For Full-Text PDF, please login, if you are a member of IEICE,|
or go to Pay Per View on menu list, if you are a nonmember of IEICE.
A 2.4-GHz Temperature-Compensated CMOS LC-VCO for Low Frequency Drift Low-Power Direct-Modulation GFSK Transmitters
IEICE TRANSACTIONS on Electronics
Publication Date: 2005/04/01
Print ISSN: 0916-8516
Type of Manuscript: Special Section PAPER (Special Section on Low-Power LSI and Low-Power IP)
GFSK, CMOS LC-VCO, Bluetooth, direct modulation, low power,
Full Text: PDF>>
A frequency drift of open-loop PLL is an issue for the direct-modulation applications such as Bluetooth transceiver. The drift mainly comes from a temperature variation of VCO during the transmission operation. In this paper, we propose the optimum location of the VCO, considering the temperature gradient through the whole-chip thermal analysis. Moreover, a novel temperature-compensated VCO, employing a new biasing scheme, is proposed. The combination of these two techniques enables the power reduction of the transmitter by 33% without sacrificing the performance.