique; low phase error; receiver-band noise; size 65 nm; CMOS integrated circuits; Capacitance; Capacitors; GSM; Noise; Oscillators; Transmitters;
Conference_Titel :
ESSCIRC (ESSCIRC), 2012 Proceedings of the
Conference_Location :
Bordeaux
Print_ISBN :
978-1-4673-2212-6
Electronic_ISBN :
1930-8833
DOI :
10.1109/ESSCIRC.2012.6341342
